Package 'precrec'

Convert a curves and points object to a data frame

Description

The as.data.frame function converts an S3 object generated by evalmod to a data frame.

Usage

## S3 method for class 'sscurves'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'mscurves'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'smcurves'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'mmcurves'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'sspoints'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'mspoints'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'smpoints'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'mmpoints'
as.data.frame(x, row.names = NULL, optional = FALSE, raw_curves = NULL, ...)

## S3 method for class 'aucroc'
as.data.frame(x, row.names = NULL, optional = FALSE, ...)

Arguments

x	An S3 object generated by evalmod. The as.data.frame function takes one of the following S3 objects. ROC and Precision-Recall curves (mode = "rocprc") S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple Basic evaluation measures (mode = "basic") S3 object # of models # of test datasets sspoints single single mspoints multiple single smpoints single multiple mmpoints multiple multiple Fast AUC (ROC) calculation with the U statistic (mode = "aucroc") S3 object # of models # of test datasets aucroc - - See the Value section of evalmod for more details.
row.names	Not used by this method.
optional	Not used by this method.
raw_curves	A Boolean value to specify whether raw curves are shown instead of the average curve. It is effective only when raw_curves is set to TRUE of the evalmod function.
...	Not used by this method.

Value

The as.data.frame function returns a data frame.

See Also

evalmod for generating S3 objects with performance evaluation measures.

Examples

## Not run: 
##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Convert sscurves to a data frame
sscurves.df <- as.data.frame(sscurves)

## Show data frame
head(sscurves.df)

## Generate an sspoints object that contains basic evaluation measures
sspoints <- evalmod(
  mode = "basic", scores = P10N10$scores,
  labels = P10N10$labels
)
## Convert sspoints to a data frame
sspoints.df <- as.data.frame(sspoints)

## Show data frame
head(sspoints.df)


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## Convert mscurves to a data frame
mscurves.df <- as.data.frame(mscurves)

## Show data frame
head(mscurves.df)

## Generate an mspoints object that contains basic evaluation measures
mspoints <- evalmod(mdat, mode = "basic")

## Convert mspoints to a data frame
mspoints.df <- as.data.frame(mspoints)

## Show data frame
head(mspoints.df)


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat, raw_curves = TRUE)

## Convert smcurves to a data frame
smcurves.df <- as.data.frame(smcurves)

## Show data frame
head(smcurves.df)

## Generate an smpoints object that contains basic evaluation measures
smpoints <- evalmod(mdat, mode = "basic")

## Convert smpoints to a data frame
smpoints.df <- as.data.frame(smpoints)

## Show data frame
head(smpoints.df)


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Convert mmcurves to a data frame
mmcurves.df <- as.data.frame(mmcurves)

## Show data frame
head(mmcurves.df)

## Generate an mmpoints object that contains basic evaluation measures
mmpoints <- evalmod(mdat, mode = "basic")

## Convert mmpoints to a data frame
mmpoints.df <- as.data.frame(mmpoints)

## Show data frame
head(mmpoints.df)


##################################################
### N-fold cross validation datasets
###

## Load test data
data(M2N50F5)

## Speficy nessesary columns to create mdat
cvdat <- mmdata(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4,
  modnames = c("m1", "m2"), dsids = 1:5
)

## Generate an mmcurve object that contains ROC and Precision-Recall curves
cvcurves <- evalmod(cvdat)

## Convert mmcurves to a data frame
cvcurves.df <- as.data.frame(cvcurves)

## Show data frame
head(cvcurves.df)

## Generate an mmpoints object that contains basic evaluation measures
cvpoints <- evalmod(cvdat, mode = "basic")

## Convert mmpoints to a data frame
cvpoints.df <- as.data.frame(cvpoints)

## Show data frame
head(cvpoints.df)


##################################################
### AUC with the U statistic
###

## mode = "aucroc"
data(P10N10)
uauc1 <- evalmod(
  scores = P10N10$scores, labels = P10N10$labels,
  mode = "aucroc"
)

# as.data.frame 'aucroc'
as.data.frame(uauc1)

## mode = "aucroc"
samps <- create_sim_samples(10, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)
uauc2 <- evalmod(mdat, mode = "aucroc")

# as.data.frame 'aucroc'
head(as.data.frame(uauc2))

## End(Not run)

---

Retrieve a data frame of AUC scores

Description

The auc function takes an S3 object generated by evalmod and retrieves a data frame with the Area Under the Curve (AUC) scores of ROC and Precision-Recall curves.

Usage

auc(curves)

## S3 method for class 'aucs'
auc(curves)

Arguments

curves

An S3 object generated by evalmod. The auc function accepts the following S3 objects. S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple See the Value section of evalmod for more details.

Value

The auc function returns a data frame with AUC scores.

See Also

evalmod for generating S3 objects with performance evaluation measures. pauc for retrieving a dataset of pAUCs.

Examples

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Shows AUCs
auc(sscurves)


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## Shows AUCs
auc(mscurves)


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat, raw_curves = TRUE)

## Get AUCs
sm_aucs <- auc(smcurves)

## Shows AUCs
sm_aucs

## Get AUCs of Precision-Recall
sm_aucs_prc <- subset(sm_aucs, curvetypes == "PRC")

## Shows AUCs
sm_aucs_prc

##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Get AUCs
mm_aucs <- auc(mmcurves)

## Shows AUCs
mm_aucs

## Get AUCs of Precision-Recall
mm_aucs_prc <- subset(mm_aucs, curvetypes == "PRC")

## Shows AUCs
mm_aucs_prc

---

Calculate CIs of ROC and precision-recall AUCs

Description

The auc_ci function takes an S3 object generated by evalmod and calculates CIs of AUCs when multiple data sets are specified.

Usage

auc_ci(curves, alpha = NULL, dtype = NULL)

## S3 method for class 'aucs'
auc_ci(curves, alpha = 0.05, dtype = "normal")

Arguments

curves	An S3 object generated by evalmod. The auc_ci function accepts the following S3 objects. S3 object # of models # of test datasets smcurves single multiple mmcurves multiple multiple See the Value section of evalmod for more details.
alpha	A numeric value of the significant level (default: 0.05)
dtype	A string to specify the distribution used for CI calculation. dtype distribution normal (default) Normal distribution z Normal distribution t t-distribution

Value

The auc_ci function returns a dataframe of AUC CIs.

See Also

evalmod for generating S3 objects with performance evaluation measures. auc for retrieving a dataset of AUCs.

Examples

##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat)

## Calculate CI of AUCs
sm_auc_cis <- auc_ci(smcurves)

## Shows the result
sm_auc_cis

##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat)

## Calculate CI of AUCs
mm_auc_ci <- auc_ci(mmcurves)

## Shows the result
mm_auc_ci

---

Plot performance evaluation measures with ggplot2

Description

The autoplot function plots performance evaluation measures by using ggplot2 instead of the general R plot.

Usage

## S3 method for class 'sscurves'
autoplot(object, curvetype = c("ROC", "PRC"), ...)

## S3 method for class 'mscurves'
autoplot(object, curvetype = c("ROC", "PRC"), ...)

## S3 method for class 'smcurves'
autoplot(object, curvetype = c("ROC", "PRC"), ...)

## S3 method for class 'mmcurves'
autoplot(object, curvetype = c("ROC", "PRC"), ...)

## S3 method for class 'sspoints'
autoplot(object, curvetype = .get_metric_names("basic"), ...)

## S3 method for class 'mspoints'
autoplot(object, curvetype = .get_metric_names("basic"), ...)

## S3 method for class 'smpoints'
autoplot(object, curvetype = .get_metric_names("basic"), ...)

## S3 method for class 'mmpoints'
autoplot(object, curvetype = .get_metric_names("basic"), ...)

Arguments

object	An S3 object generated by evalmod. The autoplot function accepts the following S3 objects for two different modes, "rocprc" and "basic". ROC and Precision-Recall curves (mode = "rocprc") S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple Basic evaluation measures (mode = "basic") S3 object # of models # of test datasets sspoints single single mspoints multiple single smpoints single multiple mmpoints multiple multiple See the Value section of evalmod for more details.
curvetype	A character vector with the following curve types. ROC and Precision-Recall curves (mode = "rocprc") curvetype description ROC ROC curve PRC Precision-Recall curve Multiple curvetype can be combined, such as c("ROC", "PRC"). Basic evaluation measures (mode = "basic") curvetype description error Normalized ranks vs. error rate accuracy Normalized ranks vs. accuracy specificity Normalized ranks vs. specificity sensitivity Normalized ranks vs. sensitivity precision Normalized ranks vs. precision mcc Normalized ranks vs. Matthews correlation coefficient fscore Normalized ranks vs. F-score Multiple curvetype can be combined, such as c("precision", "sensitivity").
...	Following additional arguments can be specified. type A character to specify the line type as follows. "l" lines "p" points "b" both lines and points show_cb A Boolean value to specify whether point-wise confidence bounds are drawn. It is effective only when calc_avg of the evalmod function is set to TRUE . raw_curves A Boolean value to specify whether raw curves are shown instead of the average curve. It is effective only when raw_curves of the evalmod function is set to TRUE. show_legend A Boolean value to specify whether the legend is shown. ret_grob A logical value to indicate whether autoplot returns a grob object. The grob object is internally generated by arrangeGrob. The grid.draw function takes a grob object and shows a plot. It is effective only when a multiple-panel plot is generated, for example, when curvetype is c("ROC", "PRC"). reduce_points A Boolean value to decide whether the points should be reduced when mode = "rocprc". The points are reduced according to x_bins of the evalmod function. The default values is TRUE.

Value

The autoplot function returns a ggplot object for a single-panel plot and a frame-grob object for a multiple-panel plot.

See Also

evalmod for generating an S3 object. fortify for converting a curves and points object to a data frame. plot for plotting the equivalent curves with the general R plot.

Examples

## Not run: 

## Load libraries
library(ggplot2)
library(grid)

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Plot both ROC and Precision-Recall curves
autoplot(sscurves)

## Reduced/Full supporting points
sampss <- create_sim_samples(1, 50000, 50000)
evalss <- evalmod(scores = sampss$scores, labels = sampss$labels)

# Reduced supporting point
system.time(autoplot(evalss))

# Full supporting points
system.time(autoplot(evalss, reduce_points = FALSE))

## Get a grob object for multiple plots
pp1 <- autoplot(sscurves, ret_grob = TRUE)
plot.new()
grid.draw(pp1)

## A ROC curve
autoplot(sscurves, curvetype = "ROC")

## A Precision-Recall curve
autoplot(sscurves, curvetype = "PRC")

## Generate an sspoints object that contains basic evaluation measures
sspoints <- evalmod(
  mode = "basic", scores = P10N10$scores,
  labels = P10N10$labels
)

## Normalized ranks vs. basic evaluation measures
autoplot(sspoints)

## Normalized ranks vs. precision
autoplot(sspoints, curvetype = "precision")


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## ROC and Precision-Recall curves
autoplot(mscurves)

## Reduced/Full supporting points
sampms <- create_sim_samples(5, 50000, 50000)
evalms <- evalmod(scores = sampms$scores, labels = sampms$labels)

# Reduced supporting point
system.time(autoplot(evalms))

# Full supporting points
system.time(autoplot(evalms, reduce_points = FALSE))

## Hide the legend
autoplot(mscurves, show_legend = FALSE)

## Generate an mspoints object that contains basic evaluation measures
mspoints <- evalmod(mdat, mode = "basic")

## Normalized ranks vs. basic evaluation measures
autoplot(mspoints)

## Hide the legend
autoplot(mspoints, show_legend = FALSE)


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat, raw_curves = TRUE)

## Average ROC and Precision-Recall curves
autoplot(smcurves, raw_curves = FALSE)

## Hide confidence bounds
autoplot(smcurves, raw_curves = FALSE, show_cb = FALSE)

## Raw ROC and Precision-Recall curves
autoplot(smcurves, raw_curves = TRUE, show_cb = FALSE)

## Reduced/Full supporting points
sampsm <- create_sim_samples(4, 5000, 5000)
mdatsm <- mmdata(sampsm$scores, sampsm$labels, expd_first = "dsids")
evalsm <- evalmod(mdatsm, raw_curves = TRUE)

# Reduced supporting point
system.time(autoplot(evalsm, raw_curves = TRUE))

# Full supporting points
system.time(autoplot(evalsm, raw_curves = TRUE, reduce_points = FALSE))

## Generate an smpoints object that contains basic evaluation measures
smpoints <- evalmod(mdat, mode = "basic")

## Normalized ranks vs. average basic evaluation measures
autoplot(smpoints)


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Average ROC and Precision-Recall curves
autoplot(mmcurves, raw_curves = FALSE)

## Show confidence bounds
autoplot(mmcurves, raw_curves = FALSE, show_cb = TRUE)

## Raw ROC and Precision-Recall curves
autoplot(mmcurves, raw_curves = TRUE)

## Reduced/Full supporting points
sampmm <- create_sim_samples(4, 5000, 5000)
mdatmm <- mmdata(sampmm$scores, sampmm$labels,
  modnames = c("m1", "m2"),
  dsids = c(1, 2), expd_first = "modnames"
)
evalmm <- evalmod(mdatmm, raw_curves = TRUE)

# Reduced supporting point
system.time(autoplot(evalmm, raw_curves = TRUE))

# Full supporting points
system.time(autoplot(evalmm, raw_curves = TRUE, reduce_points = FALSE))

## Generate an mmpoints object that contains basic evaluation measures
mmpoints <- evalmod(mdat, mode = "basic")

## Normalized ranks vs. average basic evaluation measures
autoplot(mmpoints)


##################################################
### N-fold cross validation datasets
###

## Load test data
data(M2N50F5)

## Speficy nessesary columns to create mdat
cvdat <- mmdata(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4,
  modnames = c("m1", "m2"), dsids = 1:5
)

## Generate an mmcurve object that contains ROC and Precision-Recall curves
cvcurves <- evalmod(cvdat)

## Average ROC and Precision-Recall curves
autoplot(cvcurves)

## Show confidence bounds
autoplot(cvcurves, show_cb = TRUE)

## Generate an mmpoints object that contains basic evaluation measures
cvpoints <- evalmod(cvdat, mode = "basic")

## Normalized ranks vs. average basic evaluation measures
autoplot(cvpoints)

## End(Not run)

---

Balanced data with 1000 positives and 1000 negatives.

Description

A list contains labels and scores of five different performance levels. All scores were randomly generated.

Usage

data(B1000)

Format

A list with 8 items.

np

number of positives: 1000

nn

number of negatives: 1000

labels

labels of observed data

random_scores

scores of a random performance level

poor_er_scores

scores of a poor early retrieval level

good_er_scores

scores of a good early retrieval level

excel_scores

scores of an excellent level

perf_scores

scores of the perfect level

---

Balanced data with 500 positives and 500 negatives.

Description

A list contains labels and scores of five different performance levels. All scores were randomly generated.

Usage

data(B500)

Format

A list with 8 items.

np

number of positives: 500

nn

number of negatives: 500

labels

labels of observed data

random_scores

scores of a random performance level

poor_er_scores

scores of a poor early retrieval level

good_er_scores

scores of a good early retrieval level

excel_scores

scores of an excellent level

perf_scores

scores of the perfect level

---

Create random samples for simulations

Description

The create_sim_samples function generates random samples with different performance levels.

Usage

create_sim_samples(n_repeat, np, nn, score_names = "random")

Arguments

n_repeat	The number of iterations to make samples.
np	The number of positives in a sample.
nn	The number of negatives in a sample.
score_names	A character vector for the names of the following performance levels. "random" Random "poor_er" Poor early retrieval "good_er" Good early retrieval "excel" Excellent "perf" Perfect "all" All of the above

Value

The create_sim_samples function returns a list with the following items.

• scores: a list of numeric vectors

• labels: an integer vector

• modnames: a character vector of the model names

• dsids: a character vector of the dataset IDs

See Also

mmdata for formatting input data. evalmod for calculation evaluation measures.

Examples

##################################################
### Create a set of samples with 10 positives and 10 negatives
### for the random performance level
###
samps1 <- create_sim_samples(1, 10, 10, "random")

## Show the list structure
str(samps1)


##################################################
### Create two sets of samples with 10 positives and 20 negatives
### for the random and the poor early retrieval performance levels
###
samps2 <- create_sim_samples(2, 10, 20, c("random", "poor_er"))

## Show the list structure
str(samps2)


##################################################
### Create 3 sets of samples with 5 positives and 5 negatives
### for all 5 levels
###
samps3 <- create_sim_samples(3, 5, 5, "all")

## Show the list structure
str(samps3)

---

Evaluate models and calculate performance evaluation measures

Description

The evalmod function calculates ROC and Precision-Recall curves for specified prediction scores and binary labels. It also calculate several basic performance evaluation measures, such as accuracy, error rate, and precision, by specifying mode as "basic".

Usage

evalmod(
  mdat,
  mode = NULL,
  scores = NULL,
  labels = NULL,
  modnames = NULL,
  dsids = NULL,
  posclass = NULL,
  na_worst = TRUE,
  ties_method = "equiv",
  calc_avg = TRUE,
  cb_alpha = 0.05,
  raw_curves = FALSE,
  x_bins = 1000,
  interpolate = TRUE,
  ...
)

Arguments

mdat	An S3 object created by the mmdata function. It contains formatted scores and labels. The evalmod function ignores the following arguments when mdat is specified. scores labels modnames dsids posclass na_worst ties_method These arguments are internally passed to the mmdata function when mdat is unspecified. In that case, both scores and labels must be at least specified.
mode	A string that specifies the types of evaluation measures that the evalmod function calculates. "rocprc" ROC and Precision-Recall curves "prcroc" Same as above "basic" Normalized ranks vs. accuracy, error rate, specificity, sensitivity, precision, Matthews correlation coefficient, and F-score. "aucroc" Fast AUC(ROC) calculation with the U statistic
scores	A numeric dataset of predicted scores. It can be a vector, a matrix, an array, a data frame, or a list. The join_scores function can be useful to make scores with multiple datasets.
labels	A numeric, character, logical, or factor dataset of observed labels. It can be a vector, a matrix, an array, a data frame, or a list. The join_labels function can be useful to make labels with multiple datasets.
modnames	A character vector for the names of the models. The evalmod function automatically generates default names as "m1", "m2", "m3", and so on when it is NULL.
dsids	A numeric vector for test dataset IDs. The evalmod function automatically generates the default ID as 1 when it is NULL.
posclass	A scalar value to specify the label of positives in labels. It must be the same data type as labels. For example, posclass = -1 changes the positive label from 1 to -1 when labels contains 1 and -1. The positive label will be automatically detected when posclass is NULL.
na_worst	A Boolean value for controlling the treatment of NAs in scores. TRUE All NAs are treated as the worst scores FALSE All NAs are treated as the best scores
ties_method	A string for controlling ties in scores. "equiv" Ties are equivalently ranked "first" Ties are ranked in an increasing order as appeared "random" Ties are ranked in random order
calc_avg	A logical value to specify whether average curves should be calculated. It is effective only when dsids contains multiple dataset IDs. For instance, the function calculates the average for the model "m1" when modnames is c("m1", "m1", "m1") and dsids is c(1, 2, 3). The calculation points are defined by x_bins.
cb_alpha	A numeric value with range [0, 1] to specify the alpha value of the point-wise confidence bounds calculation. It is effective only when calc_avg is set to TRUE. For example, it should be 0.05 for the 95% confidence level. The calculation points are defined by x_bins.
raw_curves	A logical value to specify whether all raw curves should be discarded after the average curves are calculated. It is effective only when calc_avg is set to TRUE.
x_bins	An integer value to specify the number of minimum bins on the x-axis. It is then used to define supporting points For instance, the x-values of the supporting points will be c(0, 0.5, 1) and c(0, 0.25, 0.5, 0.75, 1) when x_bins = 2 and x_bins = 4, respectively. All corresponding y-values of the supporting points are calculated. x_bins is effective only when mode is set to rocprc or prcroc.
interpolate	A Boolean value to specify whether or not interpolation of ROC and precision-recall curves are performed. x_bins and calc_avg are ignored and when x_bins is set to FALSE. interpolate is effective only when mode is set to rocprc or prcroc.
...	These additional arguments are passed to mmdata for data preparation.

Value

The evalmod function returns an S3 object that contains performance evaluation measures. The number of models and the number of datasets can be controlled by modnames and dsids. For example, the number of models is "single" and the number of test datasets is "multiple" when modnames = c("m1", "m1", "m1") and dsids = c(1, 2, 3) are specified.

Different S3 objects have different default behaviors of S3 generics, such as plot, autoplot, and fortify.

1. The evalmod function returns one of the following S3 objects when mode is "prcroc". The objects contain ROC and Precision-Recall curves.

   S3 object	# of models	# of test datasets
   sscurves	single	single
   mscurves	multiple	single
   smcurves	single	multiple
   mmcurves	multiple	multiple

2. The evalmod function returns one of the following S3 objects when mode is "basic". They contain five different basic evaluation measures; error rate, accuracy, specificity, sensitivity, and precision.

   S3 object	# of models	# of test datasets
   sspoints	single	single
   mspoints	multiple	single
   smpoints	single	multiple
   mmpoints	multiple	multiple

3. The evalmod function returns the aucroc S3 object when mode is "aucroc", which can be used with 'print' and 'as.data.frame'.

See Also

plot for plotting curves with the general R plot. autoplot and fortify for plotting curves with ggplot2. mmdata for formatting input data. join_scores and join_labels for formatting scores and labels with multiple datasets. format_nfold for creating n-fold cross validation dataset from data frame. create_sim_samples for generating random samples for simulations.

Examples

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)
sscurves

## Generate an sspoints object that contains basic evaluation measures
sspoints <- evalmod(
  mode = "basic", scores = P10N10$scores,
  labels = P10N10$labels
)
sspoints


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)
mscurves

## Generate an mspoints object that contains basic evaluation measures
mspoints <- evalmod(mdat, mode = "basic")
mspoints


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat)
smcurves

## Generate an smpoints object that contains basic evaluation measures
smpoints <- evalmod(mdat, mode = "basic")
smpoints


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mmcurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat)
mmcurves

## Generate an mmpoints object that contains basic evaluation measures
mmpoints <- evalmod(mdat, mode = "basic")
mmpoints


##################################################
### N-fold cross validation datasets
###

## Load test data
data(M2N50F5)

## Speficy nessesary columns to create mdat
cvdat <- mmdata(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4,
  modnames = c("m1", "m2"), dsids = 1:5
)

## Generate an mmcurve object that contains ROC and Precision-Recall curves
cvcurves <- evalmod(cvdat)
cvcurves

## Generate an mmpoints object that contains basic evaluation measures
cvpoints <- evalmod(cvdat, mode = "basic")
cvpoints

## Specify mmdata arguments from evalmod
cvcurves2 <- evalmod(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4,
  modnames = c("m1", "m2"), dsids = 1:5
)
cvcurves2


##################################################
### AUC with the U statistic
###

## mode = "aucroc" returns 'aucroc' S3 object
data(P10N10)

# 'aucroc' S3 object
uauc1 <- evalmod(
  scores = P10N10$scores, labels = P10N10$labels,
  mode = "aucroc"
)

# print 'aucroc'
uauc1

# as.data.frame 'aucroc'
as.data.frame(uauc1)

## It is 2-3 times faster than mode = "rocprc"
# A sample of 100,000
samp1 <- create_sim_samples(1, 50000, 50000)

# a function to test mode = "rocprc"
func_evalmod_rocprc <- function(samp) {
  curves <- evalmod(scores = samp$scores, labels = samp$labels)
  aucs <- auc(curves)
}

# a function to test mode = "aucroc"
func_evalmod_aucroc <- function(samp) {
  uaucs <- evalmod(
    scores = samp$scores, labels = samp$labels,
    mode = "aucroc"
  )
  as.data.frame(uaucs)
}

# Process time
system.time(res1 <- func_evalmod_rocprc(samp1))
system.time(res2 <- func_evalmod_aucroc(samp1))

# AUCs
res1
res2

---

Create n-fold cross validation dataset from data frame

Description

The format_nfold function takes a data frame with scores, label, and n-fold columns and convert it to a list for evalmod and mmdata.

Usage

format_nfold(nfold_df, score_cols, lab_col, fold_col)

Arguments

nfold_df	A data frame that contains at least one score column, label and fold columns.
score_cols	A character/numeric vector that specifies score columns of nfold_df.
lab_col	A number/string that specifies the label column of nfold_df.
fold_col	A number/string that specifies the fold column of nfold_df.

Value

The format_nfold function returns a list that contains multiple scores and labels.

See Also

evalmod for calculation evaluation measures. mmdata for formatting input data. join_scores and join_labels for formatting scores and labels with multiple datasets.

Examples

##################################################
### Convert dataframe with 2 models and 5-fold datasets
###

## Load test data
data(M2N50F5)
head(M2N50F5)

## Convert with format_nfold
nfold_list1 <- format_nfold(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4
)

## Show the list structure
str(nfold_list1)
str(nfold_list1$scores)
str(nfold_list1$labels)


##################################################
### Speficy a single score column
###

## Convert with format_nfold
nfold_list2 <- format_nfold(
  nfold_df = M2N50F5, score_cols = 1,
  lab_col = 3, fold_col = 4
)

## Show the list structure
str(nfold_list2)
str(nfold_list2$scores)
str(nfold_list2$labels)


##################################################
### Use column names
###

## Convert with format_nfold
nfold_list3 <- format_nfold(
  nfold_df = M2N50F5,
  score_cols = c("score1", "score2"),
  lab_col = "label", fold_col = "fold"
)

## Show the list structure
str(nfold_list3)
str(nfold_list3$scores)
str(nfold_list3$labels)

---

Convert a curves and points object to a data frame for ggplot2

Description

The fortify function converts an S3 object generated by evalmod to a data frame for ggplot2.

Usage

## S3 method for class 'sscurves'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'mscurves'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'smcurves'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'mmcurves'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'sspoints'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'mspoints'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'smpoints'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

## S3 method for class 'mmpoints'
fortify(model, data, raw_curves = NULL, reduce_points = FALSE, ...)

Arguments

model	An S3 object generated by evalmod. The fortify function takes one of the following S3 objects. ROC and Precision-Recall curves (mode = "rocprc") S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple Basic evaluation measures (mode = "basic") S3 object # of models # of test datasets sspoints single single mspoints multiple single smpoints single multiple mmpoints multiple multiple See the Value section of evalmod for more details.
data	Not used by this method.
raw_curves	A Boolean value to specify whether raw curves are shown instead of the average curve. It is effective only when raw_curves is set to TRUE of the evalmod function.
reduce_points	A Boolean value to decide whether the points should be reduced. The points are reduced according to x_bins of the evalmod function. The default values is FALSE.
...	Not used by this method.

Value

The fortify function returns a data frame for ggplot2.

See Also

evalmod for generating S3 objects with performance evaluation measures. autoplot for plotting with ggplot2.

Examples

## Not run: 

## Load library
library(ggplot2)

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Let ggplot internally call fortify
p_rocprc <- ggplot(sscurves, aes(x = x, y = y))
p_rocprc <- p_rocprc + geom_line()
p_rocprc <- p_rocprc + facet_wrap(~curvetype)
p_rocprc

## Explicitly fortify sscurves
ssdf <- fortify(sscurves)

## Plot a ROC curve
p_roc <- ggplot(subset(ssdf, curvetype == "ROC"), aes(x = x, y = y))
p_roc <- p_roc + geom_line()
p_roc

## Plot a Precision-Recall curve
p_prc <- ggplot(subset(ssdf, curvetype == "PRC"), aes(x = x, y = y))
p_prc <- p_prc + geom_line()
p_prc

## Generate an sspoints object that contains basic evaluation measures
sspoints <- evalmod(
  mode = "basic", scores = P10N10$scores,
  labels = P10N10$labels
)
## Fortify sspoints
ssdf <- fortify(sspoints)

## Plot normalized ranks vs. precision
p_prec <- ggplot(subset(ssdf, curvetype == "precision"), aes(x = x, y = y))
p_prec <- p_prec + geom_point()
p_prec


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 10 positives and 10 negatives
samps <- create_sim_samples(1, 10, 10, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## Let ggplot internally call fortify
p_rocprc <- ggplot(mscurves, aes(x = x, y = y, color = modname))
p_rocprc <- p_rocprc + geom_line()
p_rocprc <- p_rocprc + facet_wrap(~curvetype)
p_rocprc

## Explicitly fortify mscurves
msdf <- fortify(mscurves)

## Plot ROC curve
df_roc <- subset(msdf, curvetype == "ROC")
p_roc <- ggplot(df_roc, aes(x = x, y = y, color = modname))
p_roc <- p_roc + geom_line()
p_roc

## Fortified data frame can be used for plotting a Precision-Recall curve
df_prc <- subset(msdf, curvetype == "PRC")
p_prc <- ggplot(df_prc, aes(x = x, y = y, color = modname))
p_prc <- p_prc + geom_line()
p_prc

## Generate an mspoints object that contains basic evaluation measures
mspoints <- evalmod(mdat, mode = "basic")

## Fortify mspoints
msdf <- fortify(mspoints)

## Plot normalized ranks vs. precision
df_prec <- subset(msdf, curvetype == "precision")
p_prec <- ggplot(df_prec, aes(x = x, y = y, color = modname))
p_prec <- p_prec + geom_point()
p_prec


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 10 positives and 10 negatives
samps <- create_sim_samples(5, 10, 10, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat, raw_curves = TRUE)

## Let ggplot internally call fortify
p_rocprc <- ggplot(smcurves, aes(x = x, y = y, group = dsid))
p_rocprc <- p_rocprc + geom_smooth(stat = "identity")
p_rocprc <- p_rocprc + facet_wrap(~curvetype)
p_rocprc

## Explicitly fortify smcurves
smdf <- fortify(smcurves, raw_curves = FALSE)

## Plot average ROC curve
df_roc <- subset(smdf, curvetype == "ROC")
p_roc <- ggplot(df_roc, aes(x = x, y = y, ymin = ymin, ymax = ymax))
p_roc <- p_roc + geom_smooth(stat = "identity")
p_roc

## Plot average Precision-Recall curve
df_prc <- subset(smdf, curvetype == "PRC")
p_prc <- ggplot(df_prc, aes(x = x, y = y, ymin = ymin, ymax = ymax))
p_prc <- p_prc + geom_smooth(stat = "identity")
p_prc

## Generate an smpoints object that contains basic evaluation measures
smpoints <- evalmod(mdat, mode = "basic")

## Fortify smpoints
smdf <- fortify(smpoints)

## Plot normalized ranks vs. precision
df_prec <- subset(smdf, curvetype == "precision")
p_prec <- ggplot(df_prec, aes(x = x, y = y, ymin = ymin, ymax = ymax))
p_prec <- p_prec + geom_ribbon(aes(min = ymin, ymax = ymax),
  stat = "identity", alpha = 0.25,
  fill = "grey25"
)
p_prec <- p_prec + geom_point(aes(x = x, y = y))
p_prec


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 10 positives and 10 negatives
samps <- create_sim_samples(5, 10, 10, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Let ggplot internally call fortify
p_rocprc <- ggplot(mmcurves, aes(x = x, y = y, group = dsid))
p_rocprc <- p_rocprc + geom_smooth(aes(color = modname), stat = "identity")
p_rocprc <- p_rocprc + facet_wrap(~curvetype)
p_rocprc

## Explicitly fortify mmcurves
mmdf <- fortify(mmcurves, raw_curves = FALSE)

## Plot average ROC curve
df_roc <- subset(mmdf, curvetype == "ROC")
p_roc <- ggplot(df_roc, aes(x = x, y = y, ymin = ymin, ymax = ymax))
p_roc <- p_roc + geom_smooth(aes(color = modname), stat = "identity")
p_roc

## Plot average Precision-Recall curve
df_prc <- subset(mmdf, curvetype == "PRC")
p_prc <- ggplot(df_prc, aes(x = x, y = y, ymin = ymin, ymax = ymax))
p_prc <- p_prc + geom_smooth(aes(color = modname), stat = "identity")
p_prc

## Generate an mmpoints object that contains basic evaluation measures
mmpoints <- evalmod(mdat, mode = "basic")

## Fortify mmpoints
mmdf <- fortify(mmpoints)

## Plot normalized ranks vs. precision
df_prec <- subset(mmdf, curvetype == "precision")
p_prec <- ggplot(df_prec, aes(x = x, y = y, ymin = ymin, ymax = ymax))
p_prec <- p_prec + geom_ribbon(aes(min = ymin, ymax = ymax, group = modname),
  stat = "identity", alpha = 0.25,
  fill = "grey25"
)
p_prec <- p_prec + geom_point(aes(x = x, y = y, color = modname))
p_prec

## End(Not run)

---

Imbalanced data with 1000 positives and 10000 negatives.

Description

A list contains labels and scores of five different performance levels. All scores were randomly generated.

Usage

data(IB1000)

Format

A list with 8 items.

np

number of positives: 1000

nn

number of negatives: 10000

labels

labels of observed data

random_scores

scores of a random performance level

poor_er_scores

scores of a poor early retrieval level

good_er_scores

scores of a good early retrieval level

excel_scores

scores of an excellent level

perf_scores

scores of the perfect level

---

Imbalanced data with 500 positives and 5000 negatives.

Description

A list contains labels and scores of five different performance levels. All scores were randomly generated.

Usage

data(IB500)

Format

A list with 8 items.

np

number of positives: 500

nn

number of negatives: 5000

labels

labels of observed data

random_scores

scores of a random performance level

poor_er_scores

scores of a poor early retrieval level

good_er_scores

scores of a good early retrieval level

excel_scores

scores of an excellent level

perf_scores

scores of the perfect level

---

Join observed labels of multiple test datasets into a list

Description

join_labels takes observed labels and converts them to a list.

Usage

join_labels(..., byrow = FALSE, chklen = TRUE)

Arguments

...	Multiple datasets. They can be vectors, arrays, matrices, data frames, and lists.
byrow	A Boolean value to specify whether row vectors are used for matrix, data frame, and array.
chklen	A Boolean value to specify whether all list items must be the same lengths.

Value

The join_labels function returns a list that contains all combined label data.

See Also

evalmod for calculation evaluation measures. mmdata for formatting input data. join_scores for formatting scores with multiple datasets.

Examples

##################################################
### Add three numeric vectors
###
l1 <- c(1, 0, 1, 1)
l2 <- c(1, 1, 0, 0)
l3 <- c(0, 1, 0, 1)
labels1 <- join_labels(l1, l2, l3)

## Show the list structure
str(labels1)


##################################################
### Add a matrix and a numeric vector
###
a1 <- matrix(rep(c(1, 0), 4), 4, 2)
labels2 <- join_labels(a1, l3)

## Show the list structure
str(labels2)


##################################################
### Use byrow
###
a2 <- matrix(rep(c(1, 0), 4), 2, 4, byrow = TRUE)
labels3 <- join_labels(a2, l3, byrow = TRUE)

## Show the list structure
str(labels3)


##################################################
### Use chklen
###
l4 <- c(-1, 0, -1)
l5 <- c(0, -1)
labels4 <- join_labels(l4, l5, chklen = FALSE)

## Show the list structure
str(labels4)

---

Join scores of multiple models into a list

Description

The join_scores function takes predicted scores from multiple models and converts them to a list.

Usage

join_scores(..., byrow = FALSE, chklen = TRUE)

Arguments

...	Multiple datasets. They can be vectors, arrays, matrices, data frames, and lists.
byrow	A Boolean value to specify whether row vectors are used for matrix, data frame, and array.
chklen	A Boolean value to specify whether all list items must be the same lengths.

Value

The join_scores function returns a list that contains all combined score data.

See Also

evalmod for calculation evaluation measures. mmdata for formatting input data. join_labels for formatting labels with multiple datasets.

Examples

##################################################
### Add three numeric vectors
###
s1 <- c(1, 2, 3, 4)
s2 <- c(5, 6, 7, 8)
s3 <- c(2, 4, 6, 8)
scores1 <- join_scores(s1, s2, s3)

## Show the list structure
str(scores1)


##################################################
### Add a matrix and a numeric vector
###
a1 <- matrix(seq(8), 4, 2)
scores2 <- join_scores(a1, s3)

## Show the list structure
str(scores2)


##################################################
### Use byrow
###
a2 <- matrix(seq(8), 2, 4, byrow = TRUE)
scores3 <- join_scores(a2, s3, byrow = TRUE)

## Show the list structure
str(scores3)


##################################################
### Use chklen
###
s4 <- c(1, 2, 3)
s5 <- c(5, 6, 7, 8)
scores4 <- join_scores(s4, s5, chklen = FALSE)

## Show the list structure
str(scores4)

---

5-fold cross validation sample.

Description

A data frame contains labels and scores for 5-fold test sets.

Usage

data(M2N50F5)

Format

A data frame with 4 columns.

score1

50 random scores

score2

50 random scores

label

50 labels as 'pos' or 'neg'

fold

50 fold IDs as 1:5

---

Reformat input data for performance evaluation calculation

Description

The mmdata function takes predicted scores and labels and returns an mdat object. The evalmod function takes an mdat object as input data to calculate evaluation measures.

Usage

mmdata(
  scores,
  labels,
  modnames = NULL,
  dsids = NULL,
  posclass = NULL,
  na_worst = TRUE,
  ties_method = "equiv",
  expd_first = NULL,
  mode = "rocprc",
  nfold_df = NULL,
  score_cols = NULL,
  lab_col = NULL,
  fold_col = NULL,
  ...
)

Arguments

scores	A numeric dataset of predicted scores. It can be a vector, a matrix, an array, a data frame, or a list. The join_scores function can be useful to make scores with multiple datasets.
labels	A numeric, character, logical, or factor dataset of observed labels. It can be a vector, a matrix, an array, a data frame, or a list. The join_labels function can be useful to make labels with multiple datasets.
modnames	A character vector for the names of the models. The evalmod function automatically generates default names as "m1", "m2", "m3", and so on when it is NULL.
dsids	A numeric vector for test dataset IDs. The evalmod function automatically generates the default ID as 1 when it is NULL.
posclass	A scalar value to specify the label of positives in labels. It must be the same data type as labels. For example, posclass = -1 changes the positive label from 1 to -1 when labels contains 1 and -1. The positive label will be automatically detected when posclass is NULL.
na_worst	A Boolean value for controlling the treatment of NAs in scores. TRUE All NAs are treated as the worst scores FALSE All NAs are treated as the best scores
ties_method	A string for controlling ties in scores. "equiv" Ties are equivalently ranked "first" Ties are ranked in an increasing order as appeared "random" Ties are ranked in random order
expd_first	A string to indicate which of the two variables - model names or test dataset IDs should be expanded first when they are automatically generated. "modnames" Model names are expanded first. For example, The mmdata function generates modnames as c("m1", "m2") and dsids as c(1, 1) when two vectors are passed as input, and modnames and dsids are unspecified. "dsids" Test dataset IDs are expanded first. For example, The mmdata function generates modnames as c("m1", "m1") and dsids as c(1, 2) when two vectors are passed as input, and modnames and dsids are unspecified.
mode	A string that specifies the types of evaluation measures that the evalmod function calculates. "rocprc" ROC and Precision-Recall curves "prcroc" Same as above "basic" Normalized ranks vs. accuracy, error rate, specificity, sensitivity, precision, Matthews correlation coefficient, and F-score. "aucroc" Fast AUC(ROC) calculation with the U statistic
nfold_df	A data frame that contains at least one score column, label and fold columns.
score_cols	A character/numeric vector that specifies score columns of nfold_df.
lab_col	A number/string that specifies the label column of nfold_df.
fold_col	A number/string that specifies the fold column of nfold_df.
...	Not used by this method.

Value

The mmdata function returns an mdat object that contains formatted labels and score ranks. The object can be used as input data for the evalmod function.

See Also

evalmod for calculation evaluation measures. join_scores and join_labels for formatting scores and labels with multiple datasets. format_nfold for creating n-fold cross validation dataset from data frame.

Examples

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate mdat object
ssmdat1 <- mmdata(P10N10$scores, P10N10$labels)
ssmdat1
ssmdat2 <- mmdata(1:8, sample(c(0, 1), 8, replace = TRUE))
ssmdat2


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")

## Multiple models & single test dataset
msmdat1 <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)
msmdat1

## Use join_scores and join_labels
s1 <- c(1, 2, 3, 4)
s2 <- c(5, 6, 7, 8)
scores <- join_scores(s1, s2)

l1 <- c(1, 0, 1, 1)
l2 <- c(1, 0, 1, 1)
labels <- join_labels(l1, l2)

msmdat2 <- mmdata(scores, labels, modnames = c("ms1", "ms2"))
msmdat2


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "good_er")

## Single model & multiple test datasets
smmdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)
smmdat


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "all")

## Multiple models & multiple test datasets
mmmdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)
mmmdat


##################################################
### N-fold cross validation datasets
###

## Load test data
data(M2N50F5)
head(M2N50F5)

## Speficy nessesary columns to create mdat
cvdat1 <- mmdata(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4,
  modnames = c("m1", "m2"), dsids = 1:5
)
cvdat1

## Use column names
cvdat2 <- mmdata(
  nfold_df = M2N50F5, score_cols = c("score1", "score2"),
  lab_col = "label", fold_col = "fold",
  modnames = c("m1", "m2"), dsids = 1:5
)
cvdat2

---

A small example dataset with several tied scores.

Description

A list contains labels and scores for 10 positives and 10 negatives.

Usage

data(P10N10)

Format

A list with 4 items.

np

number of positives: 10

nn

number of negatives: 10

labels

20 labels of observed data

scores

20 scores with some ties

---

Calculate partial AUCs

Description

The part function takes an S3 object generated by evalmod and calculate partial AUCs and Standardized partial AUCs of ROC and Precision-Recall curves. Standardized pAUCs are standardized to the range between 0 and 1.

Usage

part(curves, xlim = NULL, ylim = NULL, curvetype = NULL)

## S3 method for class 'sscurves'
part(curves, xlim = c(0, 1), ylim = c(0, 1), curvetype = c("ROC", "PRC"))

## S3 method for class 'mscurves'
part(curves, xlim = c(0, 1), ylim = c(0, 1), curvetype = c("ROC", "PRC"))

## S3 method for class 'smcurves'
part(curves, xlim = c(0, 1), ylim = c(0, 1), curvetype = c("ROC", "PRC"))

## S3 method for class 'mmcurves'
part(curves, xlim = c(0, 1), ylim = c(0, 1), curvetype = c("ROC", "PRC"))

Arguments

curves	An S3 object generated by evalmod. The part function accepts the following S3 objects. S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple See the Value section of evalmod for more details.
xlim	A numeric vector of length two to specify x range between two points in [0, 1]
ylim	A numeric vector of length two to specify y range between two points in [0, 1]
curvetype	A character vector with the following curve types. curvetype description ROC ROC curve PRC Precision-Recall curve Multiple curvetype can be combined, such as c("ROC", "PRC").

Value

The part function returns the same S3 object specified as input with calculated pAUCs and standardized pAUCs.

See Also

evalmod for generating S3 objects with performance evaluation measures. pauc for retrieving a dataset of pAUCs.

Examples

## Not run: 

## Load library
library(ggplot2)

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Calculate partial AUCs
sscurves.part <- part(sscurves, xlim = c(0.25, 0.75))

## Show AUCs
sscurves.part

## Plot partial curve
plot(sscurves.part)

## Plot partial curve with ggplot
autoplot(sscurves.part)


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## Calculate partial AUCs
mscurves.part <- part(mscurves, xlim = c(0, 0.75), ylim = c(0.25, 0.75))

## Show AUCs
mscurves.part

## Plot partial curves
plot(mscurves.part)

## Plot partial curves with ggplot
autoplot(mscurves.part)


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat)

## Calculate partial AUCs
smcurves.part <- part(smcurves, xlim = c(0.25, 0.75))

## Show AUCs
smcurves.part

## Plot partial curve
plot(smcurves.part)

## Plot partial curve with ggplot
autoplot(smcurves.part)


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Calculate partial AUCs
mmcurves.part <- part(mmcurves, xlim = c(0, 0.25))

## Show AUCs
mmcurves.part

## Plot partial curves
plot(mmcurves.part)

## Plot partial curves with ggplot
autoplot(mmcurves.part)

## End(Not run)

---

Retrieve a data frame of pAUC scores

Description

The auc function takes an S3 object generated by part and evalmod and retrieves a data frame with the partial AUC scores of ROC and Precision-Recall curves.

Usage

pauc(curves)

## S3 method for class 'aucs'
pauc(curves)

Arguments

curves

An S3 object generated by part and evalmod. The pauc function accepts the following S3 objects. S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple See the Value section of evalmod for more details.

Value

The auc function returns a data frame with pAUC scores.

See Also

evalmod for generating S3 objects with performance evaluation measures. part for calculation of pAUCs. auc for retrieving a dataset of AUCs.

Examples

##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Calculate partial AUCs
sscurves.part <- part(sscurves, xlim = c(0.25, 0.75))

## Shows pAUCs
pauc(sscurves.part)

##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## Calculate partial AUCs
mscurves.part <- part(mscurves, xlim = c(0, 0.75), ylim = c(0.25, 0.75))

## Shows pAUCs
pauc(mscurves.part)

##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat, raw_curves = TRUE)

## Calculate partial AUCs
smcurves.part <- part(smcurves, xlim = c(0.25, 0.75))

## Shows pAUCs
pauc(smcurves.part)

##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(4, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Calculate partial AUCs
mmcurves.part <- part(mmcurves, xlim = c(0, 0.25))

## Shows pAUCs
pauc(mmcurves.part)

---

Plot performance evaluation measures

Description

The plot function creates a plot of performance evaluation measures.

Usage

## S3 method for class 'sscurves'
plot(x, y = NULL, ...)

## S3 method for class 'mscurves'
plot(x, y = NULL, ...)

## S3 method for class 'smcurves'
plot(x, y = NULL, ...)

## S3 method for class 'mmcurves'
plot(x, y = NULL, ...)

## S3 method for class 'sspoints'
plot(x, y = NULL, ...)

## S3 method for class 'mspoints'
plot(x, y = NULL, ...)

## S3 method for class 'smpoints'
plot(x, y = NULL, ...)

## S3 method for class 'mmpoints'
plot(x, y = NULL, ...)

Arguments

x	An S3 object generated by evalmod. The plot function accepts the following S3 objects. ROC and Precision-Recall curves (mode = "rocprc") S3 object # of models # of test datasets sscurves single single mscurves multiple single smcurves single multiple mmcurves multiple multiple Basic evaluation measures (mode = "basic") S3 object # of models # of test datasets sspoints single single mspoints multiple single smpoints single multiple mmpoints multiple multiple See the Value section of evalmod for more details.
y	Equivalent with curvetype.
...	All the following arguments can be specified. curvetype ROC and Precision-Recall curves (mode = "rocprc") curvetype description ROC ROC curve PRC Precision-Recall curve Multiple curvetype can be combined, such as c("ROC", "PRC"). Basic evaluation measures (mode = "basic") curvetype description error Normalized ranks vs. error rate accuracy Normalized ranks vs. accuracy specificity Normalized ranks vs. specificity sensitivity Normalized ranks vs. sensitivity precision Normalized ranks vs. precision mcc Normalized ranks vs. Matthews correlation coefficient fscore Normalized ranks vs. F-score Multiple curvetype can be combined, such as c("precision", "sensitivity"). type A character to specify the line type as follows. "l" lines "p" points "b" both lines and points show_cb A Boolean value to specify whether point-wise confidence bounds are drawn. It is effective only when calc_avg of the evalmod function is set to TRUE. raw_curves A Boolean value to specify whether raw curves are shown instead of the average curve. It is effective only when raw_curves of the evalmod function is set to TRUE. show_legend A Boolean value to specify whether the legend is shown.

Value

The plot function shows a plot and returns NULL.

See Also

evalmod for generating an S3 object. autoplot for plotting the equivalent curves with ggplot2.

Examples

## Not run: 
##################################################
### Single model & single test dataset
###

## Load a dataset with 10 positives and 10 negatives
data(P10N10)

## Generate an sscurve object that contains ROC and Precision-Recall curves
sscurves <- evalmod(scores = P10N10$scores, labels = P10N10$labels)

## Plot both ROC and Precision-Recall curves
plot(sscurves)

## Plot a ROC curve
plot(sscurves, curvetype = "ROC")

## Plot a Precision-Recall curve
plot(sscurves, curvetype = "PRC")

## Generate an sspoints object that contains basic evaluation measures
sspoints <- evalmod(
  mode = "basic", scores = P10N10$scores,
  labels = P10N10$labels
)

## Plot normalized ranks vs. basic evaluation measures
plot(sspoints)

## Plot normalized ranks vs. precision
plot(sspoints, curvetype = "precision")


##################################################
### Multiple models & single test dataset
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(1, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mscurves <- evalmod(mdat)

## Plot both ROC and Precision-Recall curves
plot(mscurves)

## Hide the legend
plot(mscurves, show_legend = FALSE)

## Generate an mspoints object that contains basic evaluation measures
mspoints <- evalmod(mdat, mode = "basic")

## Plot normalized ranks vs. basic evaluation measures
plot(mspoints)

## Hide the legend
plot(mspoints, show_legend = FALSE)


##################################################
### Single model & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "good_er")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an smcurve object that contains ROC and Precision-Recall curves
smcurves <- evalmod(mdat, raw_curves = TRUE)

## Plot average ROC and Precision-Recall curves
plot(smcurves, raw_curves = FALSE)

## Hide confidence bounds
plot(smcurves, raw_curves = FALSE, show_cb = FALSE)

## Plot raw ROC and Precision-Recall curves
plot(smcurves, raw_curves = TRUE, show_cb = FALSE)

## Generate an smpoints object that contains basic evaluation measures
smpoints <- evalmod(mdat, mode = "basic")

## Plot normalized ranks vs. average basic evaluation measures
plot(smpoints)


##################################################
### Multiple models & multiple test datasets
###

## Create sample datasets with 100 positives and 100 negatives
samps <- create_sim_samples(10, 100, 100, "all")
mdat <- mmdata(samps[["scores"]], samps[["labels"]],
  modnames = samps[["modnames"]],
  dsids = samps[["dsids"]]
)

## Generate an mscurve object that contains ROC and Precision-Recall curves
mmcurves <- evalmod(mdat, raw_curves = TRUE)

## Plot average ROC and Precision-Recall curves
plot(mmcurves, raw_curves = FALSE)

## Show confidence bounds
plot(mmcurves, raw_curves = FALSE, show_cb = TRUE)

## Plot raw ROC and Precision-Recall curves
plot(mmcurves, raw_curves = TRUE)

## Generate an mmpoints object that contains basic evaluation measures
mmpoints <- evalmod(mdat, mode = "basic")

## Plot normalized ranks vs. average basic evaluation measures
plot(mmpoints)


##################################################
### N-fold cross validation datasets
###

## Load test data
data(M2N50F5)

## Speficy nessesary columns to create mdat
cvdat <- mmdata(
  nfold_df = M2N50F5, score_cols = c(1, 2),
  lab_col = 3, fold_col = 4,
  modnames = c("m1", "m2"), dsids = 1:5
)

## Generate an mmcurve object that contains ROC and Precision-Recall curves
cvcurves <- evalmod(cvdat)

## Average ROC and Precision-Recall curves
plot(cvcurves)

## Show confidence bounds
plot(cvcurves, show_cb = TRUE)

## Generate an mmpoints object that contains basic evaluation measures
cvpoints <- evalmod(cvdat, mode = "basic")

## Normalized ranks vs. average basic evaluation measures
plot(cvpoints)

## End(Not run)

---

precrec: A package for computing accurate ROC and Precision-Recall curves

Description

The precrec package contains several functions and S3 generics to provide a robust platform for performance evaluation of binary classifiers.

Functions

The precrec package provides the following six functions.

Function	Description
evalmod	Main function to calculate evaluation measures
mmdata	Reformat input data for performance evaluation calculation
join_scores	Join scores of multiple models into a list
join_labels	Join observed labels of multiple test datasets into a list
create_sim_samples	Create random samples for simulations
format_nfold	Create n-fold cross validation dataset from data frame

S3 generics

The precrec package provides nine different S3 generics for the S3 objects generated by the evalmod function.

S3 generic	Library	Description
print	base	Print the calculation results and the summary of the test data
as.data.frame	base	Convert a precrec object to a data frame
plot	graphics	Plot performance evaluation measures
autoplot	ggplot2	Plot performance evaluation measures with ggplot2
fortify	ggplot2	Prepare a data frame for ggplot2
auc	precrec	Make a data frame with AUC scores
part	precrec	Calculate partial curves and partial AUC scores
pauc	precrec	Make a data frame with pAUC scores
auc_ci	precrec	Calculate confidence intervals of AUC scores

Performance measure calculations

The evalmod function calculates ROC and Precision-Recall curves and returns an S3 object. The generated S3 object can be used with several different S3 generics, such as print and plot. The evalmod function can also calculate basic evaluation measures - error rate, accuracy, specificity, sensitivity, precision, Matthews correlation coefficient, and F-Score.

Data preparation

The mmdata function creates an input dataset for the evalmod function. The generated dataset contains formatted scores and labels.

join_scores and join_labels are helper functions to combine multiple scores and labels.

The create_sim_samples function creates test datasets with five different performance levels.

Data visualization

plot takes an S3 object generated by evalmod as input and plot corresponding curves.

autoplot uses ggplot to plot curves.

Result retrieval

as.data.frame takes an S3 object generated by evalmod as input and and returns a data frame with calculated curve points.

auc and pauc returns a data frame with AUC scores and partial AUC scores, respectively. auc_ci returns confidence intervals of AUCs for both ROC and precision-recall curves.

---