Recent Releases of SLmetrics

SLmetrics - {SLmetrics} v0.3-4

:bookmark: Version 0.3-4

This update has been focused on two three things:

  1. Optimization of the back-end by using Armadillo instead of Eigen.
  2. Streamlining and extending the documentation
  3. Making functions more flexible

As an example on the increased flexibility is the introduction of the estimator-argument in classification metrics - the new approach enables new additions of aggregation methods as the field evolves. The “old” approach were limited to three values NULL, TRUE and FALSE. Furthermore the function signatures of the generics have been made more flexible - this will enable possible wrapping packages to freely implement argument names off the generic.

:sparkles: Improvements

  • Armadillo backend: All functions have been ported to the C++ Armadillo library, and are heavily templated and Object Oriented. The functions are 5-20x faster than before.
  • Streamlined documentation: All documentation have been reworked, and are now using generic {roxygen2} templates. The new structure of the documentation is focused on shared documentation and therefore equal metrics like recall and sensitivity are aliased, and referenced differently - as a result there should be less noise in the documentation. The creating factor has been removed, and all examples are simplified.
  • Efficient multi-metric evaluation: The Precision-Recall and Receiver Operator Characteristics functions now accepts an indices argument. The indices takes an integer-matrix of corresponding to the sorted probabilities column-wise. See below:

``` r

Classes and

seed

set.seed(1903) classes <- c("Kebab", "Falafel")

Generate actual classes

and response probabilities

actual_classes <- factor( x = sample( x = classes, size = 1e2, replace = TRUE, prob = c(0.7, 0.3) ) )

responseprobabilities <- ifelse( actualclasses == "Kebab", rbeta(sum(actualclasses == "Kebab"), 2, 5), rbeta(sum(actualclasses == "Falafel"), 5, 2) )

Construct response

matrix

probabilitymatrix <- cbind( responseprobabilities, 1 - response_probabilities )

Calculate Precision-Recall

stopifnot( all.equal( target = SLmetrics::pr.curve(actualclasses, probabilitymatrix), current = SLmetrics::pr.curve(actualclasses, probabilitymatrix, indices = SLmetrics::preorder(probability_matrix, TRUE)) ) ) ```

Depending on the system and data, there is a 3x gain in speed. This approach is highly efficient for cases where multiple AUC or curves are to be computed as it avoids sorting the same probability matrix more than once.

:bug:-fixes

  • Relative Root Mean Squared Error: Normalizing the RMSE using the range, the range is always calculated by the distance between max(actual) - min(actual) instead of the weighted distance.

:rocket: New features

  • Hamming Loss: The fraction of the wrong labels to the total number of labels, i.e. , where is the target, is the prediction, and is the “Exclusive, or” operator that returns zero when the target and prediction are identical and one otherwise. The interface to hammingloss() is given below:

``` r set.seed(1903)

classes

classes <- c("Kebab", "Falafel")

actual and

predicted classes

actual <- factor(sample(classes, 10, TRUE)) predicted <- factor(sample(classes, 10, TRUE)) w <- runif(n = 10)

calculate hamming

loss (weighted and unweighted)

SLmetrics::hammingloss( actual, predicted )

> [1] 1

SLmetrics::weighted.hammingloss( actual, predicted, w = w )

> [1] 1

```

  • Tweedie Deviance: The interface to tweedie.deviance() is given below:

``` r

Generate actual

and predicted values

actual_values <- c(1.3, 0.4, 1.2, 1.4, 1.9, 1.0, 1.2)

predicted_values <- c(0.7, 0.5, 1.1, 1.2, 1.8, 1.1, 0.2)

Evaluate performance

SLmetrics::deviance.tweedie( actualvalues, predictedvalues )

> [1] 0.9976545

```

  • Gamma Deviance: The interface to gamma.deviance() is given below:

``` r

Generate actual

and predicted values

actual_values <- c(1.3, 0.4, 1.2, 1.4, 1.9, 1.0, 1.2)

predicted_values <- c(0.7, 0.5, 1.1, 1.2, 1.8, 1.1, 0.2)

Evaluate performance

SLmetrics::deviance.gamma( actualvalues, predictedvalues )

> [1] 0.9976545

```

  • Poisson Deviance: The interface to poisson.deviance() is given below:

``` r

Generate actual

and predicted values

actual_values <- c(1.3, 0.4, 1.2, 1.4, 1.9, 1.0, 1.2)

predicted_values <- c(0.7, 0.5, 1.1, 1.2, 1.8, 1.1, 0.2)

Evaluate performance

SLmetrics::deviance.poisson( actualvalues, predictedvalues )

> [1] 0.3980706

```

  • Mean Arctangent Absolute Error: See here for a general description of the implementation. The metric can be calculated as follows:

``` r

Generate actual

and predicted values

actual_values <- c(1.3, 0.4, 1.2, 1.4, 1.9, 1.0, 1.2)

predicted_values <- c(0.7, 0.5, 1.1, 1.2, 1.8, 1.1, 0.2)

Evaluate performance

SLmetrics::maape( actualvalues, predictedvalues )

> [1] 0.2499164

```

  • Geometric Mean Squared Error: The function have been implemented with logs and antilogs and is robust to zero-valued vectors. The metric can be calculated as follows:

``` r

Generate actual

and predicted values

actual_values <- c(1.3, 0.4, 1.2, 1.4, 1.9, 1.0, 1.2)

predicted_values <- c(0.7, 0.5, 1.1, 1.2, 1.8, 1.1, 0.2)

Evaluate performance

SLmetrics::gmse( actualvalues, predictedvalues )

> [1] 0.03926918

```

:bug: Bug-fixes

:boom: Breaking changes

  • Area under the curve: The new interface is given below:

``` r

Generate x and y

pair

x <- seq(0, pi, length.out = 200) y <- sin(x)

1.1) calculate area

SLmetrics::auc.xy(y = y, x = x)

> [1] 1.999958

```

  • Receiver Operating Characteristics: The new interface is given below:

``` r

define classes

and response probabilities

actual <- factor(c("Class A", "Class B", "Class A")) response <- matrix(cbind( 0.2, 0.8, 0.8, 0.2, 0.7, 0.3 ),nrow = 3, ncol = 2)

receiver operating curve

SLmetrics::roc.curve( actual, response )

> threshold level label fpr tpr

> 1 Inf 1 Class A 0.0 0.0

> 2 0.8 1 Class A 1.0 0.0

> 3 0.8 1 Class A 1.0 0.5

> 4 0.2 1 Class A 1.0 1.0

> 5 -Inf 1 Class A 1.0 1.0

> 6 Inf 2 Class B 0.0 0.0

> 7 0.7 2 Class B 0.0 1.0

> 8 0.3 2 Class B 0.5 1.0

> 9 0.2 2 Class B 1.0 1.0

> 10 -Inf 2 Class B 1.0 1.0

area under the receiver operating

curve

SLmetrics::auc.roc.curve( actual, response, estimator = 0 # 0: class-wise, 1: micro average, 2: macro average )

> Class A Class B

> 0 1

```

  • Precision-Recall Curve: The new interface is given below:

``` r

define classes

and response probabilities

actual <- factor(c("Class A", "Class B", "Class A")) response <- matrix(cbind( 0.2, 0.8, 0.8, 0.2, 0.7, 0.3 ),nrow = 3, ncol = 2)

precision-recall curve

SLmetrics::pr.curve( actual, response )

> threshold level label recall precision

> 1 Inf 1 Class A 0.0 1.000

> 2 0.8 1 Class A 0.0 0.000

> 3 0.8 1 Class A 0.5 0.500

> 4 0.2 1 Class A 1.0 0.667

> 5 -Inf 1 Class A 1.0 0.667

> 6 Inf 2 Class B 0.0 1.000

> 7 0.7 2 Class B 1.0 1.000

> 8 0.3 2 Class B 1.0 0.500

> 9 0.2 2 Class B 1.0 0.333

> 10 -Inf 2 Class B 1.0 0.333

area under the precision-recall

curve

SLmetrics::auc.pr.curve( actual, response, estimator = 0 # 0: class-wise, 1: micro average, 2: macro average )

> Class A Class B

> 0.4166667 1.0000000

```

  • Entropy: entropy() has been renamed to shannon.entropy(). The new interface to shannon.entropy() is given below:

``` r

Observed probabilities

pk <- matrix( cbind(1/2, 1/2), ncol = 2 )

Shannon Entropy

SLmetrics::shannon.entropy(pk)

> [1] 0.6931472

```

The entropy functions have had the base-argument removed, and a new argument has been introduced: normalize. The normalize-parameter averages the calculated entropy across the desired dimensions.

  • Aggregation in classification metrics: The aggregation flag in the classification functions micro have been replaced with the integer-argument estimator which falls back to class-wise evaluation if misspecified. The new interface is given below and is applicable to all functions that has this argument:

``` r set.seed(1903)

classes

classes <- c("Kebab", "Falafel")

actual and

predicted classes

actual <- factor(sample(classes, 10, TRUE)) predicted <- factor(sample(classes, 10, TRUE))

recall: class-wise

SLmetrics::recall( actual, predicted, estimator = 0 )

> Falafel Kebab

> 0 0

recall: micro-averaged

SLmetrics::recall( actual, predicted, estimator = 1 )

> [1] 0

recall: macro-averaged

SLmetrics::recall( actual, predicted, estimator = 1 )

> [1] 0

```

  • Poisson Logloss: The logloss() for count data logloss.integer() were taking a matrix of probabilities. This has been changed to a vector of probabilities.

- C++
Published by serkor1 12 months ago

SLmetrics - {SLmetics} v0.3-3

[!NOTE] Version 0.3-3 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

:rocket: Improvements

  • S3 signatures: All S3-methods now have a generic signature, the functions should now be easier to navigate in argument-wise.

  • Exported Data: Three new datasets have been introduced to the package; the Wine Quality-, Obesity- and Banknote Authentication datasets. Each dataset is comes in named list where features and targets are stored separately. Below is an example from the Obesity dataset:

``` r

1) summarise list

summary(SLmetrics::obesity)

> Length Class Mode

> features 15 data.frame list

> target 2 -none- list

2) head the features

head(SLmetrics::obesity$features)

> caec calc mtrans familyhistorywith_overweight

> 1 sometimes no public_transportation 1

> 2 sometimes sometimes public_transportation 1

> 3 sometimes frequently public_transportation 1

> 4 sometimes frequently walking 0

> 5 sometimes sometimes public_transportation 0

> 6 sometimes sometimes automobile 0

> favc smoke scc male age height fcvc ncp ch2o faf tue

> 1 0 0 0 0 21 1.62 2 3 2 0 1

> 2 0 1 1 0 21 1.52 3 3 3 3 0

> 3 0 0 0 1 23 1.80 2 3 2 2 1

> 4 0 0 0 1 27 1.80 3 3 2 2 0

> 5 0 0 0 1 22 1.78 2 1 2 0 0

> 6 1 0 0 1 29 1.62 2 3 2 0 0

3) head the targets

head(SLmetrics::obesity$target$class)

> [1] NormalWeight NormalWeight Normal_Weight

> [4] OverweightLevelI OverweightLevelII Normal_Weight

> 7 Levels: InsufficientWeight NormalWeight ObesityTypeI ... OverweightLevelII

head(SLmetrics::obesity$target$regression)

> [1] 64.0 56.0 77.0 87.0 89.8 53.0

```

:fire: New features

:rocket: New metrics

  • Poisson LogLoss: The logloss for count data has been implemented. This metric shares the method of logloss and can be used as follows:

``` r

Create factors and response probabilities

actual <- as.integer(factor(c("Class A", "Class B", "Class A"))) weights <- c(0.3,0.9,1) response <- matrix(cbind( 0.2, 0.8, 0.8, 0.2, 0.7, 0.3 ),nrow = 3, ncol = 2)

cat( "Unweighted Poisson Log Loss:", SLmetrics::logloss( actual, response ), "Weighted Poisson Log Loss:", SLmetrics::weighted.logloss( actual = actual, response = response, w = weights ), sep = "\n" )

> Unweighted Poisson Log Loss:

> 1.590672

> Weighted Poisson Log Loss:

> 1.505212

```

  • Area under the Curve: A new set of functions have been introduced which calculates the weighted and unweighted area under the Precision-Recall and Receiver Operator Characteristics curve. See below:

``` r

Create factors and response probabilities

actual <- factor(c("Class A", "Class B", "Class A")) weights <- c(0.3,0.9,1) response <- matrix(cbind( 0.2, 0.8, 0.8, 0.2, 0.7, 0.3 ),nrow = 3, ncol = 2)

calculate area under the

precision-recall curve

SLmetrics::pr.auc( actual = actual, response = response )

> Class A Class B

> 0.4166667 1.0000000

```

:hammer: Metric tools

A new family of Tools-functions are introduced with this update. This addition introduces unexported functions for constructing fast and memory efficient proprietary metrics. These functions are rewritten built-in functions from {stats} and family.

  • Covariance Matrix: A re-written stats::cov.wt(), using Rcpp. Example usage:

``` r

generate values

actual <- c(1.2, 0.3, 0.56, 0.11, 1.01) predicted <- c(0.9, 0.22, 0.76, 0.21, 1.1)

generate covariance matrix

SLmetrics:::cov.wt( cbind( actual, predicted ) )

> $cov

> actual predicted

> actual 0.213330 0.169215

> predicted 0.169215 0.163720

>

> $center

> actual predicted

> 0.636 0.638

>

> $n.obs

> [1] 5

```

  • Area under the curve (AUC): The function calculates the area under the plot for bivariate curves for ordered and unordered x and y pairs. The function assumes that values are ordered and calculates the AUC directly - to control this behaviour use the ordered-argument in the function. Below is an example:

``` r

0) seed

set.seed(1903)

1) Ordered x and y pair

x <- seq(0, pi, length.out = 200) y <- sin(x)

1.1) calculate area

ordered_auc <- SLmetrics::auc(y = y, x = x)

2) Unordered x and y pair

x <- sample(seq(0, pi, length.out = 200)) y <- sin(x)

2.1) calculate area

unordered_auc <- SLmetrics::auc(y = y, x = x)

2.2) calculate area with explicit

ordering

unorderedaucflag <- SLmetrics::auc( y = y, x = x, ordered = FALSE )

3) display result

cat( "AUC (ordered x and y pair)", orderedauc, "AUC (unordered x and y pair)", unorderedauc, "AUC (unordered x and y pair, with unordered flag)", unorderedaucflag, sep = "\n" )

> AUC (ordered x and y pair)

> 1.999958

> AUC (unordered x and y pair)

> -1.720771

> AUC (unordered x and y pair, with unordered flag)

> -1.720771

```

  • Sorting algorithms: A set of sorting and ordering algorithms applicable to matrices have been implemented. The use-case is currently limited to auc.foo, ROC and prROC functions. The algorithms can be used as follows:

``` r

1) generate a 4x4 matrix

with random values to be sorted

set.seed(1903) X <- matrix( data = cbind(sample(16:1)), nrow = 4 )

2) sort matrix

in decreasing order

SLmetrics::presort(X)

> [,1] [,2] [,3] [,4]

> [1,] 3 2 6 1

> [2,] 4 5 10 7

> [3,] 9 8 15 11

> [4,] 13 14 16 12

3) get indices

for sorted matrix

SLmetrics::preorder(X)

> [,1] [,2] [,3] [,4]

> [1,] 1 1 2 4

> [2,] 2 3 3 2

> [3,] 3 2 1 1

> [4,] 4 4 4 3

```

:warning: Breaking changes

  • Logloss: The argument pk has been replaced by response.

- C++
Published by serkor1 about 1 year ago

SLmetrics - {SLmetics} v0.3-2

[!NOTE] Version 0.3-2 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

:rocket: Improvements

  • Regression metrics (See PR https://github.com/serkor1/SLmetrics/pull/64): All regression metrics have had their back-end optimized and are now 2-10 times faster than prior versions.
  • LAPACK/BLAS Support (https://github.com/serkor1/SLmetrics/pull/65): Added LAPACK/BLAS support for efficient matrix-operations.
  • OpenMP: Enabling/disabling OpenMP is now handled on the R-side and obeys suppressMessages(). See below:

``` r

suppress OpenMP messages

suppressMessages( SLmetrics::openmp.off() ) ```

:fire: New features

  • Available threads: The available number of threads can be retrieved using the openmp.threads(). See below:

``` r

number of available

threads

SLmetrics::openmp.threads()

> [1] 24

```

:bug: Bug-fixes

  • Diagnostic Odds Ratio: The dor() is now returning a single <[numeric]>-value instead of k number of identical <[numeric]>-values.

:warning: Breaking Changes

  • OpenMP Interface: The interface to enabling/disabling OpenMP support has been reworked and has a more natural flow. The new interface is described below:

``` r

enable OpenMP

SLmetrics::openmp.on()

> OpenMP enabled!

```

``` r

disable OpenMP

SLmetrics::openmp.off()

> OpenMP disabled!

```

To set the number of threads use the openmp.threads() as follows:

``` r

set number of threads

SLmetrics::openmp.threads(3)

> Using 3 threads.

```

[!NOTE]

Full Changelog: https://github.com/serkor1/SLmetrics/compare/v0.3-1...v0.3-2

- C++
Published by serkor1 over 1 year ago

SLmetrics - {SLmetrics} v0.3-1

[!NOTE]

Version 0.3-1 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

:rocket: Improvements

  • OpenMP Support (PR https://github.com/serkor1/SLmetrics/pull/40): {SLmetrics} now supports parallelization through OpenMP. The OpenMP can be utilized as follows:

``` r

1) probability distribution

generator

rand.sum <- function(n){ x <- sort(runif(n-1)) c(x,1) - c(0,x) }

2) generate probability

matrix

set.seed(1903) pk <- t(replicate(100,rand.sum(1e3)))

3) Enable OpenMP

SLmetrics::setUseOpenMP(TRUE)

> OpenMP usage set to: enabled

system.time(SLmetrics::entropy(pk))

> user system elapsed

> 0.211 0.001 0.010

3) Disable OpenMP

SLmetrics::setUseOpenMP(FALSE)

> OpenMP usage set to: disabled

system.time(SLmetrics::entropy(pk))

> user system elapsed

> 0.001 0.000 0.001

```

  • Entropy with soft labels (https://github.com/serkor1/SLmetrics/issues/37): entropy(), cross.entropy() and relative.entropy() have been introduced. These functions are heavily inspired by {scipy}. The functions can be used as follows:

``` r

1) Define actual

and observed probabilities

1.1) actual probabilies

pk <- matrix( cbind(1/2, 1/2), ncol = 2 )

1.2) observed (estimated) probabilites

qk <- matrix( cbind(9/10, 1/10), ncol = 2 )

2) calculate

Entropy

cat( "Entropy", SLmetrics::entropy( pk ), "Relative Entropy", SLmetrics::relative.entropy( pk, qk ), "Cross Entropy", SLmetrics::cross.entropy( pk, qk ), sep = "\n" )

> Entropy

> 0.6931472

> Relative Entropy

> 0.5108256

> Cross Entropy

> 1.203973

```

:warning: Breaking changes

  • logloss: The argument response have ben renamed to qk as in the entropy()-family to maintain some degree of consistency.
  • entropy.factor(): The function have been deleted and is no more. This was mainly due to avoid the documentation from being too large. The logloss()-function replaces it.

:bug: Bug-fixes

  • Plot-method in ROC and prROC (https://github.com/serkor1/SLmetrics/issues/36): Fixed a bug in plot.ROC() and plot.prROC() where if panels = FALSE additional lines would be added to the plot.

- C++
Published by serkor1 over 1 year ago

SLmetrics - {SLmetrics} v0.3-0

[!NOTE] Version 0.3-0 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

See NEWS or commit history for detailed changes.

:books: What?

:rocket: New features

This update introduces four new features. These are described below,

Cross-Entropy Loss (PR https://github.com/serkor1/SLmetrics/pull/34): Weighted and unweighted cross-entropy loss. The function can be used as follows,

``` r

1) define classes and

observed classes (actual)

classes <- c("Class A", "Class B")

actual <- factor( c("Class A", "Class B", "Class A"), levels = classes

)

2) define probabilites

and construct response_matrix

response <- c( 0.2, 0.8, 0.8, 0.2, 0.7, 0.3 )

response_matrix <- matrix( response, nrow = 3, ncol = 2, byrow = TRUE )

colnames(response_matrix) <- classes

response_matrix

> Class A Class B

> [1,] 0.2 0.8

> [2,] 0.8 0.2

> [3,] 0.7 0.3

3) calculate entropy

SLmetrics::entropy( actual, response_matrix )

> [1] 1.19185

```

Relative Root Mean Squared Error (Commit https://github.com/serkor1/SLmetrics/commit/5521b5b49b1e268c50d6b8d61ae1c6243c4944b3):

The function normalizes the Root Mean Squared Error by a factor. There is no official way of normalizing it - and in {SLmetrics} the RMSE can be normalized using three options; mean-, range- and IQR-normalization. It can be used as follows,

```r

1) define values

actual <- rnorm(1e3) predicted <- actual + rnorm(1e3)

2) calculate Relative Root Mean Squared Error

cat( "Mean Relative Root Mean Squared Error", SLmetrics::rrmse( actual = actual, predicted = predicted, normalization = 0 ), "Range Relative Root Mean Squared Error", SLmetrics::rrmse( actual = actual, predicted = predicted, normalization = 1 ), "IQR Relative Root Mean Squared Error", SLmetrics::rrmse( actual = actual, predicted = predicted, normalization = 2 ), sep = "\n" )

> Mean Relative Root Mean Squared Error

> 2751.381

> Range Relative Root Mean Squared Error

> 0.1564043

> IQR Relative Root Mean Squared Error

> 0.7323898

```

Weighted Receiver Operator Characteristics and Precision-Recall Curves (PR https://github.com/serkor1/SLmetrics/pull/31):

These functions returns the weighted version of TPR, FPR and precision, recalll in weighted.ROC() and weighted.prROC() respectively. The weighted.ROC()-function[^1] can be used as follows,

r actual <- factor(sample(c("Class 1", "Class 2"), size = 1e6, replace = TRUE, prob = c(0.7, 0.3))) response <- ifelse(actual == "Class 1", rbeta(sum(actual == "Class 1"), 2, 5), rbeta(sum(actual == "Class 2"), 5, 2)) w <- ifelse(actual == "Class 1", runif(sum(actual == "Class 1"), 0.5, 1.5), runif(sum(actual == "Class 2"), 1, **2))

``` r

Plot

plot(SLmetrics::weighted.ROC(actual, response, w)) ```

<!-- -->

:warning: Breaking Changes

  • Weighted Confusion Matix: The w-argument in cmatrix() has been removed in favor of the more verbose weighted confusion matrix call weighted.cmatrix()-function. See below,

Prior to version 0.3-0 the weighted confusion matrix were a part of the cmatrix()-function and were called as follows,

r SLmetrics::cmatrix( actual = actual, predicted = predicted, w = weights )

This solution, although simple, were inconsistent with the remaining implementation of weighted metrics in {SLmetrics}. To regain consistency and simplicity the weighted confusion matrix are now retrieved as follows,

``` r

1) define factors

actual <- factor(sample(letters[1:3], 100, replace = TRUE)) predicted <- factor(sample(letters[1:3], 100, replace = TRUE)) weights <- runif(length(actual))

2) without weights

SLmetrics::cmatrix( actual = actual, predicted = predicted ) ```

#>    a  b  c
#> a  7  8 18
#> b  6 13 15
#> c 15 14  4

``` r

2) with weights

SLmetrics::weighted.cmatrix( actual = actual, predicted = predicted, w = weights ) ```

#>          a        b        c
#> a 3.627355 4.443065 7.164199
#> b 3.506631 5.426818 8.358687
#> c 6.615661 6.390454 2.233511

:bug: Bug-fixes

  • Return named vectors: The classification metrics when micro == NULL were not returning named vectors. This has been fixed.

[^1]: The syntax is the same for weighted.prROC()

- C++
Published by serkor1 over 1 year ago

SLmetrics - {SLmetrics} v0.2-0

[!NOTE] Version 0.2-0 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

Improvements

  • documentation: The documentation has gotten some extra love, and now all functions have their formulas embedded, the details section have been freed from a general description of [factor] creation. This will make room for future expansions on the various functions where more details are required.

  • weighted classification metrics: The cmatrix()-function now accepts the argument w which is the sample weights; if passed the respective method will return the weighted metric. Below is an example using sample weights for the confusion matrix,

``` r

1) define factors

actual <- factor(sample(letters[1:3], 100, replace = TRUE)) predicted <- factor(sample(letters[1:3], 100, replace = TRUE)) weights <- runif(length(actual))

2) without weights

SLmetrics::cmatrix( actual = actual, predicted = predicted ) ```

#>    a  b  c
#> a 16  6  8
#> b 14 10 11
#> c  5 15 15

``` r

2) with weights

SLmetrics::cmatrix( actual = actual, predicted = predicted, w = weights ) ```

#>          a        b        c
#> a 8.796270 3.581817 3.422532
#> b 6.471277 4.873632 5.732148
#> c 0.908202 8.319738 8.484611

Calculating weighted metrics manually or by using foo.cmatrix()-method,

``` r

1) weigthed confusion matrix

and weighted accuray

confusion_matrix <- SLmetrics::cmatrix( actual = actual, predicted = predicted, w = weights )

2) pass into accuracy

function

SLmetrics::accuracy( confusion_matrix ) ```

#> [1] 0.4379208

``` r

3) calculate the weighted

accuracy manually

SLmetrics::weighted.accuracy( actual = actual, predicted = predicted, w = weights ) ```

#> [1] 0.4379208

Please note, however, that it is not possible to pass cmatix()-into weighted.accurracy(),

  • Unit-testing: All functions are now being tested for edge-cases in balanced and imbalanced classifcation problems, and regression problems, individually. This will enable a more robust development process and prevent avoidable bugs.

r try( SLmetrics::weighted.accuracy( confusion_matrix ) )

#> Error in UseMethod(generic = "weighted.accuracy", object = ..1) : 
#>   no applicable method for 'weighted.accuracy' applied to an object of class "cmatrix"

Bug-fixes

  • Floating precision: Metrics would give different results based on the method used. This means that foo.cmatrix() and foo.factor() would produce different results (See Issue https://github.com/serkor1/SLmetrics/issues/16). This has been fixed by using higher precision Rcpp::NumericMatrix instead of Rcpp::IntegerMatrix.

  • Miscalculation of Confusion Matrix elements: An error in how FN, TN, FP and TP were calculated have been fixed. No issue has been raised for this bug. This was not something that was caught by the unit-tests, as the total samples were too high to spot this error. It has, however, been fixed now. This means that all metrics that uses these explicitly are now stable, and produces the desired output.

  • Calculation Error in Fowlks Mallows Index: A bug in the calculation of the fmi()-function has been fixed. The fmi()-function now correctly calculates the measure.

  • Calculation Error in Pinball Deviance and Concordance Correlation Coefficient: See issue https://github.com/serkor1/SLmetrics/issues/19. Switched to unbiased variance calculation in ccc()-function. The pinball()-function were missing a weighted quantile function. The issue is now fixed.

  • Calculation Error in Balanced Accuracy: See issue https://github.com/serkor1/SLmetrics/issues/24. The function now correctly adjusts for random chance, and the result matches that of {scikit-learn}

  • Calculation Error in F-beta Score: See issue https://github.com/serkor1/SLmetrics/issues/23. The function werent respecting na.rm and micro, this has been fixed accordingly.

  • Calculation Error in Relative Absolute Error: The function was incorrectly calculating means, instead of sums. This has been fixed.

Breaking changes

  • All regression metrics have had na.rm- and w-arguments removed. All weighted regression metrics have a seperate function on the weighted.foo() to increase consistency across all metrics. See example below,

``` r

1) define regression problem

actual <- rnorm(n = 1e3) predicted <- actual + rnorm(n = 1e3) w <- runif(n = 1e3)

2) unweighted metrics

SLmetrics::rmse(actual, predicted) ```

#> [1] 0.9613081

``` r

3) weighted metrics

SLmetrics::weighted.rmse(actual, predicted, w = w) ```

#> [1] 0.957806
  • The rrmse()-function have been removed in favor of the rrse()-function. This function was incorrectly specified and described in the package.

- C++
Published by serkor1 over 1 year ago

SLmetrics - {SLmetrics} v0.1-1

[!NOTE] Version 0.1-1 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

General

  • Backend changes: All pair-wise metrics arer moved from {Rcpp} to C++, this have reduced execution time by half. All pair-wise metrics are now faster.

Improvements

  • NA-controls: All pair-wise metrics that doesn’t have a micro-argument were handling missing values as according to C++ and {Rcpp} internals. See Issue. Thank you @EmilHvitfeldt for pointing this out. This has now been fixed so functions uses an na.rm-argument to explicitly control for this. See below,

``` r

1) define factors

actual <- factor(c("no", "yes")) predicted <- factor(c(NA, "no"))

2) accuracy with na.rm = TRUE

SLmetrics::accuracy( actual = actual, predicted = predicted, na.rm = TRUE ) ```

#> [1] 0

``` r

2) accuracy with na.rm = FALSE

SLmetrics::accuracy( actual = actual, predicted = predicted, na.rm = FALSE ) ```

#> [1] NaN

Bug-fixes

``` r

1) define actual

classes

actual <- factor( sample(letters[1:2], size = 100, replace = TRUE) )

2) define response

probabilities

response <- runif(100)

3) calculate

ROC and prROC

3.1) ROC

roc <- SLmetrics::ROC( actual, response )

3.2) prROC

prroc <- SLmetrics::prROC( actual, response )

4) plot with panels

FALSE

par(mfrow = c(1,2)) plot( roc, panels = FALSE ) ```

<!-- -->

r plot( prroc, panels = FALSE )

<!-- -->

- C++
Published by serkor1 over 1 year ago

SLmetrics - {SLmetrics} v0.1-0

Version 0.1-0 is considered pre-release of {SLmetrics}. We do not expect any breaking changes, unless a major bug/issue is reported and its nature forces breaking changes.

General

  • {SLmetrics} is a collection of Machine Learning performance evaluation functions for supervised learning. Visit the online documentation on GitHub Pages.

Examples

Supervised classification metrics

``` r

1) actual classes

print( actual <- factor( sample(letters[1:3], size = 10, replace = TRUE) ) ) ```

#>  [1] b a b b a c b c c a
#> Levels: a b c

``` r

2) predicted classes

print( predicted <- factor( sample(letters[1:3], size = 10, replace = TRUE) ) ) ```

#>  [1] c c a b a b c c a c
#> Levels: a b c

``` r

1) calculate confusion

matrix and summarise

it

summary( confusion_matrix <- SLmetrics::cmatrix( actual = actual, predicted = predicted ) ) ```

#> Confusion Matrix (3 x 3) 
#> ================================================================================
#>   a b c
#> a 1 0 2
#> b 1 1 2
#> c 1 1 1
#> ================================================================================
#> Overall Statistics (micro average)
#>  - Accuracy:          0.30
#>  - Balanced Accuracy: 0.31
#>  - Sensitivity:       0.30
#>  - Specificity:       0.65
#>  - Precision:         0.30

``` r

2) calculate false positive

rate using micro average

SLmetrics::fpr( confusion_matrix ) ```

#>         a         b         c 
#> 0.2857143 0.1666667 0.5714286

Supervised regression metrics

``` r

1) actual values

actual <- rnorm(n = 100)

2) predicted values

predicted <- actual + rnorm(n = 100) ```

``` r

1) calculate

huber loss

SLmetrics::huberloss( actual = actual, predicted = predicted ) ```

#> [1] 0.394088

- C++
Published by serkor1 over 1 year ago