mlr_measures_surv.schmid {mlr3proba}R Documentation

Integrated Schmid Score Survival Measure

Description

Calculates the Integrated Schmid Score, aka integrated absolute loss.

For an individual who dies at time t, with predicted Survival function, S, the Schmid Score at time t* is given by

L(S,t|t*) = [(S(t*))I(t ≤ t*, δ = 1)(1/G(t))] + [((1 - S(t*)))I(t > t*)(1/G(t*))]

# nolint where G is the Kaplan-Meier estimate of the censoring distribution.

If integrated == FALSE then the sample mean is taken for the single specified times, t*, and the returned score is given by

L(S,t|t*) = 1/N ∑_i^N L(S_i,t_i|t*)

where N is the number of observations, S_i is the predicted survival function for individual i and t_i is their true survival time.

If integrated == TRUE then an approximation to integration is made by either taking the sample mean over all T unique time-points (method == 1), or by taking a mean weighted by the difference between time-points (method == 2). Then the sample mean is taken over all N observations.

L(S) = 1/(NT) ∑_i^N ∑_j^T L(S_i,t_i|t*_j)

Dictionary

This Measure can be instantiated via the dictionary mlr_measures or with the associated sugar function msr():

MeasureSurvSchmid$new()
mlr_measures$get("surv.schmid")
msr("surv.schmid")

Meta Information

Super classes

mlr3::Measure -> mlr3proba::MeasureSurv -> mlr3proba::MeasureSurvIntegrated -> MeasureSurvSchmid

Active bindings

se

(logical(1))
If TRUE returns the standard error of the measure.

Methods

Public methods

Inherited methods

Method new()

Creates a new instance of this R6 class.

Usage
MeasureSurvSchmid$new(integrated = TRUE, times, method = 2, se = FALSE)
Arguments
integrated

(logical(1))
If TRUE (default), returns the integrated score; otherwise, not integrated.

times

(numeric())
If integrate == TRUE then a vector of time-points over which to integrate the score. If integrate == FALSE then a single time point at which to return the score.

method

(integer(1))
If integrate == TRUE selects the integration weighting method. method == 1 corresponds to weighting each time-point equally and taking the mean score over discrete time-points. method == 2 corresponds to calculating a mean weighted by the difference between time-points. method == 2 is default to be in line with other packages.

se

(logical(1))
If TRUE returns the standard error of the measure.


Method clone()

The objects of this class are cloneable with this method.

Usage
MeasureSurvSchmid$clone(deep = FALSE)
Arguments
deep

Whether to make a deep clone.

References

Schemper, Michael, Henderson, Robin (2000). “Predictive Accuracy and Explained Variation in Cox Regression.” Biometrics, 56, 249–255. doi: 10.1002/sim.1486.

Schmid, Matthias, Hielscher, Thomas, Augustin, Thomas, Gefeller, Olaf (2011). “A Robust Alternative to the Schemper-Henderson Estimator of Prediction Error.” Biometrics, 67(2), 524–535. doi: 10.1111/j.1541-0420.2010.01459.x.

See Also

Other survival measures: mlr_measures_surv.beggC, mlr_measures_surv.calib_alpha, mlr_measures_surv.calib_beta, mlr_measures_surv.chambless_auc, mlr_measures_surv.cindex, mlr_measures_surv.gonenC, mlr_measures_surv.grafSE, mlr_measures_surv.graf, mlr_measures_surv.harrellC, mlr_measures_surv.hung_auc, mlr_measures_surv.intloglossSE, mlr_measures_surv.intlogloss, mlr_measures_surv.logloss_se, mlr_measures_surv.logloss, mlr_measures_surv.maeSE, mlr_measures_surv.mae, mlr_measures_surv.mseSE, mlr_measures_surv.mse, mlr_measures_surv.nagelk_r2, mlr_measures_surv.oquigley_r2, mlr_measures_surv.rmseSE, mlr_measures_surv.rmse, mlr_measures_surv.song_auc, mlr_measures_surv.song_tnr, mlr_measures_surv.song_tpr, mlr_measures_surv.unoC, mlr_measures_surv.uno_auc, mlr_measures_surv.uno_tnr, mlr_measures_surv.uno_tpr, mlr_measures_surv.xu_r2

Other Probabilistic survival measures: mlr_measures_surv.grafSE, mlr_measures_surv.graf, mlr_measures_surv.intloglossSE, mlr_measures_surv.intlogloss, mlr_measures_surv.logloss_se, mlr_measures_surv.logloss

Other distr survival measures: mlr_measures_surv.calib_alpha, mlr_measures_surv.grafSE, mlr_measures_surv.graf, mlr_measures_surv.intloglossSE, mlr_measures_surv.intlogloss, mlr_measures_surv.logloss_se, mlr_measures_surv.logloss


[Package mlr3proba version 0.2.6 Index]