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RJafroc (version 1.0.1)

ExampleCompare3ProperRocFits: Compare three proper-ROC curve fitting models

Description

Applies the Radiological Search Model (RSM) and the Contaminated Binormal Model (CBM) ROC-curve fitting methods to 14 datasets and compares the fits to Proper ROC (PROPROC) fits obtained using Windows software downloaded from the Univ. of Iowa ROC website ca. June 2017.

Usage

ExampleCompare3ProperRocFits(startIndx = 1, endIndx = 14, 
   showPlot = FALSE, saveProprocLrcFile = FALSE, reAnalyze = FALSE)

Arguments

startIndx

An integer in the range 1 to 14.

endIndx

An integer in the range 1 to 14, greater than or equal to startIndx.

showPlot

If TRUE the three plots are shown along with 95 percent confidence intervals on the lowest and uppermost operating points. The default is FALSE.

saveProprocLrcFile

If TRUE the binned datasets are saved for subsequent analysis using other ROC software, e.g., Windows DBM-MRMC. The default is FALSE.

reAnalyze

If TRUE the data is reanalyzed. The default is FALSE in which case the previously saved results are used.

Value

The returned value allResults is a list containing all results from the three parametric model fits. See details.

Details

allResults is a list-array with length equal to (endIndx - startIndx + 1), where each element of the list-array consists of 10 elements, see above. For example, allResults[[1]] corresponds to the dataset corresponding to startIndx. allResults[[2]] corresponds to the dataset corresponding to startIndx+1, etc. A specific member, e.g., allResults[[1]], has the following structure:

  • retRsm The RSM parameters following the output structure of FitRsmRoc

  • retCbm The CBM parameters following the output structure of FitCbmRoc

  • lesDistr The lesion distribution matrix

  • c1 The c-parameter of PROPROC

  • da The d_sub_a parameter of PROPROC

  • aucProp The PROPROC AUC

  • I The number of modalities

  • J The number of readers

  • K1 The number of non-diseased cases

  • K2 The number of diseased cases

The PROPROC parameters were obtained by running Windows software OR DBM-MRMC 2.50 (Sept. 04, 2014, Build 4) with PROPROC and area selected. The RSM and CBM fits are implemented in this package. The corresponding returned objects contain all relevant parameters. Chapter 18 of the author's book has further details. If saveProprocLrcFile is TRUE, the .lrc files will be written to the File-Panes directory, overwriting any existing files with the same names.

## DPC notes on updating the results 2/17/18 ## First run PROPROC on all datasets ## 1. ret14 <- ExampleCompare3ProperRocFits(saveProprocLrcFile = TRUE) ## this generates 14 .lrc files in RJafroc ## 2. Move these files to VmWareShared folder ## 3. Start VmWare and Windows 8 ## 4. Start OR DBM MRMC, select .lrc file, select PROPROC AUC and RUN ALL ## 5. Repeat for each dataset ## 6. Move 2 files (ending with .lroc and PROPROC area pooled.csv) from ## VmWareShared to RJafroc/inst/MRMCRuns to appropriate subdirectories. ## 7. Remove spaces in names of all "proproc area pooled.csv" files ## 8. ret14 <- ExampleCompare3ProperRocFits(reAnalyze = TRUE) ## this generates new results files in RJafroc/inst/ANALYZED/RSM6 ##

References

Chakraborty DP (2017) Observer Performance Methods for Diagnostic Imaging - Foundations, Modeling, and Applications with R-Based Examples, CRC Press, Boca Raton, FL. https://www.crcpress.com/Observer-Performance-Methods-for-Diagnostic-Imaging-Foundations-Modeling/Chakraborty/p/book/9781482214840

Metz CE, Pan X 1999 Proper Binormal ROC Curves: Theory and Maximum-Likelihood Estimation. J Math Psychol. 43,(1):1--33.

Dorfman DD, Berbaum KS, 2000 A contaminated binormal model for ROC data: Part II. A formal model Acad Radiol 7, 427--437.

Examples

Run this code
# NOT RUN {
ExampleCompare3ProperRocFits(1,1)$allResults
# }
# NOT RUN {


# }

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