Click on the highlighted links to download the appropriate software. I am using Metrowerks CodeWarrior Pro 9 to produce both Macintosh and Windows 95/98/NT programs from the same ANSI C/C++ source code. Each file set is in the form of a zip archive that is automatically unpacked by both Mac OS X and Windows operating systems.

• MLPest: Maximum-Likelihood Parameter Estimation by Sequential Testing
  A package of subroutines and classes written in ANSI C and C++ to implement the maximum-likelihood adaptive staircase method of estimating psychophysical thresholds as described in Harvey (1986, 1997). The package includes all source code and projects for CodeWarrior Pro 9. The source code itself should compile and run on any computer with an ANSI complient C/C++ compiler. Several demonstration programs illustrating the use of the routines and classes are included in the package.
  
  Current version of MLPest: 18 May 2004.
  
  Download MLPest.zip (2.4 MB)

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• PsychoFit: A Macintosh/Windows program that fits s-shaped psychometric functions to psychophysical data using a maximum-likelihood technique. The psychometric functions available are logistic, Weibull, Gaussian integral, cumulative Poisson and step. The program is also included in the above MLPest package. The documentation is pretty weak, and the interface is unix-like. A sample data file is included, so copy its format. I am preparing a users' manual that will provide better documentation. In my "spare time" I am working on a proper, elegant Macintosh version. The current Macintosh files include a carbon version that will run under Mac OS X, as well as on earlier versions of the Mac OS using the CarbonLib. The Windows version of the program should run on Windows 95 and higher.
  
  Current version of PsychoFit: 23 May 2007.
  
  Download PsychoFit_Mac.zip (for Macintosh - 140 KB)
  Download PsychoFit_Win.zip (for Windows --- 322 KB)

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• RscorePlus: A Macintosh/Windows program that fits a multiple-distribution, variable-criterion signal detection theory model to confidence-rating data. The current version will fit Gaussian, Logistiic, Extreme Minimum and Extreme Maximum probability distributions to data along with the (mostly) discredited High Threshold Model for laughs. It was originally derived from Dorfman & Alf's (1969) RSCORE program. The package contains the program, some sample data files, some KaleidaGraph™ template files for graphing, and a documentation file in Adobe pdf format. Double-click on the link below to download the documentation file by itself. You can get the free Adobe Reader, if you need it, from Adobe or use other pdf readers (e.g., Apple's Preview for Mac OS X).
  
  Current version: v 5.5.7, 22 May 2007.
  
  Download RscorePlus_Mac.zip (for Macintosh - 1.9 MB)
  Download RscorePlus_Win.zip (for Windows -- 1.9 MB)
  Download RscorePlus_doc.pdf (Adobe pdf file - 1.6 MB)
  

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• CSF: A Macintosh program that measures a contrast sensitivity function using the MLPest technique. It requires subroutines from Denis Pelli's VideoToolbox and the Pelli video attenuator connected to the monitor. The CSF on my home page was measured with this program, requiring about 23 2AFC trials per spatial frequency.
  Download CSF

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• Sensory Tester: A Macintosh program for measuring taste and smell sensory thresholds (or any thresholds where a limited number of stimuli must be presented manually). The trial-by-trial results and the likelihood functions are displayed graphically.
  Download Sensory Tester