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 Tax Stratification and Estimation Program for Windows (TSEPWin)

Welcome to the TSEPWin page. In addition to two installation packages for TSEPWin, you will find a simulation program (TSEPWinSim) and two utility programs (NullChecker and TwoWay).

History of TSEP and TSEPWin

TSEP was written by Dr. Richard W. Kulp and his nephew, Robert Kulp, in 1988-1989 as a DOS application. This version was in use until the Windows version was developed by Dr. Kulp in 2003. TSEPWin was marketed by Kulp & Associates, LLC, until the summer of 2010 when he retired and closed Kulp & Associates, LLC. In preparation for this closure, he contacted the Multistate Tax Commission with an offer to transfer ownership to MTC and have them provide web hosting with the proviso that TSEPWin be offered to government agencies, businesses and industries free of charge. Dr. Kulp still provides technical support and will update the program as needs arise.

Description of the Programs

TSEPWin assists in designing a statistical audit, drawing the sample and evaluating the resulting audit. The following estimators are available: difference (mean per unit), separate and combined ratio, separate and combined regression and the empirical likelihood confidence interval estimate. The user has considerable flexibility in designing the audit by setting sampling parameters, including choice of stratification method (manual, cumulative square root of frequency, or geometric).

TSEPWin5 is now available in both 32-bit and 64-bit versions. The version you install on a computer depends on the version of Microsoft Office that is installed on the computer, not on the operating system of the computer.  Of course, it is not possible to install the 64-bit version of Office on a 32-bit operating system.  However, it is possible to install either the 32-bit or 64-bit version of Office on a 64-bit computer. TSEPWin5 will not read Access or Excel files and will not write Excel or Word files if the version of TSEPWin5 does not match the version of Microsoft Office.  The proper match is shown in the following table:

Operating System

Version of Office

Use TSEPWin5 Version

Windows 32-Bit

Microsoft Office 32-bit

TSEPWin5 32-bit

 Icon - TSEPWin 
Download - TSEPWin5_X86_setup.exe (36,737 KB)  

Windows 64-bit

Microsoft Office 32-bit

TSEPWin5 32-bit

 Icon - TSEPWin 
Download - TSEPWin5_X86_setup.exe (36,737 KB)  

Windows 64-bit

Microsoft Office 64-bit

TSEPWin5 64-bit

  Icon - TSEPWin 
Download - TSEPWin5_X64_setup.exe (38,862 KB)  


TSEPWinSim is a simulation program for helping users to understand statistical sampling. It requires TSEPWin to run. The population to be simulated is first stratified and the audit designed by TSEPWin. Then TSEPWinSim is run on the output of that design. The TSEPWinSim user then sets the percentage of error in the population for the simulation runs. A separate population is then simulated with that percentage of errors and the true total error is noted. Next, the user sets the number of simulation runs and beginning random number generator seed. TSEPWinSim then repeatedly samples the population and calculates the results for each sample. These are displayed in histograms with summary statistics for the simulation.

  Icon - TSEPWinSim  Download file using icon (604 KB)

TwoWay is a utility that is used only for TSEPWin versions 4.3 and below. It assists in setting up a two-way stratification using results from the designs of several one-way stratifications. This capability is included in TSEPWin5.x. It is included here only for support of audits that were started with older versions of TSEPWin.

 Icon - TwoWay 
Download File (7,385 KB)

NullChecker is a utility for checking fields in Microsoft Access, dBase III and Microsoft Excel files for nulls and non-numeric entries. It does not depend on TSEPWin.

  Icon - NullChecker  Download File (1,130 KB)