# Data Analysis & Simulation

## Archive for November, 2007

### EasyFit 4.0 Released

Wednesday, November 28th, 2007

The new version of EasyFit introduces a number of features targeted at business users dealing with probability data analysis, modeling, and simulation. For a complete list of new features and fixes in EasyFit 4.0, please click here.

EasyFitXL – EasyFit for Excel

Many businesses use Excel for their data analysis & modeling needs, and even though Excel provides only a basic set of statistical functions, it can be easily extended by installing third party add-ins. An add-in is a piece of software that integrates into Excel and allows you to perform specific tasks which are impossible (or hard, time consuming etc.) to do using Excel alone.

EasyFitXL is a new Excel add-in which ships with EasyFit and allows to use most of the features available in EasyFit right in Excel. With EasyFitXL, you can fit distributions to worksheet data, view distribution graphs, perform probability calculations, and generate random numbers without the need to run EasyFit (the stand-alone application).

The installation process of EasyFitXL is very straightforward: if you have Excel (version 2000 or later) installed on your computer, the EasyFit setup application will automatically install and configure EasyFitXL to properly work with your copy of Excel.

Once EasyFitXL is installed, it can be accessed from the main menu of Excel:

In Excel 2007, it can be found on the Add-Ins page:

Along with the main menu commands, EasyFitXL provides a large number of functions which you can use in Excel worksheets and VBA applications to create advanced models dealing with uncertainty. The worksheet functions are divided into three large categories displayed in the Function Wizard:

The following worksheet and VBA functions are available for more than 40 probability distributions:

• PDF (probability density function)
• CDF (cumulative distribution function)
• inverse CDF (quantile function)
• hazard function (failure rate in reliability analysis)
• distribution mean/variance/standard deviation
• random number generation

These functions can be applied to solve a wide array of problems, ranging from simple probability calculations to Monte Carlo simulation.

### EasyFit: New Version Coming Soon

Monday, November 5th, 2007

A new, fourth version of the distribution fitting application EasyFit is planned to be released later this month (November 2007). We’re currently busy with extensively testing the product and updating the documentation.

The new version will in particular be of great interest to Excel users as, in addition to a stand-alone desktop application, EasyFit will also work as a MS Excel add-in, making it a flexible yet powerful solution for complex probability calculations such as Monte Carlo simulation. Though the desktop application is still a very important part of the product, the advanced Excel integration is something we have got so many requests for.

Some of the new Excel-related features and benefits of EasyFit include:

1) Visual interface for data analysis and simulation: EasyFit integrates into Excel’s main menu, enabling you to easily fit probability distributions to data and generate random numbers without the need to leave the popular spreadsheet application.

2) Worksheet functions: EasyFit makes about 300 new functions available to Excel worksheets, allowing you to perform specific probability calculations and decision making based on the analysis results.

The functions include random number generation, PDF, CDF, Inverse CDF (and more) for all the 40+ probability distributions supported by EasyFit.

3) VBA functions: All the 300 new functions (see above) will also be available to Excel Visual Basic applications, allowing you to use the features of EasyFit in your own VBA programs. You no longer need to remember complex formulas and deal with the lack of support for probability distributions in standard Excel library.

The supported Excel versions are 2000, 2002, 2003, and 2007. The latest version (2007) is worth special mention as, aside from the completely new user interface, it introduces several important features not available in the older versions, specifically the support for larger worksheets and the multi-threaded recalculation. The users of EasyFit will benefit from this new functionality as well – more on this topic next time.

The desktop application (EasyFit) has also been improved: it now provides a new graph type (Q-Q Plot), more flexible graph options, extended export capabilities, P-values calculation, an updated implementation of the Kolmogorov-Smirnov goodness-of-fit test, a new random number generator, and more.

In the meanwhile, if you order the current version of EasyFit this month, you will be able to upgrade to the upcoming new version for free. The free upgrade will also be provided to all the existing customers who purchased EasyFit less than a year ago.

EasyFit: select the best fitting distribution and use it to make better decisions. learn more