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DecisionT oolworks

Decision Tree, Sensitivity Analysis, and

Monte Carlo Simulation Add-Ins for Excel

My products are decision analysis tools. My first decision analysis software was developed in 1973 on the HP 2000 minicomputer with teletype terminals and BASIC. In the early 1980s, I wrote decision analysis software on an Apple II using Applesoft Basic. Soon thereafter I used Turbo Pascal on the original IBM PC. In the early 1990s the Excel spreadsheet became my preferred programming environment. One of my products is still mostly Excel 4 macro programming language code from 1992.

From 1977 to 2008 I was a full-time professor in the business school at the University of San Francisco. My software projects have always been closely linked with my teaching and my desire to provide good and affordable tools to analysts in the business environment. My decision tree software has been included with fifty business textbooks used by undergraduates, MBAs, and Executive MBAs.

My business entity is Decision Toolworks, a sole proprietorship in San Francisco. I have been a part-time independent software vendor since 1991, and now it is more of a full-time endeavor. I lurk in the newsgroups of the Association of Shareware Professionals, and I attend the Software Industry Conferences. I also regularly participate in conferences of the relevant academic and professional organization, the Institute For Operations Research and the Management Sciences (INFORMS).

My primary product is TreePlan, a decision tree add-in for Excel. Decision trees are useful for analyzing sequential decision problems under uncertainty. TreePlan helps you build a decision tree diagram in an Excel worksheet using dialog boxes. TreePlan automatically includes formulas for summing cash flows to obtain outcome values and for calculating rollback values for determining optimal strategy.

TreePlan

Another important product is SensIt, a sensitivity analysis add-in. In a decision situation, sensitivity analysis helps you determine which of your input assumptions are critical so that you know where to focus your effort for gathering more information or reducing uncertainty. SensIt performs sensitivity analysis on your Excel worksheet what-if model. SensIt automates sensitivity analysis and creates simple plots, spider charts, and tornado charts.

SensIt

RiskSim, a Monte Carlo simulation add-in, fills out the product line. RiskSim provides random number generator functions as inputs for your Excel worksheet model, automates Monte Carlo simulation, and creates charts. RiskSim automates the simulation by trying thousands of what-ifs consistent with your assessment of the uncertainties and displays the results in both histogram and cumulative distribution charts.

You can download full-featured tryout versions of my software from http://www.TreePlan.com. I welcome questions and feedback via email This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Mike Middleton, Decision Toolworks