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NEW! Global nonlinear regression with Prism 4. This seven page article summarizes global fitting, and shows how it is used in five situations, including computing a pA2 from how an antagonist shifts a dose-response curve, and how to analyze homologous radioligand binding experiments. View the pdf.

Fitting models to biological data using linear and nonlinear regression. A practical guide to curve fitting. This book, written by Harvey Motulsky (GraphPad) and Arthur Christopoulos (Univ. Melbourne), will be included with Prism 4. While most of the information included will be useful to people who use Prism 3 or any other curve fitting program, some of the information is specific to Prism 4 which we plan to release in early 2003. View the pdf, 350 pages.

Prism 4 Step-By-Step Examples, a 200 page book that explains how to perform twenty common analyses using Prism. These examples teach Prism and demonstrate many useful techniques and features in the program. The entire book is available as a free pdf file to browse online or print. You may also read access these examples in the Prism section of this site.

Prism 4 Statistics Guide, a 150 page book that explains how to perform statistical analyses with Prism. Only about 10% of this book is specific to Prism. The rest explains statistical concepts to help you pick a test and make sense of the results. The entire book is available as a free pdf file to browse online or print.

The Prism Guide to Interpreting Statistical Results: This guide is excerpted from Analyzing Data with GraphPad Prism, a book that accompanies the program GraphPad Prism. Browse topics using the links below. You may also download the entire book.

• Bayesian Approaches
• Confidence Intervals
• How to Interpret Results
• Multiple Comparisons
• Power
• P values
• Statistical Significance

Intuitive Biostatistics: Master the principles of statistics and the scientific interpretation of statistical tests. Intuitive Biostatistics was written by GraphPad's president Harvey Motulsky. Read these excerpts online:

• Choose an appropriate statistical test
• Survival Curves
• Comparing Two Survival Curves
• Interpreting Nonsignificant P Values
• Multiple Comparisons

Articles:

• Multicollinearity
• Error bars and statistical significance
• Detecting outliers
• Comparing curves

Presentations: (PowerPoint sides)

• Advances in curve fitting with Prism 4 (Presented at FASEB, April 2003, 2 hours)
• Global curve fitting. Better results, less work. (Presented at Great Laks GPCR Retreat, Oct. 2002, 45 min.)
• Advantages of global curve fitting. (Presented as AstraZeneca UK, Sept. 2002, 20 mimn)
• Nonlinear regression for phamacologists. (Presented as AstraZeneca UK, Sept. 2002, 1hr)
• Parameter sharing with Prism 4. (Presented at IUPHAR, August 2002.)
• Troubleshooting nonlinear regression. (Presented at IUPHAR, August 2002).

Booklets: These concise booklets, written by GraphPad's president Harvey Motulsky, provide clear explanations to these common analysis topics:

• The GraphPad Guide to Nonlinear Regression.
• The GraphPad Guide to Radioligand Binding.

CurveFit.com was created by GraphPad as a comprehensive nonlinear regression resource. Explore dozens of relevant topics, including analysis of dose-response, radioligand binding, enzyme kinetic data and much more.