Part II

Getting Down and Dirty with Data

Illustration by Wiley, Composition Services Graphics

Read about two views of probability — the frequentist view and the Bayesian view — in an article at www.dummies.com/extras/biostatistics.

In this part . . .

  Collect and validate your data, avoiding common pitfalls upfront that can cause trouble later on.

  Summarize your data in informative tables and display it in easy-to-understand graphs.

  Understand the concepts of accuracy and precision. (In a nutshell: Accuracy refers to how close a sample statistic tends to come to the corresponding population parameter, and precision refers to how close replicate values of a sample statistic are to each other.)

  Calculate standard errors and confidence intervals for everything you measure, count, or calculate from your data.