Conduct Web experiments using PHP, Part 2
By Paul Meagher2005-03-18
2x2 contingency tables
If you decided to conduct your Web offer study using a sample size of 400 visitors, you might observe the following response totals (joined=y) for the two levels of your IMAGE and TEXT factors (or, your four factorially constructed ad banner versions):
Table 2. Tabular summary of Web offer results
| TEXT | ||||
| short | long | sum | ||
| IMAGE | person | 2 | 8 | 10 |
| product | 6 | 2 | 8 | |
| sum | 8 | 10 | 18 | |
Table 2 is called a 2x2 contingency table and you will learn how to simulate and analyze the count data appearing in it.
Tutorial Pages:
» Categorical data analysis
» 2x2 contingency tables
» Sampling model
» Discrete probability distributions
» Binomial sampling model
» Poisson sampling model
» Envisioning your results
» Eliciting your prior distribution
» Model fitting with chi-square
» Null effects model
» Independence model
» Prior model
» DOE explorer
» Explorer output
» Conclusions
» Resources
First published by IBM developerWorks
