McGraw Hill
Glencoe: Self Check Quizzes 1 Frequency Tables
Use Glencoe's randomly generated self-checking quiz to test your knowledge of frequency tables. Each question has a "Hint" link to help. Choose the correct answer for each problem. At the bottom of the page click the "Check It" button...
Rice University
Hyper Stat Online Statistics Textbook: Contingency Table
A brief explanation and example of what a statistical contingency table is.