chisquare               R function for Chi-square, (N-1) Chi-square,
                        and G-Square test of independence, power
                        calculation, measures of association, and
                        standardised/moment-corrected
                        standardised/adjusted standardised residuals,
                        visualisation of odds ratio in 2xk tables
                        (where k >= 2)
diseases                Dataset: Cross-tabulation of quantity of
                        tobacco smoked daily vs. cause of death
safety                  Dataset: Cross-tabulation of people's feeling
                        of safety vs. town size
social_class            Dataset: Cross-tabulation of social class vs.
                        diagnostic category for a sample of psychiatric
                        patients
