The application allows you introduce and modify data of a contingency table (2 x 2) and analyse the relationship between two ordinal or nominal dichotomous variables.

The option "observed" shows the table of data introduced with marginal totals.

The option "expected" shows the table of expected data.

The option "chi square" shows the table with observed data, expected data, differences, square differences and the quotients between square differences and expected values which total sum is the chi square estimated.

If the value of chi square is high enough we can reject the null hypothesis and say that probably the differences are significant and there is a relationship between the two variables.

In the example you see when the application is installed, we can say that probably there are significant differences between men and women buying in internet at Spanish homes.