Say I have the following college enrollment data:
In 1975, 188,234 men and 156,612 women were enrolled in California colleges.
In 2005, 194,416 men and 201,334 women were enrolled in California colleges.
In 1975, 132,261 men and 98,554 women were enrolled in Texas colleges.
In 2005, 140,082 men and 153,305 women were enrolled in Texas colleges.
Consider, for each state, the proportion of those enrolled in colleges who were female.
How would I go about computing the p-value for the null hypothesis that the 1975–2005 increase in this proportion was the same in Texas as in California?