Can people really identify their favorite brand of cola? Volunteers tasted Coca-Cola Classic, ...

 Can people really identify their favorite brand of cola? Volunteers tasted Coca-Cola Classic, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below. Research question: At α = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you identify your favorite brand in this kind of test? Since it is a 2 × 2 table, try also a two-tailed two-sample z test for π1 = π2 (see Chapter 10) and verify that z2 is the same as your chi-square statistic. Which test do you prefer? Why?
Correct? Regular Cola Diet Cola Row Total
Yes,got it right 7 7 14
No, got it wrong 12 20 32
Col Total 19 27 46