Can people really identify their favorite brand of cola? Volunteer tasted coca-cola classic, pepsi, Diet coke, and Diet pepsi, with the results shown below. Research question: At a = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you idenytify your favorite brand in this kind of test? Since it is a 2x2 table, try also a two-tailed two sample z test )(1 =)(2
Correct Regulat Cola Diet Cole Row Total
yes got it right 7 7 14
no got it wrong 12 20 32
Col Total 19 27 46