Chi Square Test Hypothesis: the genes are not linked Prediction: the progeny should be in a 1: 1: 1: 1 ratio x test: obs exp (obs-exp)/exp 283 809 342.0 1294 809 290.8 1418 809 458.4 241 809 398.8 Total 3236 3236 1490.0 Degrees of freedom=4-1=3 one less than the number of progeny classes)Chi Square Test • Hypothesis: the genes are not linked. • Prediction: the progeny should be in a 1:1:1:1 ratio. •  2 test: obs exp (obs-exp)2 /exp 283 809 342.0 1294 809 290.8 1418 809 458.4 241 809 398.8 Total 3236 3236 1490.0 • Degrees of freedom = 4 -1 = 3 (one less than the number of progeny classes)