INFORMATION AND ANALYSIS

Answers, Ch. 10

10.11

a. 

H₀:  m₁ ≤ m₂  =>  H₀:  m₁ - m₂ ≤ 0
H₁:  m₁ > m₂ =>   H₁:  m₁ - m₂ > 0

α = 0.05, n₁ = 1000, n₂ = 1000

α = 0.05 => Reject H₀ if t_n1+n2-2  > 1.645

=> Reject H₀, accept H₁

b. Usually not possible to calculate p-value without a computer, but the calculated t value is so high that p-value = 0.0000.  The lowest level of " where the H₀ can be rejected is 0.0000.

c. Skip

10.33

H₀:  π₁ = π₂  =>  H₀:  π₁ - π₂ = 0
H₁:  π₁ ≠ π₂ =>   H₁:  π₁ - π₂ ≠ 0

α = 0.01, n₁ = 240, n₂ = 224

α = 0.01 => Reject H₀ if Z > 2.576 or < -2.576

p₁ = x₁ / n₁ = 136 / 240 = 0.57, p₂ = x₂ / n₂ = 224 / 260 = 0.86

=> Reject  H₀, accept H₁