A two-tailed test of H0:ρ=0H_0:\rho=0H0:ρ=0 is carried out using 22 paired observations. The observed value is r=−0.515r=-0.515r=−0.515. The two-tailed p-value is 0.0142.
Complete the test at the 2% significance level.
Without further calculation, state the conclusion at the 1% significance level.
Explain why replacing the alternative hypothesis by H1:ρ<0 H_1:\rho<0\,H1:ρ<0 after seeing the data would be inappropriate.
178 exam-style questions on WJEC A Level Maths 4.3.1 Statistical hypothesis testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.