ESS210B
Prof. Jin-Yi Yu
Another Example
qIn a study of the correlation between the amount of rainfall and the quality of air pollution removed, 9 observations were made. The sample correlation coefficient is –0.9786. Test the null hypothesis that there is no linear correlation between the variables. Use 0.05 level of significance.
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qAnswer:
q     1.  Ho: r = 0;  H1: r¹ 0
q     2.  a = 0.05
q     3.  Use Fisher’s Z
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q     4. Z < Z 0.025 (= -1.96)  è  Reject the null hypothesis
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