Decision Rule The decision rule for the Spearman rank correlation will be to

# Decision rule the decision rule for the spearman rank

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Decision Rule The decision rule for the Spearman rank correlation will be to reject the null hypothesis if the observed value (rs) is equal to or greater than the critical value. Sample Problem: Ten (10) instructors were rated by the 3rd and 4th year college students on their“mastery of the subject matter” and the results were tabulated. What is the Spearmanrho value for the data?  ) = 1- ("1293" /( 990) ) = 1- 1.31 rs = -0.31 Step 6 Table of critical values for critical significance levels (a ; alpha) Decision Rule Step 7 The critical value can be found in a Table of critical values for Critical Significance Level (a: alpha) of 0.1, 0.05 and 0.01 . In order to determine the critical value of rs, we need to get the degrees of freedom, df = n-2 . In the given example, df = 10-2 =8. The critical value is 0.648 and the decision rule is to reject H if calculated value is equal to, or more than the critical value , rs ≥ 0.648. Strength: Therefore, there is weak, negative correlation between 3rd and 4th year college students. means the closer the value to the -1, the negative result of correlation it has. Conclusion: Step 8 and 9 We fail to reject the H because rs , -0.31 < 0.648 indicates at a = 0.05 to show that there is no significant difference in the ratings given by the students to their instructors. This means that the values given by the 3rd year and 4th year students are not correlated or not affected by each other’s ratings to their 10 instructors. #### You've reached the end of your free preview.

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• Summer '17
• Rachelle
• Correlation, Null hypothesis, Pearson product-moment correlation coefficient, critical value, Spearman's rank correlation coefficient
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