1.
To test: The
1.
Answer to Problem 1TP
Explanation of Solution
Given information: The correlation between speed and strength for 20 women is 0.57.
Calculation:
The claim is:
The null hypothesis is given by;
The alternative hypothesis is given by;
The tabulated value is calculated at 1% level of significance and tail is one tailed.
The tabulated value is 0.515 and calculated or obtained value of correlation is 0.57.
Conclusion:
The calculated or obtained value of correlation is greater than tabulated value at 1% level of significance. The null hypothesis is rejected at 1% level of significance. Therefore, there is a significance difference between speed and strength for 20 women. This shows that speed of women affecting the strength of women.
2.
To test: The correlation between the number correct on a math test and the time is taken to complete the test.
2.
Answer to Problem 1TP
Explanation of Solution
Given information: The correlation between the number correct on a math test and the time it takes to complete the test is -.45.
Calculation:
The claim is:
The null hypothesis is given by;
The alternative hypothesis is given by;
The tabulated value is calculated at 5% level of significance and tail is one tailed.
The tabulated value is 0.1829 and calculated or obtained value of correlation is -0.45.
Conclusion:
The calculated or obtained value of correlation is less than tabulated value at 5% level of significance. The null hypothesis is not rejected at 5% level of significance. Therefore, there is no significance difference between the number correct on a math test and the time is taken to complete the test. This means that more number of corrections on math test needs more time.
3.
To test: The correlation between number of friends and grade point average (GPA) for 50 adolescents.
3.
Answer to Problem 1TP
Explanation of Solution
Given information: The correlation between number of friends and grade point average (GPA) for 50 adolescents is .37.
Calculation:
The claim is:
The null hypothesis is given by;
The alternative hypothesis is given by;
The tabulated value is calculated at 5% level of significance and tail is a two tailed.
The tabulated value is 0.273 and calculated or obtained value of correlation is 0.37.
Conclusion:
The calculated or obtained value of correlation is greater than tabulated value at 5% level of significance. The null hypothesis is rejected at 5% level of significance. Therefore, there is a significance difference between the number of friends and grade point average (GPA) for 50 adolescents.
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Chapter 15 Solutions
Statistics for People Who (Think They) Hate Statistics, Salkind, Without CD
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