1. A researcher wanted to test how effective it is to be coached by a high-level...

1. A researcher wanted to test how effective it is to be coached by a high-level athlete. He had his participants show free throws at the beginning of the study. He then had Paul George coach his participants and they shot free throws again. He got the following data:


before paul george	after paul george
2	7
3	6
1	9
0	11
3	9
5	8

a. Identify the two groups:
b. State the null and research hypothesis:
c. Figure out the numbers you need:
What is N (the total number of DIFFERENCE SCORES)?
The population mean is always 0
What is the Mean Difference (the Sample mean)? _______________________
Now, what is the sum of squares? (X – M)2 ____________________________
What is the degrees of freedom? (N-1) _________
What is the variance? (X – M)2 / (N-1) _________________________
What is the standard deviation? s = (X – M)2 / (N-1)____________________
What is the standard error? sM = s/ (hint: use the standard deviation you just found) __________
Now, you have everything you need for
d. calculate the t-statistic (t = (M – μ)/sM) __________________________
e. What is the critical value? Use the value you got from N-1, and look for the number that is under .05 ___________________________
f. What decision do you make here? _______________________________________

Expert Solution

orchestra answered 2 years ago

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