Answer:
Step-by-step explanation:
Given : Sample size :
Sample mean :
Standard deviation :
Significance level :
Critical value :
Formula to find the confidence interval for population mean :-
Hence, a 90% confidence interval estimate of the population mean of all students =
Answer:
a) r = 0.974
b) Critical value = 0.602
Step-by-step explanation:
Given - Two separate tests are designed to measure a student's ability to solve problems. Several students are randomly selected to take both test and the results are give below
Test A | 64 48 51 59 60 43 41 42 35 50 45
Test B | 91 68 80 92 91 67 65 67 56 78 71
To find - (a) What is the value of the linear coefficient r ?
(b) Assuming a 0.05 level of significance, what is the critical value ?
Proof -
A)
r = 0.974
B)
Critical Values for the Correlation Coefficient
n alpha = .05 alpha = .01
4 0.95 0.99
5 0.878 0.959
6 0.811 0.917
7 0.754 0.875
8 0.707 0.834
9 0.666 0.798
10 0.632 0.765
11 0.602 0.735
12 0.576 0.708
13 0.553 0.684
14 0.532 0.661
So,
Critical r = 0.602 for n = 11 and alpha = 0.05
