2. The average score on an exam is 78. A test is given to 40 students...

2. The average score on an exam is 78. A test is given to 40 students and the average on the exam was 82 with a standard deviation of 14.

a) At the .01 level did the students do better than expected? (p = .039)

b) How do you explain the 4 point increase?

C) Interpret the p-value:

D) What is the only type of error that could have occurred

Solutions

Expert Solution

It may due to chance alone or it may possible only students very good in studies were in the sample.

It shows the probability of getting sample results or more extreme results under the assumption that null hypothesis is true.

Since we fail to reject the null hypothesis so type II error is possible.

orchestra answered 11 months ago

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