Question

An article compared five different teaching methods for a particular course. The five methods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures, computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam. We are interested in finding out if the average test scores are different for the different teaching methods. Which of the following is the appropriate set of hypotheses? Select only one answer.

a) H0:μ1=μ2=μ3=μ4=μ5Ha:μ1≠μ2≠μ3≠μ4≠μ5

H0:μ1=μ2=μ3=μ4=μ5Ha:μ1≠μ2≠μ3≠μ4≠μ5

b) H0:sbetween=swithinHa:sbetween≠swithin

H0:sbetween=swithinHa:sbetween≠swithin

c) H0:μ1=μ2=μ3=μ4=μ5Ha: at least one pair of μi's differ.

H0:μ1=μ2=μ3=μ4=μ5Ha: at least one pair of μi's differ.

d) H0:μbetween=μwithinHa:μbetween≠μwithin

H0:μbetween=μwithinHa:μbetween≠μwithin

Answer 1

Given that,

An article compared five different teaching methods for a particular course. The five methods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures, computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam.

let,

Population mean of test scores for traditional lecture and discussion.

Population mean of test scores for  programmed textbook instruction.

Population mean of test scores for programmed text with lectures.

Population mean of test scores for computer instruction.

computer instruction with lectures.

Now we are interested in finding out if the average test scores are different for the different teaching methods.

i.e.

Null and Alternative hypotheses is given by,

At least one pair of differ.

Answer: Correct answer is " Option c "

[Note: Here we want to check is any one of the average score is different for different teaching methods so " option a " is incorrect.

For testing of hypothesis problem we can not take null and alternative hypotheses as within and between format so " option b and d " are incorrect. ]