Question

1a

A teacher gives a third grade class of n = 16 a reading skills test at the beginning of the school year. To evaluate the changes that occur during the year, students are tested again at the end of the year. Their test scores revealed an average improvement of M_D = 4.7 points with SS = 2160.

Are the test scores at the end of the year significantly higher than the test scores at the beginning of the year.

Perform a hypothesis test using repeated-measures t-test. Use a one-tailed test with α = .01.

The alternative hypothesis in words is

Group of answer choices

a)The test scores at the end of the year are significantly different from the test scores at the beginning of the year

b)The test scores at the end of the year are not significantly higher than the test scores at the beginning of the year

c)The test scores at the end of the year are significantly higher than the test scores at the beginning of the year

d)The test scores at the end of the year are not significantly different from the test scores at the beginning of the year

e)The null hypothesis in symbols is

1b)Group of answer choices

a)H0: µD= 0

b)H0: µD≠ 0

c)H0: µ1> µ2

d)H1: µD> 0

e)H0: µ1= µ2

f)H0: µD≤ 0

1c)The critical t-value is

1d)The t-statistic is

Your decision is

a)Fail to reject the null hypothesis because the t-statistic is not greater than the critical t-value

b)Reject the null hypothesis because the t-statistic is greater than the critical t-value

c)Reject the null hypothesis because the t-statistic is not greater than the critical t-value

d)Fail to reject the null hypothesis because the t-statistic is greater than the critical t-value

1e) Construct a 99% confidence interval to estimate the average improvement for the population of third graders.

The lower boundary is:

The upper boundary of the confidence interval you constructed in the previous question is:

If all the possible random samples with n = 16 scores are selected from a normal population with µ = 80 and σ = 20, and the mean is calculated for each sample, then the Expected Value of M is _____ and the Standard Error of M is _____?

a) 80, 20

b) 80, 5

c) 20, 20

d) 5, 80

Answer 1

The paired standard deviation of t is

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Correct option is

c)The test scores at the end of the year are significantly higher than the test scores at the beginning of the year

1b)

a)H0: µD= 0

1c)

1d)

Decision:

a)Fail to reject the null hypothesis because the t-statistic is not greater than the critical t-value

1e)

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The Expected Value of M is

The Standard Error of M is