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Chapter 10: Q. 92 (page 602)

92. Suppose a statistics instructor believes that there is no significant difference between the mean class scores of statistics day students on Exam 2 and statistics night students on Exam 2. She takes random samples from each of the populations. The mean and standard deviation for 35 statistics day students were 75.86 and 16.91, respectively. The mean and standard deviation for 37 statistics night students were 75.41 and 19.73. The "day" subscript refers to the statistics day students. The "night" subscript refers to the statistics night students. An appropriate alternative hypothesis for the hypothesis test is:
a. μday>μnight
b. μday<μnight
c. μday=μnight
d. μday≠μnight

Short Answer

Expert verified

The correct answer is option (d) μday≠μnight.

Step by step solution

01

Given information

Let, the mean and standard deviation for 35statistics day students were 75.86and 16.91, respectively. And the mean and standard deviation for 37statistics night students were 75.41and 19.73.

02

Explanation

The statistics instructor considers there is insufficient evidence between the class mean of statistics day on Exam 2and statistics night on Exam 2,
As a result, the alternative hypothesis has two tails.
The following is an alternative hypothesis:
μday≠μnight
Therefore, the correct answer is option (d).

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Most popular questions from this chapter

Weighted alpha is a measure of risk-adjusted performance of stocks over a period of a year. A high positive weighted alpha signifies a stock whose price has risen while a small positive weighted alpha indicates an unchanged stock price during the time period. Weighted alpha is used to identify companies with strong upward or downward trends. The weighted alpha for the top 30 stocks of banks in the northeast and in the west as identified by Nasdaq on May 24,2013 are listed in Table 10.6 and Table10.7, respectively

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g. What is the p-value?

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In words, define the random variable for this test.
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