
Concept explainers
Terminology Consider the graph of a
(i) The graph is bell-shaped, with the highest point over the p.
(ii) The graph is symmetrical about a vertical line through
(iii)The graph crosses the horizontal azis at
(iv)The area under the graph to the right of
(v) The probability that x is between a and b is the area under the curve between a and b.
(i)

The statement “The graph of a normal probability distribution is bell-shaped, with the highest point over the
Answer to Problem 1CR
Solution: The statement “The graph of a normal probability distribution is bell-shaped, with the highest point over the
Explanation of Solution
The graph of a normal probability distribution is bell-shaped, with the highest point over the
(ii)

The statement “The graph of a normal probability distribution is symmetrical about a vertical line through
Answer to Problem 1CR
Solution: The statement “The graph of a normal probability distribution is symmetrical about a vertical line through
Explanation of Solution
The graph of a normal probability distribution is symmetrical about a vertical line through
(iii)

The statement “The graph of a normal probability distribution crosses the horizontal axis at
Answer to Problem 1CR
Solution: The statement “The graph of a normal probability distribution crosses the horizontal axis at
Explanation of Solution
The graph of a normal probability distribution crosses the horizontal axis at
(iv)

The statement “The area under the graph of a normal probability distribution to the right of at
Answer to Problem 1CR
Solution: The statement “The area under the graph of a normal probability distribution to the right of at
Explanation of Solution
The area under the graph of a normal probability distribution to the right of at
(v)

The statement “The probability that x is between a and b is the area under the curve between a and b” is true or false.
Answer to Problem 1CR
Solution: The statement “The probability that x is between a and b is the area under the curve between a and b” is true.
Explanation of Solution
The probability that x is between a andb is the area under the curve between a and b is true. The curve used to describe the distribution of a continuous random variable is called probability distribution curve. It tells what proportion of the population falls within any given interval.
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Chapter 7 Solutions
Understanding Basic Statistics
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- Please conduct a step by step of these statistical tests on separate sheets of Microsoft Excel. If the calculations in Microsoft Excel are incorrect, the null and alternative hypotheses, as well as the conclusions drawn from them, will be meaningless and will not receive any points 2. Two-Sample T-Test: Compare the average sales revenue of two different regions to determine if there is a significant difference. (Hints: The null can be about maintaining status-quo or no difference among groups; if alternative hypothesis is non-directional use the two-tailed p-value from excel file to make a decision about rejecting or not rejecting null) H0 = H1=arrow_forwardPlease conduct a step by step of these statistical tests on separate sheets of Microsoft Excel. If the calculations in Microsoft Excel are incorrect, the null and alternative hypotheses, as well as the conclusions drawn from them, will be meaningless and will not receive any points 3. Paired T-Test: A company implemented a training program to improve employee performance. To evaluate the effectiveness of the program, the company recorded the test scores of 25 employees before and after the training. Determine if the training program is effective in terms of scores of participants before and after the training. (Hints: The null can be about maintaining status-quo or no difference among groups; if alternative hypothesis is non-directional, use the two-tailed p-value from excel file to make a decision about rejecting or not rejecting the null) H0 = H1= Conclusion:arrow_forwardPlease conduct a step by step of these statistical tests on separate sheets of Microsoft Excel. If the calculations in Microsoft Excel are incorrect, the null and alternative hypotheses, as well as the conclusions drawn from them, will be meaningless and will not receive any points. The data for the following questions is provided in Microsoft Excel file on 4 separate sheets. Please conduct these statistical tests on separate sheets of Microsoft Excel. If the calculations in Microsoft Excel are incorrect, the null and alternative hypotheses, as well as the conclusions drawn from them, will be meaningless and will not receive any points. 1. One Sample T-Test: Determine whether the average satisfaction rating of customers for a product is significantly different from a hypothetical mean of 75. (Hints: The null can be about maintaining status-quo or no difference; If your alternative hypothesis is non-directional (e.g., μ≠75), you should use the two-tailed p-value from excel file to…arrow_forward
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