8.- Many studies have been conducted to test the effects of marijuana use on mental abilities. In onesuch study, groups of light and heavy users of marijuana in college were tested for memory recall, withthe summary results given below.MarijuanaLight UseHeavy UseMeanStandard Deviationni = 65n2 = 65X1 = 53.3X1 = 51.3S1 = 3.6S1 = 4.5a) Use a 0.01 significance level to test the claim that the population of heavy marijuana users has alower mean than the light users.Answer: Ho:Hạ:CV =RR =Test statistics =P-value =Conclusion: Keep H.Does the result of the hypothesis test suggest using marijuana be of concern to college students?Reject H.YESNOb) Construct a 98% confidence interval for the difference between the two population means.Answer:Based on the results, should there be a concern about using marijuana be of concern to collegestudents?YESNOHian hornital

Solution We will use t distribution to find CI.

Answered: 8.- Many studies have been conducted to…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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A Michigan study concerning preference for outdoor activities used a questionnaire with a six-point Likert-type response in which 1 designated "not important" and 6 designated "extremely important." A random sample of n1 = 41 adults were asked about fishing as an outdoor activity. The mean response was x1 = 4.9. Another random sample of n2 = 50 adults were asked about camping as an outdoor activity. For this group, the mean response was x2 = 5.7. From previous studies, it is known that ?1 = 1.6 and ?2 = 1.5. Does this indicate a difference (either way) regarding preference for camping versus preference for fishing as an outdoor activity? Use a 5% level of significance.Note: A Likert scale usually has to do with approval of or agreement with a statement in a questionnaire. For example, respondents are asked to indicate whether they "strongly agree," "agree," "disagree," or "strongly disagree" with the statement. (a) What is the level of significance? .05 State the null and alternate…
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any studies have been conducted to test the effects of marijuana use on mental abilities. In one such study, groups of light and heavy users of marijuana in college were tested for memory recall, with the results given below. Use a a 0.05 significance level to test the claim that in the population of heavy marijuana users, the mean number of items sorted correctly is lower than the mean number in the population of light users. Items sorted correctly by light marijuan users: n = 64, x overbar equals 53.5 , s = 3.6 Items sorted correctly by heavy marijuan users: n = 65, x overbar equals 51.3 , s = 4.5 a. Define the parameters A. p 1 equals The proportion of light marijuana users p 2 equals The proportion of heavy marijuana users B. mu 1 equals The mean number of light marijuana users mu 2 equals The mean number of heavy marijuan users C. p 1 equals The proportion of items sorted correctly by all light…

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