Hypothesis Test for Effects of Marijuana Use on College Student: In a study of the effects of marijuana use , light and heavy users of marijuana in college were tested for memory recall with the results given below. Use a 0.05 significance level to test the claim that the population of heavy marijuana users has a standard deviation from that of light users.
Items sorted correctly by light marijuana users: n = 64, "x bar" = 53.3, s = 3.6
Items sorted correctly by heavy marijuana users: n = 65, "x bar" = 51.3, s = 4.5
#12 pg 481 Cigaretts Filters and Nicotine Refer to the sample result listed in the measured nicotine contents of randomly selected filtered and nonfiltered king size cigarettes. All measurements are in milligrams, and the data are from the Federal Trade Commission.
a. Use a 0.05 significance level to test the claim that king size cigarettes with filters have a lower mean amount of nicotine than the mean amount of nicotine in nonfiltered king size cigarettes.
b. Construct a 90% confidence interval estimate of the difference between the two population means
c. Do cigarette filters appear to be effective in reducing nicotine?
Kings Non Filter Kings
n1 = 21 n2 = 8
x(bar) =0.94 x2(bar) = 1.65
s1 = 0.31 s2 =0.16
Calculations for Testing Claims: In exercise 6 assume that you plan to use a significance level of 0.05 to test the claim that P1 = P2. Use the given sample sizes and numbers of successes to find (a) the pooled estimate "p bar" (b) the z test statistic (c) the critical z values and (d) the P-value
Low Activity High Activity
Stocks and Super Bowl Data Set 25 includes pairs of data for the Dow-Jones Industrial Average (DJIA) high value and total number of points scored in the Super Bowl for 21 different years. Excel was used to find that the value of the linear correlation coefficient is r = -0.133 and the regression equation is y (dependent variable) = 53.3 - 0.000442x, where x is the high value of the DJIA. Also the mean number of Super Bowl points is 51.4. What is the best predicted value for the total number of Super Bowl points scored in a year with a DJIA high of 1200?