statistics and probability

5:38 S S S (d) Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis? Are the data statistically X 0.4 nilIWA - Tests IIIVOL... ignificant at level cc? . .. O At the ex - 0.05 level we reject the null hypot a are statistically significant webassign.net O At the ex = 0.05 level, we fail to data are statistically significant At the ex - 0.05 level we re statistically significant. At the ex = 0.05 level, we f ta are not statistically significant. 10. [-/1.5 Points] DETAILS BBUNDERSTAT12 8.4.020.5. (e) State your conclusion in the context of the application. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER O Reject the null hypothesis, there is sufficient evidence to claim that the meant In this problem, assume that the distribution of differences is approximately normal. Note: For degrees of freedom d.f. not in the Fail to reject the null hypothesis, th Student's t table, use the closest dif. that is smaller, In some situations, this choice of dif. may increase the Pvalue by a small amount rewards to run the and therefore produce a slightly more "conservative" answer. maze is less. Fail to reject the null hypothesis, there is insuffic receiving larger rewards to run the In an effort to determine if rats perform certain tasks more quickly if offered larger rewards, the following experiment was performed. maze is less. On day 1, a group of three rats was given a reward of one food pellet each time they ran a maze. A second group of three rats was given a reward of five food pellets each time they ran the maze. On day 2, the groups were reversed, so the first group now got five food Reject the null hypothesis, there is ger rewards to run the maze 19 legs. pellets for running the maze and the second group got only one pellet for running the same maze. The average times in seconds fo each rat to run the maze 30 times are shown in the following table. Need Help? Read It Rat Time with one food pellet 3.5 Time with five food pellets 2.4 LA USE SALT 11. [-/1 Points] DETAILS BBUNDERSTAT12 8.4.022.MI.S. Do these data indicate that rats receiving larger rewards tend to run the maze in less time? Use a 5% level of significance. (Let d - one - five.) MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER (a) What is the level of significance? Using techniques from an earlier section, we can find a confidence interval for Leg. Consider a random sample of n matched data pairs A, B. Let a = 8 - A be a random variable representing the difference between the values in a matched data pair. Compute the sample State the null and alternate hypotheses. Will you use a left-tailed, right-tailed, or two-tailed test? mean a of the differences and the sample standard deviation s. If d has a normal distribution or is mound-shaped, or if n 2 30, then a Hey-QH, My FO two-tailed confidence interval for At, is as follows. OH my= 0 Hy: 14y * 0; left-tailed OH My- OH, My > D: right-tailed 2 - Espycate OHMy * 0, H,: Hy = D; left-tailed where E = te for G- confidence level [Dec = 1) 6) What sampling distribution will you use? What assumptions are you making The standard normal. We assume that of has an s to * critical value for confidence levele and df. = n - 1 proximately normal distribution The standard normal. We assume that d has an approximately uniform distribution. The Student's 1. We assume that d uniform distribution. 8: Percent increase for company 16 16 12 19 6 4 21 37 The Student's T. We assume that d hately normal distribution A: Percent increase for CEO 26 20 78 16 -4 19 15 20 What is the value of the sample test statistic? (Round your answer to three decimal places.) LA USE SALT (c) Find (or estimate) the P-value. Pvalue > 0.250 (a) Using the data above, find a 95% confidence interval for the mean difference between percentage increase in company revenue and 0.125