we run a hypothesis test for the difference of two means mu1 and mu2, with an alternative hypothesis of mu1 < mu2.  And suppose that the test statistic is t = -1.68 (and the t-model has 20 degrees of freedom).  What is the p-value for this test?

An experiment was conducted to test the effect of a new cholesterol medicine. Fifteen people were treated with medicine X and 15 with medicine Y for a month, then the subjects' cholesterol level was measured. A significance test was conducted at the a = 0.01 level for the difference in the means of the cholesterol levels between medicine X and medicine Y. The test resulted in t = 2.73 and p = 0.003. If the alternative hypothesis in question was Ha: px - μy ‡ 0, where µx equals the mean cholesterol level for subjects taking medicine X and μy equals the mean cholesterol level for subjects taking medicine Y, what conclusion can be drawn? O There is not a significant difference in mean cholesterol level when using medicine X and medicine Y. O There is sufficient evidence that there is a difference in mean cholesterol level when using medicine X and medicine Y. O There is sufficient evidence that medicine X lowers cholesterol levels more than medicine Y. O The proportion of subjects who…

Imagine that your null hypothesis is σ2 = 10 and your alternative hypothesis is σ2 > 10. What is the critical value for the test statistic  given α = 0.05 and n = 12?

Previously, 8.3​% of workers had a travel time to work of more than 60 minutes. An urban economist believes that the percentage has increased since then. She randomly selects 50 workers and finds that 10 of them have a travel time to work that is more than 60 minutes. Test the​ economist's belief at the α=0.05 level of significance. Find the P-value.

Suppose we want to test the null hypothesis H0 : p1 − p2 = 0 against the alternative hypothesis Ha : p1 − p2 < 0 at the 5% level of significance.  Suppose also that x1  = 70, n1 = 100, x2 = 90, n2 = 120.  What is the observed test statistic for this   test?

A random sample of 15 families representing three different Scandinavian countries has been observed for the number of weekend trips they take per year. Are the differences significant (use p=.05, F(critical) = 3.88)? Use the five step model as a guide and write a sentence or two of interpretation for your results.   Sweden Norway Denmark 10 11 7 9 10 5 4 5 2 2 2 0

a researcher uses a sample of n=25 individuals to evaluate the effect of a treatment. the hypothesis test uses a=0.05 and produces a significant result  with t=2.15. how would this result be reported in the literature?

A track coach is trying to decide whether to recommend a new running shoe by Converse or his preferred shoe by Nike. The coach decides to recruit four of his runners to run one kilometer with each shoe type. The coach spreads his experiment over two days, to allow his runners to rest. Below are the run times in minutes. Are the run times for the two types of shoes different? Does it matter? states null and alternative hypothesis, an alpha level of 0.05 test null hypothesis, draw rejection region, effect size, conclusion  Table below  Converse  Nike  4.4 4.1 4.7 4.8 4.8 4.1 4.4 4 4.1 3.9

An experiment was conducted to test the effect of a new stain remover. Twenty stains were treated with stain remover A and stain remover B for a week, then the number of stains removed was measured. A significance test was conducted at the a = 0.10 level for the difference in the means of the number of stains removed between stain remover A and stain remover B. The test resulted in t = 1.37 and p = 0.17. If the alternative hypothesis in question is Ha: HA - HB #0, where μA equals the mean number of stains removed with stain remover A and μg equals the mean number of stains removed with stain remover B, what conclusion can be drawn? O There is a significant difference in the mean effectiveness of two stain removers. O There is sufficient evidence that stain remover A works better than stain remover B. O The proportion of stains that stain remover A removed is greater than the proportion of stains removed by stain remover B. O There is insufficient evidence that the proportion of stains…

A researcher wanted to examine the effectiveness of Vitamin C on the number of colds a year. The researcher obtained a sample of adults and asked to take Vitamin C daily. The average number of colds a year among adults is known to have the average of μ = 3On the basis of this sample, can the researcher conclude that Vitamin C has an effect on the number of colds a year? Use alpha =.05 two-tailed test. Colds: 2,2,2,1,3,3,1,2 Conducta two-tailed test with alpha = .05. Q1: State your null and research hypotheses using complete sentences Q2: What is the df? Q3: What are the cut-off points Q4: What is the standard deviation? You can just include the answer for the mean, SS, and the standard deviation. No need to type your computation. Q5: What is the estimated standard error? Show your computation. Q6: What is the t-value? Show your computation. Q7: State your conclusion thoroughly.