8.42 Sample size needed for an evaluation. You are planning an evaluation of a semester-long alcohol awareness campaign at your college. Previous evaluations indicate that about 20% of the students surveyed will respond Yes to the question "Did the campaign alter your behavior toward alcohol consumption?" How large a sample of students should you take if you want the margin of error for 95% confidence to be about 0.07?

The Bureau of Labor Statistics reports that the official unemployment rate for Black people was 10.4% and 4.7% for White people in February 2015. Select all correct answers for this question. O The samples of white and black people are independent. The explanatory variable is the unemployment rate. The response variable is the unemployment rate. The response variable is race.

During the 1990s, the fatality rate for lung cancer was 80 per 100,000 people. After the turn of the century and the establishment of newer treatments and adjustment in public health advertising, a random sample of 10,000 people exhibits only six deaths due to lung cancer. Test at the 0.05 significance level whether that data are proof of a reduced fatality rate for lung cancer. b. Make the decision rule. (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)  c. Evaluate the test statistic. (Negative amount should be indicated by a minus sign. Round your answer to 3 decimal places.)

A study compared the felt intensity of unrequited love among three groups​ - individuals who were currently experiencing unrequited​ love, those who had previously experienced unrequited love and described their experiences​ retrospectively, and those who had never experienced unrequited love but described how they thought they would feel if they were to experience it. The results of the study are summarized in the accompanying table. Determine the significance of the difference among​ groups, using the​ 5% level.    N 40 40 40 M 3.5 3.3 3.7 S2 5.3 5.8 4.8   1. What is th null hyp?  2.The comparison distribution will be an F distribution with df= ? and df=?  3.Determine the cutoff sample score on the comparison distribution at which the null hypothesis should be rejected for the data. At 0.05  the cutoff for F=? 4. Determine the​ sample's score on the comparison distribution for the data. F=?

4. At private college the achievement test is used for advanced study placement. Counselors selected a random sample of 144 students from the college and scored their tests by hand before sending them in for computer processing. For this sample, the mean was 450 and s = 29. Construct a 98% confidence interval for the mean.

According to a report on consumer fraud and identity theft, 22% of all complaints for a year were for identity theft. In that year, Wisconsin had 787 complaints of identity theft out of 3498 consumer complaints. Does this data provide enough evidence to show that Wisconsin had a higher proportion of identity theft than 22%? Test at the 1% level. State the hypotheses. Ho: p? v Ha: p|? v Calculate the test statistic. Round to four decimal places. Calculate the standardized test statistic. Round to three decimal places. Z = Find the p-value. Round to four decimal places. p-value = State your decision. O Since the p-value is less than .01, reject Họ. O Since the p-value is greater than .01, reject Ho. O Since the p-value is less than .01, fail to reject Ho. O Since the p-value is greater than .01, fail to reject Ho. Interpret the results. O At the 1% level of significance, there is enough evidence to show that the proportion of complaints due to identity theft in Wisconsin is not equal to…

A chemist measures the haptoglobin concentrations (in grams per liter) in the blood of eight healthy adults.  Following are the values: 1.82   3.32   1.07   1.27   0.49   3.79   0.15   1.98  At the 2% significance level, test the claim that the mean haptoglobin concentration in adults is less than two grams per liter.    What type of error could you have made in your decision?

If sample data is such that for a one-tailed test of ? you can reject H0 at the 1% level of significance, can you always reject H0 for a two-tailed test at the same level of significance? Explain your answer?   A. Yes. If H0 for a one-tailed test is rejected at the 1% level of significance, it will always be rejected for a two-tailed test at the same level of significance. B. No. If H0 for a one-tailed test is rejected at the 1% level of significance, it will never be rejected for a two-tailed test at the same level of significance.     C. Yes. The P-value for the two-tailed test could be greater than 0.01. D. No. The P-value for the two-tailed test could be greater than 0.01.

Which test statistic should be used to analyze the data?

Consider the relationship between p-values and significance levels. a. Explain why a value of z-statistic that is significant at the 1% level in a one-sided test is always significant at the 5% level. b. Explain why the reverse is not true. If something is significant at the 5% level in a one-sided test it is not necessarily significant at the 1% level.