Give one research example of when:           A) A one-sample t-statistic should be used?           B) An independent-measures t-statistic should be used?           C) A repeated-measure t-test should be used?

Perform the following hypothesis test of a proportion: HO: p = 0.125 HA: p 0.125 The sample proportion is 0.1 based on a sample size of 95.  Use a 10% significance level. What is the p-value?

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a) Which of the following is the correct test statistic for this test? b) Degrees of freedom for this test? c) P-value for this test?

A researcher wanted to test whether there is a relationship between preferred sweet (Oreo cookies, Mars bars, or Twinkies) and age group (children, adolescents, or young adults). To test that, subjects from the three age groups were asked which of the three sweets they preferred. Which statistical test should be used to analyze the data? 1. chi square test of independece  2. chi square test for goodness of fit 3.  one sample t test 4. one way anova test

1.Calculate the value of the test statistic  2. Determine the P-Value for the test statistic

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.

What statistical analysis could be used to determine whether the unsuccessful dieters attained a significantly different percentage from their weight-loss goal, on average, than did the successful dieters? single-sample t test In which of the following four categories does this situation fall? a. only scale variables b. nominal independent variables, scale dependent variable c. only nominal variables d. any ordinal variables (that cannot be treated as nominal)

A marketing director developed a short television commercial to improve the image of a company.  The commercial was tested on 20 people.  People’s attitudes about the company were measured with a questionnaire when they first came in for the experiment and then again with the same questionnaire after viewing the commercial.  Which statistical test would be best to determine if there is a significant difference between measures?     one-sample t-test     dependent samples t-test     independent samples t-test     ANOVA

a) Work this problem manually (by hand) using the procedures and formulas for ANOVA to check if the Population Means for flying time before major maintenance is required are the same for the three types of aircraft.   To help you, Sample Means and Sample Variances have been calculated below for you:                      Airbus                Boeing737            Boeing 787                        6.4                           8.7                          9.9                        7.8                           7.4                          12.8                        5.3                            9.4                         12.1                       7.4                            10.1                        10.8                       8.4                            9.2                          11.3                       7.3                            9.8                          11.5 __________________________________________________________________ Sample Mean         7.1…