5 5 5.5 5 5.5 9 7 8 9 6 7 8 8 7 8.5 Using Jamovi, and assuming we’re testing at an alpha of .05 (two-tailed), answer the following:  Degrees of freedom: ______________ Obtained test statistic: ________

Under what circumstances is a t statistic used instead of a z-score for a hypothesis test?     Justin wants to know whether a commonly prescribed drug does improve the attention span of students with attention deficit disorder (ADD). He knows that the mean attention span for students with ADD who are not taking the drug is 2.3 minutes long. His sample of 12 students taking the drug yielded a mean of 4.6 minutes. Justin can find no information regarding σx , so he calculated s2x =1.96. Determine the critical region using a one-tailed test with alpha = .05. Conduct the hypothesis test (Do the math and compare the t-critical and t-obtained values). State your conclusions in terms of H0 (Should you reject the H0 or fail to reject/accept the H0). Based on your analysis, is there a relationship between the drug and attention span?

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The following data were collected from a repeated-measures study. Perform an ANOVA. Use a .05 alpha level.                         Treatment                                             A        B                                           _____________                    G = 36              2          6                                                2          6                 ΣX2 = 192             4         4                                             4         8                                          ______________                                          T = 12   T = 24                                         SS = 4   SS = 8 1) State the null hypothesis. 2) Calculate necessary statistics (USE AN ANOVA even though K=2, and a = .05). 3) Make a decision about your null hypothesis and explain what that decision means. 4) Make a conclusion about your IV and DV that includes an APA format summary of your statistical analysis

A clinical trial is run to assess the effects of different forms of regular exercise on HDL levels in persons between the ages of 19 and 29. Participants in the study are randomly assigned to one of three exercise groups—weight training, aerobic exercise, or stretching/yoga—and instructed to follow the program for 8 weeks.  Their HDL levels are measured after 9 weeks and are summarized below.   Exercise Group N Mean Std Dev Weight Training 20 49.7 10.2 Aerobic Exercise 20 43.1 11.1 Stretching/Yoga 20 57.0 12.5   Complete the following ANOVA table.               Source of Error Sums of Squares df Mean Squares F Between           Within 6157.32       Total                                 1.Write the hypotheses to be tested.   2. Write the decision rule. Please find the F for the closest df   3. What is the conclusion?

Given the following data and using Jamovi, test (at an alpha of 0.05) whether type of music influences heart rate (measured in beats per minute, bpm).   Participant Rock Classical Heavy Metal ROW MEANS = 1 70 64 90 74.67 2 78 69 85 77.33 3 80 72 67 73 4 82 65 100 82.33 5 81 67 120 89.33 6 80 58 98 78.67 GROUP MEANS = 78.5 65.83 93.33   Total mean = 79.22   What are the degrees of freedom for between persons? ________ What is the critical value (from table): ___________________

Here are the data for an ANOVA experiment, and the APA Source table from Step 3 of that same ANOVA.  this information, Calculate the HSD value for a Tukey’s HSD test – including looking up the value of q from the table.  Use α = .05.   GROUP 1 GROUP 2 GROUP 3 GROUP 4 10 8 6 4 11 9 7 4 12 10 5 7 13 10 6 5   SOURCE SS df MS Fobt Between 107.19 3 35.73 27.22 Within 15.75 12 1.31   Total 122.94 15       Group of answer choices q = 4.20, HSD = 2.40 q = 6.20, HSD = 4.13 q = 4.53, HSD = 3.02 q = 5.53, HSD = 3.15