Twenty students were recruited to take part in a writing study. The 10 students randomly assigned to an expressive writing group wrote about their thoughts and feelings associated with their most traumatic life events. The 10 students randomly assigned to the control group wrote about their plans for the day. One month later, all the students rated their overall level of physical health on a scale from 0 = very poor health to 100 = perfect health. The researchers were interested in whether there was a positive or a negative health effect of expressive writing. Thus, the research hypothesis was that Population 1 students would rate their health differently than Population 2 students. The null hypothesis was that Population 1 students would rate their health the same as Population 2 students. Conduct a hypothesis test at the .05 level using the data below. What would you conclude? Show all steps and calculations. Expressive Writing Group Mean = 79 n1 = 10 SĀ² = 94.44 Control Group Mean = 68 n2 = 10 SĀ² = 111.33
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The research hypothesis is that the expressive writing group (Population 1) would rate their health differently than the control group (Population 2). The null hypothesis is that there is no difference in health ratings between the two groups. Show moreā¦
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