Author:
Christine Farr

Space Lab Life Science ExperimentIn an experiment 28 male rats were randomly assigned to one of two groups. The 14 male rats in Group1 were sent into space. Upon their return, their red blood cell mass (in milliliters, mL) was determined.The 14 male rats in Group 2 (the control group) were held in the science lab at Cape Kennedy.Unfortunately, one of the rats in the control group died during the experiment, so the sample sizes were14 and 13, respectively. The descriptive statistics were obtained at the conclusion of the mission and areprovided in the table. The data analyst would like to use the data to produce a 95% confidence intervalfor the difference in the population mean red blood mass, μ1 - μ2.1.aAfter examining the two sample standard deviations, the analyst decided to also look at Levene’s testresult to help assess if the population variances can be considered equal. The p-value for Levene’s testwas 0.055. Using the 10% significance level for Levene's test, which technique is reasonable to use formaking the confidence interval estimate?Pooled 95% confidence intervalGeneral (unpooled) 95% confidence interval1.bProduce the corresponding 95% confidence interval for the difference in the population mean redblood cell mass, μ1 - μ2. Show your work. Interpret your interval in context.1.cThe analyst observes that the value of 0 does fall in the 95% confidence interval. As a result of this95% confidence interval, which conclusion is appropriate at the 5% level of significance?It appears the population mean red blood cell mass for male rats sent into space is less than thepopulation mean red blood cell mass for male rats not sent into space.There does not appear to be a difference between the population mean red blood cell mass for male ratssent into space and the population mean red blood cell mass for male rats not sent into space.It appears the population mean red blood cell mass for male rats sent into space is more than thepopulation mean red blood cell mass for male rats not sent into space.1.dWhich of the following is/are additional conditions required for the confidence interval to be valid?Select all required conditions.

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