The purpose of the study was to compare the mean salivary flow rate among subjects with cerebral palsy and among
The purpose of the study was to compare the mean salivary flow rate among subjects with cerebral palsy and among subjects in a control group. Each group had 10 subjects.
The following table gives the mean flow rate in ml/minute as Well as the standard error of the estimate of the mean. Here are some descriptive statistics of the salivary flow rate for each group.
![234_1.png](https://secure.tutorsglobe.com/CMSImages/234_1.png)
(a) Below we have comparative boxplots and overlayed normal probability plots for the salivary flow rate. Is it reasonable to assume that the populations are normal?
![581_2.png](https://secure.tutorsglobe.com/CMSImages/581_2.png)
Is it reasonable to assume that the population variances are equal? (Discuss)
(b) Do we have significant evidence at a = 5% that the mean salivary flow rate are different between these groups?
(c) Give a 95% confidence interval for the difference in mean salivary flow between these two group.