T-tests

In looking at your business, when and why would you want to use a one-sample mean test (either z or t) or a two-sample t-test? Create a null and alternate hypothesis for one of these issues. How would you use the results? A t-test is when the test statistic follows a t-distribution, and want to statistically test whether the null hypothesis is true. T-tests are used to test if the difference of means is statistically significant. It tests if the sample is representative of the populations. For example, if the mean for variable 1 is 20 and the mean for variable 2 is 28, we may say the means are different. T-tests may show that they are not significantly different, however, and we can't base our conclusion on the means' difference since the difference in the sample is not...