In exercises that call for two-sample procedures, you may use either of the two approximations for the degrees of freedom that we have discussed: the value given by your software or the smaller of and . Be sure to state clearly which approximation you have used.
7.69 Why randomize?
A coworker suggested that you give the new hybrid computers to the next seven employees who need new computers and the standard laptop to the following seven. Explain why your randomized design is better.
7.69
There could be things that are similar about the next 7 employees who need new computers as well as the following 7, which could bias the results (like being from the same office or department).