Suppose the investigation produces a result that is statistically significant using both methods. What can be concluded if method i is used that cannot be concluded if method ii is used? Explain your answer.

We can conclude that we have a greater degree of diversity amongst the population in Method I in comparison with Method II

Explanation:

Method I employed the use of stratified random sampling. Stratified random sampling is a sampling method in which the population is partitioned into smaller categories based on common characteristics.

In Method I, participants were randomly selected from amongst those that volunteered and were then chosen either to exercise with a training partner or to exercise alone.

Method II employed the use of simple random sample. Simple random sample is a sampling method in which every individual is randomly selected with each individual having an equal chance or likelihood of being chosen.

In Method II, participants were randomly selected from a fitness center and were then queried to know whether they exercised with a training partner or they exercised alone.

In Method I, since stratified random sampling was used, there is a likelihood (a 50% likelihood) that a participant chosen could have his usual exercising routine changed. For example, a volunteer who usually exercised alone upon being selected at random could have his routine changed to training with a partner or a volunteer who usually exercised with a partner upon being selected at random could have his routine changed to training alone. This change in exercising routine would account for a greater change in targeted exercise intensity for each person who had his routine changed. As such, we have a greater degree of diversity in this method (Method I).

In Method II, because the participants used their usual exercising routine, the change in targeted exercise intensity for every person will not differ much. As such, we have a lesser degree of diversity amongst the population in Method II as compared to Method I.