Question

A researcher conducts two studies. Each study was a one-sample z test. Both studies placed the rejection region in both tails and measured the same sample mean. The beat level in Study 1 was larger than the beta level used in Study 2. Which study is associated with greater power to detect an effect

Answer 1

Study 2 will produce a greater power to detect an effect because it has a lower beta level

Explanation:

Generally, alpha level is the probability of rejecting the null hypothesis when it's true. Whereas beta level is the opposite and it's the probability of accepting the null hypothesis even though it’s false.

Now, in statistics the lower the alpha level, the more we require a stronger evidence. Thus, a higher alpha level is usually required to produce a stronger evidence.

Now, an increase in alpha level means a decrease in beta level and a decrease in alpha level means an increase in beta level.

This means that the lower the beta level, the greater is the power to detect an effect.

Now, we are told that the beta level in study 1 was larger than the beta level used in Study 2.

Thus, study 2 will produce a greater power to detect an effect because it has a lower beta level