In a flight simulation test, a particular pilot among a grou…

In a flight simulation test, a particular pilot among a group of pilots receives a very low score. However, when he takes the test after six months, he performs considerably better and his scores are closer to the average of the group. Which of the following is most likely to account for the higher scores?

Promelute Inc., a pharmaceutical company, conducts a study f…

Promelute Inc., a pharmaceutical company, conducts a study for its new drug for the treatment of obsessive-compulsive disorder. The researcher is unclear about the results of the study because he is not sure if the improvement observed resulted from the properties of the drug or from the participants’ expectations about the effect of the drug. Such an effect is known as a(n)________ effect.