A) To test his hypothesis that ballet training will improve both the fielding and batting performance of his players, how should the coach decide which players will take ballet training and which will not? Why should he choose to assign the players in this fashion?
B) Identify/describe the different levels of the independent variable.
The independent variable in this experiment is ballet training. As described above, there are only two levels (training and no training). However, there could be more levels if the coach assigned some players to only two weeks of training, some players to four weeks of training, and some others to six weeks of training.
C) Identify the dependent variables the coach should measure.
The dependent variables in this study are batting performance and fielding performance. Both of these variables could be measured in a variety of ways using data normally collected during baseball games. To measure batting performance, the coach could use batting average or slugging percentage. To measuring fielding performance, the coach could use each player’s number of errors for the season. There are probably some better advanced statistics for fielding performance, however.
D) Suggest a placebo treatment the coach could use to control for the influence of the Hawthorne effect. Which players will receive the placebo treatment?
The Hawthorne effect is the tendency of experimental participants to improve their performance because they are being studied. In this context, the Hawthorne effect would cause the players who took ballet training to improve their performance not because of the ballet, but because they are conscious of being studied. To prevent this problem from providing false support for the hypothesis, the coach should give a placebo treatment to the players who are not selected to participate in ballet. That way, all of the players will feel like they are being studied. The Hawthorne effect will be equivalently influential in the treatment and control groups. A good placebo treatment for this study might be meditation training. While some players are in ballet practice, the others should practice meditating. Future research would have to rule out the possibility that meditation improves baseball performance, however.