This experiment has its strengths such as during the standardized direction, the experimenters did not told its aim to the participants which means demand characteristics may not establish, therefore, results won’t be affected. Besides, they were asked ‘Are there any questions?’ before experiment begins as the experimenters want to make sure they are clear so confusion on what they should do during the experiment may be eliminated, which may lead to an accurate results obtained. In both groups, the slides were projected exactly for 3 seconds as it has been timed and was prepared few days before, therefore it makes the results comparable and decrease the possible human errors that may happen on that day. Additionally, the experiment has high construct validity because memory was measured operationalised by number of words recalled therefore valid results may be gained. Lastly, since the experiment was conducted in highly controlled environment, therefore, it has high internal validity which means confounding variables that should exist was being minimised. Hence, others researchers may able to verify the results’ reliability by replicate its procedures.
Whilst, the limitations are it has low ecological validity as it was conducted in laboratory that has artificial situation so results may not be generalised to natural settings as different results may be shown in that settings. For the sample, since it consisted of unequal males and females of high school students from specific school so it has low population validity in which results may not represent wider population of high school students of entire cultures or schools. Besides, this experiment was conducted during lunch time so their concentration may be distracted from factors such as tired or hungry which causes they not take it seriously and therefore influence the results. Also, participants were seated next to each other in U shaped classroom so it may be difficult for some to see the slides and stop talking after the experimenter asked them to be silence, so this may disturb others’ concentration which lead them not able to perform well. The confounding variables that might exist in this experiment are their intelligence on how fast they could study those words and the ignorance on still writing down words after they were asked to stop, so this could cause inaccurate results on the number of words recalled.
For future experiment, I would suggest to use another measurement of memory such as recalling songs’ lyrics or slang words instead of just recalling from a list of words as it may show different results. Also, it would be better to conduct pilot study beforehand because experimenters could figure out tiny problems that present and manipulate it before the actual experiment so that errors from experimenters may be minimised and more accurate results may be acquired. Lastly, cross-cultural research of rehearsal method on memory would be worth investigated because by doing this, it could show whether or not these method are always effective for groups of people in different cultures.