Our results are similar to the original study in which there is insignificant difference in number of words recalled for both no rehearsal and highlighting group. However, small differences that I found from my results are that the mean number of words recalled is higher in the highlighting group and the mean differences between two groups are greater than the original study. This may because there was distractions going on in the middle of the original study’s experiment so this may affect the original results. For the procedure, there is a bit of changes in which we did not include a distractor task that supposed to be given before they were asked to recall the words so it would be difficult to suggest which method is more effective for recalling more words as it is unclear whether those words would stay in our memory after a while.
Moreover, my research supports the Atkinson ; Shiffrin’s theory in which in the highlighting method, participants got to repeat and pronounce the words subvocally more times that the non-rehearsal group’s participants therefore the number of words recalled in highlighting group is greater than the non-rehearsal group but the differences would not be significant because few amount of repetitions within a minute are not enough to transfer those words to LTM so those words would still be stored in STM that may only hold 7+2 amount of information and no longer than 30 seconds or even there is a possibility for the words to only enter the sensory memory then decay as paying equal attention to every word shown for 3 seconds is very difficult to do.
This experiment has its strengths such as during the standardized direction, the experimenters did not told its aim to the participants, therefore, demand characteristics may not establish so it won’t affect the results, but, after the experiment, they were debriefed for a while so they did not leave the laboratory with curiosity. Besides, they were also asked ‘Are there any questions?’ as the experimenter want to ensure that everyone are clear with the procedures so they won’t be confused anymore on what they should do. In both groups, the slides were shown exactly for 3 seconds and was prepared few days before, therefore it makes the results comparable and reduce the possible human errors that may happen on that day. Additionally, the experiment has high construct validity because in this case, memory was being measured by the number of words recalled from the list of 20 words, so an operationalised results may be obtained. Lastly, since the experiment is conducted in highly controlled environment therefore it has high internal validity which means the confounding variables that may exist is being minimised. Hence, the procedures tend to be replicable by other researchers which makes the results’ reliability able be verified.
Whereas, its limitations are since it was conducted in laboratory so its artificial situation causes it to has low ecological validity in which the results may not be generalized to natural settings as different outcome may be obtained. For the sample, since it consisted of unequal males and females high school students from a specific private Indonesian school, so it had low population validity in which the results may not represent the wider population of high school students of the entire cultures or schools. Besides, since the experiment was conducted during lunch time right after the lesson period so their concentration may be lost and distracted from factors such as tiring and hungry, therefore, this may lead them not to participate seriously. Also, the 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 and affect the results. The confounding variables that may exist and are not well-controlled are their intelligence on how fast they could memorize the 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 because experimenters could figure out the small problems that present and manipulate it before the actual experiment, therefore, an accurate results may be obtained and experimenter errors may be minimised. Additionally, the cross-cultural research of rehearsal method on memory would be worth investigated because we could know whether the method is always effective for groups of people of different cultures or not.
Overall, it can be concluded that the null hypothesis was supported in which there is no significant difference in the number of words recalled between participants who had rehearsal method of highlighting and no rehearsal method.