Practical cognitive

• Our aim was To partly replicate Peterson and Peterson’s research on Trigrams, to see if the number of repetitions of a trigram improves recall in short-term memory.
• our independent variable was Number of repeats of the trigram (3 letters) said out loud, either 1 or 3.
• our dependant variable was Number of correctly recalled  trigrams recalled out of min 0, max 3.
• Participant Design: Repeated measures, in one condition the participant was asked to repeat the trigram once aloud, whereas in the other they repeated the trigram three times before counting backwards.
• Sampling method was opportunity sampling We stated that the experiment was looking at memory to see how we process information to teachers who we knew within school and the venue would be in a classroom in school. 

   
• Our sample consisted of 10 male and female teachers of different subjects from our school. We had an equal split of male and female teachers with a range of ages.  Where in the UK was this taking place? How was it a 'lab' setting.
• Memory was measured as the number of totally correct trigrams remembered after 18s of a distractor task on a score of 0-3
• Participants recalled what they remembered at the end of the 18 seconds for each of the total 6 trials
• We scored whether they recalled the trigrams completely correct or not
• Mean, median, mode, and standard deviation were calculated for Conditions A (one repeat of trigram) and B (three repeats of the trigram) of the experiment
• A histogram was created from the data for Conditions A and B
• A Wilcoxon statistical test was conducted to determine if there was a difference in memory performance between Conditions A (one repeat of trigram) and B (three repeats of the trigram)
• To adhered to the ethical guidelines and gave the participants consent forms,  we stated that the experiment was looking at memory to see how we process information and that they had the right to withdraw during or after the experiment.  We kept all of our participants identity anonymous  After the experiment ended we gave our participants a debrief after about the true aim which was to see whether more repetitions would improve memory recall and gave them an email to withdraw their data if they wanted to after the session.
• To analyse our quantitive data we worked out the measures of central tendency for the two groups (repeated once) and (repeated twice). We found that the mean number of letters recalled was greater when the participants said the letters once compared to when they said the three letters once. 

   
• The standard deviation was also calculated which showed that there was very little individual differences in the conditions and between conditions because they were (1) and (1.14) out of a total score of 3 which shows that there was a very little dispersal of memory rating around the mean. For both groups of data the median was 2.
• Quantitative results show mean memory for one repetition is 2.14 compared with 2.0 with three or two repetitions but this was not a significant difference.

   
• What can you conclude from the raw data

  We were unable to replicate Peterson and Peterson’s research on Trigrams, and concluded that repetition of a trigram does not improve recall in short-term memory.

  This was shown in our results of mean memory for one repetition of  2.14 compared with 2.0 with three  repetitions out of a maximum of 3, but this was not a significant difference.

  n't have a significant effect on the number of total correct syllables recalled.
• Therefore, there is not a significant difference in memory recall for trigrams when ppts repeat the trigram once compared with three times prior to a distractor task.
• Procedure:

  Data collection

  We sent out an email using volunteer sampling, once they had shown interest we gave them a consent form which stated that they had the right to withdraw and ensured informed consent. They were called to a classroom and we read out standardised instructions. The ppts were asked to recall 3 random letters we had given to them after an interference task where they had to count back in 3’s from a set number for a measured time. We collected their answers, writing down the number of correct letters they got in each trial. After this we debriefed the ppts. 
• Procedure

  Data analysis

  Following totalling the number of syllables correctly recalled by each participant for each condition, we calculated the mode, median, mean range and standard deviation for the data. In addition to this, we also presented our data in graphical form allowing us to compare the scores from the two conditions of 1 or 3 repeats. Our findings can then be compared with the results of Peterson and Peterson (1959).

   
• Null hypothesis : there will be no significant difference between the number of repeats of the trigram said allowed (0 or 3) the number of correctly recalled trigrams (0-3)
• Experimental hypothesis: There will be a significant improvement in number of correctly recalled trigrams (0-3) for the 0 repeats condition versus three repeat of the trigram .