Evaluation - Hasset

• Strengths

  1. Ethical guidelines on treating lab animals were followed by researchers when caring for the monkeys. They had constant access to water, they were fed monkey chow twice a day, and fruits and vegetables every day.
• Strengths

  Using the operationalised behavioural checklist increased the validity and reliability of results, as it guided researchers on how to record observations in the same way. For example, the behaviour ‘sit on’ was described as sitting on or part of a toy.
• Strengths

  Different pairs of toys were used on each trial, and this increased the validity as we can determine that males were drawn to wheeled toys in general, and not just a specific wheeled toy.
• Strengths

  Using video cameras increased the validity of the data recorded because the monkeys were used to the cameras. If a researcher recorded data in person instead, the monkeys might show demand characteristics by playing more or less with the toys.
• Strengths

  Quantitative data collected on toy interaction duration allowed for the objective calculations of the average time the monkeys spent with the toys. This removes room for subjective interpretations.
• Weaknesses

  The standardised procedure was abandoned for a trial because a monkey tore a plush toy causing the trial to be stopped 7 minutes early. This reduces the reliability of results.
• Weaknesses

  There is a chance observer bias may have increased subjectivity. The researchers who analysed the tapes were familiar with the monkeys and their gender and this could have led them to unintentionally code the behaviour of the monkeys differently to their actual behaviour.
• weaknesses

  There was a lack of adult males in the sample, hence reducing the generalisability of results. The only one high-ranking male didn’t interact with any toys, hence, findings can only be generalised to lower-ranking, non-adult male monkeys.
• Weaknesses

  Ecological validity is low because the sample consisted of monkeys in captivity, and they might be more likely to show interest in new objects in their environment. Therefore, we can’t entirely generalise results to explain if wild monkeys behave in the same way.
• Weaknesses

  Validity is low because, in each trial, a group of monkeys were sent out. So if one monkey occupied the wheeled toy, another monkey wanting to play with a toy would go to the plush toy regardless of their personal preference.