methodology

• point :)

  a strength of this study is its use of controlled laboratory experiments
• example :)

  experimental research can demonstrate a causal relationship, e.g. by deliberately manipulating the independent variable (the verb used to describe the impact), we can see the causal effect on the dependent variable (estimate of speed) and draw a causal conclusion.
• explain :)

  in this controlled laboratory, L&P have control over all variables, ensuring that the data collected is accurate and true.
• link :)

  this increases the internal validity of L&P's experiments, as the tests measure what they intend to measure.
• point :(

  the sample was made up of university students only.
• explain :(

  the participants in the study were US college students only, meaning that they are all likely to share similar characteristics, e.g. lack of driving experience. This would reduce the validity of L&P's findings, as these young students may not be able to judge how fast a car is travelling. However, it could be argued that using other groups of people may be more prone to being affected by misleading questions.
• example :(

  Schacter et al. (1999) has found that compared to younger students, elderly people have difficulty remembering the source of their information, even though their memory for the information itself is unimpaired.
• link :(

  however, it could still be argued that L&P had researcher bias when choosing what group to make up their sample, therefore reducing the external validity of this research.