Research method, individual and the group (Experiment)

When writing about research methods, the following concepts should be explained:

Experiment: A research method in which the researcher manipulates an independent variable and measures its effect on a dependent variable under controlled conditions on participants who have been randomly allocated to conditions.

Quasi-experiment: The researcher manipulates an independent variable and measures its effect on a dependent variable, but participants are not randomly allocated to conditions; they are assigned to conditions based on pre-existing traits.

Natural experiment: The researcher uses a pre-test /post-test design but does not manipulate the independent variable.  The IV is naturally occurring. Participants are also not randomly allocated to groups.

Naturalistic observation: An naturalistic observation does not manipulate an independent variable, but observes the behaviour of a participant in their natural environment.  The observation may be overt - where the participants are aware they are being observed - or covert.

Abrams et al

Aim: Abrams

conducted a study to determine if in-group identity would affect one's willingness to conform. It also looks at the role of SIT on the level of conformity.

Procedure: The students were given a stimulus line to compare with three other lines of different lengths, one of which is the same length as the stimulus line. The student's task is to identify which of the three lines is the same length as the stimulus line. A ' naive' student will be introduced to an in-group to be psychology students or an out-group to be history students. The students will be seated in a row to give their judgement on the lines, everytime the 'naive' student will be placed at the end of the row so that they'll be the last to give their answer.

Findings: Seventy-seven per cent of all participants conformed to the erroneous confederate judgments on at least one trial. The actual proportion of conforming responses was 138 out of a possible 432 (i.e. 32 per cent). This is very similar to the results of the original Asch experiments.

Strengths:

  1. Experiment can be easily replicated
  2. It showed the effect of a group on conformity
  3. Experiment was repeated to ensure reliability

Limitations:

  1. the experiment used an artificial task to measure conformity which cannot be generalized to other real life situation
  2. Set in an unnatural environment which made the study lack ecological validity

Hamilton and Gifford

Aim: To investigate illusory correlation of group size and negative behaviour.

Procedure:Researchers asked participants to read descriptions about two made-up groups (Group A) and (Group B). Group A and Group B; A twice as big as B (26 vs 13); same ratio of good behaviour to bad behaviour in both groups (positive twice as common as negative) \n Descriptions were based on a number of positive and negative behaviours. \n Group A (majority group) - twice as many members than B; performed 18 positive and 8 negative behaviours. \n Group B (minority) - performed 9 positive and 4 negative behaviours. \n Participants were then asked how many of the people in each group had positive vs. negative traits.

Findings:They overestimated the number of negative traits in the minority group. Although there was no correlation between group membership and the types of behaviours exhibited by the groups, in that the proportion of negative and positive was the same for both groups, the participants did seem to have an illusory correlation. \n More of the undesirable behaviours were attributed to the minority Group B, than the majority of Group A.

Strengths: replicable and reliable, cause and effect can be established.

Limitations: low ecological validity

When evaluating or discussing research methods, you may consider the following points:

  • Only true experiments can determine a causal relationship.  All other research methods show a correlational relationship. However, consistent findings of correlation also provide evidence that there may be a causal relationship.
  • Research done under controlled conditions is necessary to determine causality; however, psychological research is the balance between ecological and internal validity.
  • Research methods may obtain quantitative, qualitative data, or both.  Each type of data has different strengths and limitations.
  • Quantitative research allows for statistical testing to determine the significance of the data.  However, measuring behavior with quantifiable data is often seen as a reductionist approach.  Qualitative data is more holistic in its approach but is more difficult to analyze. Instead of a statement of significance, psychologists write an interpretation of the data.
  • The more standardized the procedure of a research study, the easier it is to replicate.  This is important to establish the reliability of the findings.
  • Researcher bias is an important consideration when carrying out research.  Blind controls are often used in order to increase the objectivity of the research.