Psychology paper 2

• Experiment


  An investigation looking for a causal relationship in which an independent variable is manipulated and is expected to be responsible for changes in the dependent variable
• Independent variable


  The factor under investigation in an experiment which is manipulated to create two or more conditions (levels) and is expected to be responsible for changes in the dependent variable
• Dependent variable


  The factor in an experiment which is measured and is expected to be change under the influence of the independent variable
• Extraneous variable


  A variable which either acts randomly, affecting the DV in all levels of the IV or systematically, i.e. on one level of the IV (called a confounding variable) so can obscure the effect of the IV, making the results difficult to interpret
• Experimental condition


  One or more of the situations in an experiment which represent different levels of the IV and are compared for compared to a control condition
• Control condition


  A level of the IV in an experiment from which the IV is absent. It is compared to one or more experimental conditions
• Laboratory experiment


  A research method in which there is an IV, a DV and strict controls. It looks for a causal relationship and is conducted in a setting that is not in the usual environment for the participants with regard to the behaviour they are performing
• Independent measures design


  An experimental design in which a different group of participants is used for each level of the IV
• Repeated measures design


  An experimental design in which each participant performs in every level of the IV
• Matched pair design


  An experimental design in which participants are arranged in two pairs. Each pair is similar in waves that are important to the study and one member of each pair performs in a different level of the IV
• Demand characteristics


  Features of the experimental situation which give away the aims. They can cause participants to try to change their behaviour, e.g. to match their beliefs about what is supposed to happen, which reduces the validity of the study
• Random allocation


  A way to reduce the effect of confounding variables such as individual differences. Participants are put in each level of the IV such that each person has an equal chance of being in any condition
• Order effects


  Practice and fatigue effects are the consequences of participating in a study more than once, e.g. in a repeated measures design. They cause changes in performance between conditions that are not due to the IV, so can obscure the effect on the DV
• Practice effect


  A situation where participants' performance improves because they experience the experimental task more than once, e.g. due to familiarity or learning the task
• Fatigue effect


  A situation where participants' performance declines because they have experienced an experimental task more than once, e.g. due to boredom or tiredness
• Participant variables


  Individual differences between participants (such as age, personality, and intelligence) that could affect their behaviour in a study. They could hide or exaggerate differences between levels of the IV
• Counterbalancing


  Counterbalancing is used to overcome order effects in a repeated measures design. Each possible order of levels of the IV is performed by a different sub-group of participants. This can be described as an ABBA design, as half of participants do condition A then B, and half do B then A
• Standardization


  Keeping the procedure for each participant in an experiment exactly the same to ensure that any differences between participants or conditions are due to the variable under investigation rather than differences in the way they were treated
• Reliability


  The extent to which a procedure, task, or measure is consistent, for example, that it would produce the same results with the same people on each occasion
• Validity


  The extent to which the researcher is testing what they claim to be testing
• Field experiment


  An investigation looking for a causal relationship in which an independent variable is manipulated and is expected to be responsible for changes in the dependent variable. It is conducted in the normal environment for the participants for the behavior being investigated
• Generalize


  Apply the findings of a study more widely, for example to other settings and populations
• Ecological validity


  The extent to which the findings of research in one situation would generalise to other situations. This is influenced by whether the situation (e.g. a laboratory) represents the real world effectively and whether the task is relevant to real life (has mundane realism)
• Natural experiment


  An investigation looking for a causal relationship in which the independent variable cannot be directly manipulated by the experimenter. Instead, they study the effect of an existing difference or change. Since the researcher cannot manipulate the levels of the IV, it is not a true experiment
• Uncontrolled variable


  A confounding variable that may not have been identified and eliminated in an experiment, which can confuse the results. It may be a feature of the participants or the situation
• Self-report


  A research method, such as a questionnaire or interview, which obtains data by asking participants to provide information about them
• Questionnaire


  A research method that uses written questions
• Closed questions


  Questionnaire, interview, or test items that produce quantitative data. They have only a few, stated alternative responses and no opportunity to expand on answers
• Open questions


  Questionnaire, interview, or test items that produce qualitative data. Participants give full and detailed answers in their own words like no categories or choices are given
• Interrater reliability


  The extent to which two researchers interpreting qualitative responses in a questionnaire will produce the same records from the raw data
• Social desirability bias


  Trying to present oneself in the best light by determining what a test is asking
• Filer questions


  Items put into a questionnaire, interview, or test to disguise the aim of the study by hiding the important questions among irrelevant ones so that participants are less likely to alter their behavior by working out the aims
• Interview


  A research method used in verbal questions asked directly like face-to-face or on the telephone
• Structured interview


  An interview with questions in a fixed order which may be scripted. Consistency might also be required for the interviewer's posture, voice, etc. so they are standardized
• Unstructured interview


  An interview in which most questions depend on the respondent's answers. A list of topics may be given to the interviewer
• Semistructured interview


  An interview with a fixed list of open and closed questions. The interviewer can add more questions if necessary
• Subjectivity


  A personal viewpoint which may be biased by one's feelings, beliefs, or experiences, so may differ between individual researchers. It is not independent of the situation
• Objectivity


  An unbiased external viewpoint that is not affected by an individual's feelings, beliefs, or experiences, so should be consistent between different researchers
• Naturalistic observation


  A study conducted by watching the participant's behavior in their normal environment without interference from the researchers in either the social or physical environment
• Controlled observation


  A study conducted by watching the participant's behavior in a situation in which the social or physical environment has been manipulated by the researchers. It can be conducted in either the participant's normal environment or in an artificial situation