Research Methods

• Independent Variable (IV): Variable the experimenter manipulates.
• Dependent Variable (DV): Variable the experimenter measures.
• Extraneous Variable: All variables that aren't the IV but can affect the results of the experiment if they aren't controlled.
• Aim: General statement about the purpose of an investigation.

  To see/ investigate/ understand.
• Hypothesis: A prediction of what will happen in a given situation. A precise testable statement about the expected outcome of an investigation.
• Null Hypothesis: The opposite of your hypothesis, which states there is no difference between groups/ conditions/ variables.
• Alternative Hypothesis: A prediction that there will be a difference/ effect/ relationship.
• Quantative Method: Using data that can be counted, usually numbers.
• Qualatative Method: Using data that is expressed as words and are non-numerical.
• Lab Experiment

  • An experiment that takes place in a controlled environment. Researcher changes the IV & measures the DV.
  • Strength: High level of control, especially over EV's. Can be more certain about cause and effect.
  • Weakness: Takes place in an artificial environment, may not be representative of real-life situations.
• Demand Characteristics: Participants find out the aim of the study and change their behaviour.
• Field Experiment

  • Takes place in a neutral environment. Researcher changes the IV.
  • Strength: Lower risk of participants changing their behaviour - demand characteristics.
  • Weakness: Raises ethical issues. If participants are unaware they're being studied, is it right to manipulate and record their behaviour.
• Natural Experiments

  • Conducted in everyday environments of participants. Experimenter has no control over IV- naturally occurs.
  • Strength: Allows research where IV can't be manipulated for ethical / practical reasons.
  • Weakness: A naturally occurring event may only happen very rarely, reducing opportunities for research. Less generalisable.
• Experimental Design: Refers to the condition/ groups of the experiment and how the participants take part in these condition groups.
• Experimental Group: A group where the participants in a research study are exposed to the manipulation of the IV.
• Control Group: Participants are not exposed to the manipulation of the IV. Responses are compared to those in the experimental group.
• Independent Groups Design

  • Different participants are used in each condition of the experiment.
  • Strength: Data-collection will be less time-consuming if all conditions of the experiment can be conducted simultaneously.
  • Weakness: Risk of individual differences affecting the results between conditions.
• Matched Pairs Design

  • Pairs of participants are matched in terms of key variables, such as age. One member of each pair then placed in experimental group and other member in the control group.
  • Strength: Groups are matched - reduced chance of individual differences.
  • Weakness: Different participants need to be recruited for each condition. Difficult and expensive.
• Repeated Measures Design

  • Same participants take part in each condition of the experiment.
  • Strength: Results not subject to individual difference, putting more confidence into cause and effect relationship.
  • Weakness: Risk of observing order effects.
• Order-Effects: Order of conditions can affect the results.
• Randomisation: A way of controlling for the effects of extraneous variables.

  Allocating participants to tasks should be left to chance as far as possible, to reduce the investigator's influence.
• Standardised Procedures: The process in which procedures used in research are kept the same.
• Counterbalancing: Used to reduce order effects when using a repeated measures design.

  Participants sample divided in half, one completing conditions in one order, other in opposite. Any order effects should be balanced with this.
• Sampling

  • Participants selected to take part in a study are called the sample. The sample is obtained from larger target population.
• Representative: We can generalise the behaviour from our sample to the target population.
• Sampling Bias: Difficult to get a truly representative sample, so researchers aim to remove as much sampling bias as possible.
• Random Sampling

  • All members of target population have equal chance of being selected. -> List of members of target population, all names assigned a number, sample generated through lottery method.
  • Strength: Reduction of investigation bias as there's no involvement from researcher.
  • Weakness: As participants are selected by chance the sample could be representative or very unrepresentative of all subgroups.
• Opportunity Sample

  • Researchers select anyone who is willing and available to take part in the study - ask whoever's around at the time.
  • Strength: Cost-effective and less time-consuming compared to other sampling methods.
  • Weakness: Type of person who volunteers to take part in a study might be more eager or interested in the topic - could lead to demand characteristics.
• Stratified Sampling

  • Sample reflects the proportions of people in certain subgroups within the target population. Participants who make up each subgroup are selected using random selection.
  • Strength: Most representative sampling method. Reduced bias.
  • Weakness: Time-consuming compared to other sampling methods.
  • Formula:
  • (Sample Size / Population Size) * Subgroup Size
• Systematic Sampling

  • Every nth member of the population are selected.
  • Strength: Reduction in investigator bias as there's little input from the researcher.
  • Weakness: All members of target population between nth element are ignored.
• Types of Data

  Primary: Refers to data that has been directly collected by the researcher, solely for the purpose of their investigation.

  • Strength: Researcher has control over the data, data collection can be designed specifically to the aim.
  • Weakness: Collecting primary data is lengthy and expensive.
• Types of Data

  Secondary: Information that someone else has collected.

  • Strength: Cheap to use, no need to set up data collection.
  • Weakness: Data might not exactly fit the needs of the study.
• Types of Data

  Meta-Analysis: Systematic review that involves identifying on aim and then searching for research studies that have addressed similar aims/ hypothesis.

  • Strength: Increases the validity of the conclusions drawn as they're based on a wider range.
  • Weakness: Research designs in studies can vary so they're not comparable.
• Ethical Issues in Psychology

  Deception: Purposely misleading participants. If participants haven't received the correct information about what they're taking part in, they have been deceived.

  Dealing with deception:

  • Debriefing: Participants should be made aware of the aims of the investigation and what the data is being used for.
  • Right to Withdraw: Withhold their data from the study or withdraw from the study completely.
• Ethical Issues in Psychology

  Informed Consent: Making participants aware of the aims of the research procedures, their rights and what their data will be used for.

  Dealing with informed consent:

  • Consent Letter: Contains all the information that the participants need to know. Participants sign if they agree to take part. If under 16, a parental signature is needed.
• Ethical Issues in Psychology

  Protection from Harm: Participants who are involved in research, should not be put in any more harm than their daily lives, and should be protected from psychological and physical harm.

  Dealing with protection from harm:

  • Debriefing: Participants should be made aware of the aims of the investigation and what the data is being used for.
  • Right to Withdraw: Withhold their data from the study or withdraw from the study completely.
• Ethical Issues in Psychology

  Privacy: Participants have the right to control information about themselves.

  Confidentiality: Information is not made publicly known.

  Dealing with privacy & confidential:

  • Protect Personal Data: Keep records of personal data protected.
  • Anonymity: Use pseudonyms or initials when mentioning specific participants
• Questionnaires: Written method of data collecting where participants record their own answers to a list of questions. Used to gather people's opinions and behavioural attitudes.
• Closed Questions: Researcher provides a range of possible answers. Best used for quantative data.
• Open Questions: Researcher doesn't restrict the range of possible answers. Best used for qualatative data.