Experimental method Flashcards
Key features of the experimental method
1) Manipulation of an IV to know whether a second variable (DV) is changed
2) Control of extraneous variables
3) Random allocation of participants to the conditions
Examples of confounding variables and how they are overcome
ISSUE: Differences in instructions given by researcher or stimulus materials being used
RESOLVED: Standardised instructions and materials
ISSUE: Differences between participants (IE age)
RESOLVED: Use a single age group, or ensure age structure of each condition is similar
Alternative to random allocation?
Allow all participants to participate in both conditions (not always appropriate
Advantages of the experimental method
- Holds all variables but the IV constant, allowing the researcher to establish a cause and effect relationship between IV/DV (difficult to achieve with humans outside laboratory setting)
- Allows researchers to force the pace of the research rather than waiting for periodic or rare natural events. Control of when and where
- Possible to generalise findings to the population that was used in the test sample
Disadvantages of the experimental method
- Difficult to generalise findings beyond population. Populations may be male dominated, race dominant, they may all be volunteers
- Participants are mostly aware they are participating in an experiment, which may affect their behavior
- May not be possible to use (unethical)
Laboratory experiments
- Highest level of control over variables
- Setting does not indicate it is a laboratory setting! Observational research may occur in a laboratory
Advantages of laboratory experiments
Replicability: Well designed, clearly reported and therefore easy to reproduce which can make the findings stronger (more reliable)
Control over variables: Easiest way to control potential confounding variables so that a cause> effect (IV>DV) relationship can be established
Sophisticated equipment can be used for accurate results, which may be sensitive to external conditions
Disadvantages of laboratory experiments
Loss of validity: High control=artificial. Low ecological validity as setting is unusual
Demand characteristics: Participants adjust their behavior in light of the fact they are in an experiment. May guess the hypothesis, act in a way that is helpful to the researcher or give a ‘screw you’ response. Provoked by standardized procedure
Ecological validity
The extent to which findings may be generalised to settings other than the one in which the research took place
Lab-low ecological validity because it is an unusual setting
Demand characteristics
Participants try to make sense of the research situation they are in and adjust their behavior accordingly
Ethical issues of laboratory experiments
Consent: overwhelmed by their environment, participants may not feel able to withdraw from the procedure. Violates right to withdraw
Deception: Some lab experiments involve deception, particularly in social psychology. Debriefing about the nature of the study, the findings and permission to use them is essential
Animals: Used because they offer the researcher greater experimental control than with humans. However this makes them susceptible to unnecessary suffering as they are unable to give consent
Field experiments
Carried out in the natural environment of those being studied so realism is improved
*IV is still manipulated DO NOT CONFUSE WITH NATURAL
Advantages of field experiments
Improved ecological validity: natural real life setting, improvement on laboratory
Reduced demand characteristics: participants less conscious they are taking part in an experiment
Weaknesses of field experiments
Establishing controls: Difficult to control variables; both IV, DV and confounding. IE non participants talking in passing. Therefore less replicable
Generalising to other situations: High realism, but can’t be generalised from the setting where the research took place
More costly
More difficult to use sophisticated equipment that doesn’t function properly outside of the highly controlled laboratory environment
Ethical issues involving field experiments
Consent: Issues relating to informed consent and right to withdraw
Confidentiality: Real world settings, therefore identity of participants, or organisations must be protected. Participants must be warned when complete anonymity cannot be guaranteed
Use of animals: When animals are the subject of the experiment their natural environment is altered in some way
Natural experiments
Uses naturally occurring IV (no researcher control) Quasi experiment as no complete control. May be used after unforeseen events in environment permit study
Advantages of a natural experiment:
Reduction of demand characteristics: Less conscious they are taking part in experiment
Lack of direct intervention: Researcher doesn’t intervene so reduction of effect on participant’s behavior, though even their presence may still effect the results
Disadvantages of a natural experiment
Loss of control: No control of IV and no allocation of participants to conditions, therefore low degree of control and increased chance of confounding variables, meaning a certain cause>effect relationship may not be established
Replicability: Natural event that has opened possibility of research may not occur often
Ethical issues with a natural experiment
Consent: Issues arising from lack of informed consent and right to withdraw, similar to field experiment
Protection of participants: Research may cause unwarranted distress. Ie asking participants about their opinions on the death penalty in a period of increased murders/terrorist atrocities may cause distress
Confidentiality: Real world settings, therefore identity of participants, or organisations must be protected. Participants must be warned when complete anonymity cannot be guaranteed
Correlational analysis
- Measures the relationship between two variables. Value between +1 (perfect) and -1 (inverse perfect correlation) is recorded
- Correlational research measures the relationship between two variables
Advantages of Correlational analysis
Measure the strengths of a relationship, a precise numerical value is given, can be compared to other relationships
Value to exploratory research: Can be used to measure many variables/relationships between them. Therefore good tool for complex relationships
Weaknesses of Correlational analysis
Causality: Not possible to determine cause and effect, can only determine the degree of a relationship. Two variables may be linked but the cause could still be external to the relationship
Measurement of non linear relationships: Cannot be be measured by correlational means as no meaningful relationship is established (non linear means curved ect), so the relationship must instead be plotted
Ethical issues for Correlational analysis
Consent: Issues of informed consent and right to withdraw
Use of findings: Relationships may be established regarding sensitive subjects. Consent from participant is necessary for participation but also for the use of findings
Observational research
-Behavior is observed and recorded, no manipulation of variables. Emphasis on how people behave in certain situations. Can be used when intervention would be inappropriate (funeral) or unethical (with children)
The study setting for observational research
NATURALISTIC
- Often in natural setting of participant (naturalistic observation)
- Useful for when behavior would be difficult to measure in a laboratory
- Useful in study of non-human animals observed in natural habitat
- OBSERVATION IN A LABORATORY IS STILL SOMETIMES NATURALISTIC: One may assume behavior would be artificial and structured, but rats adapt well to laboratory settings so behavior may be natural enough for naturalistic observation. Further, laboratories may be made to look like playrooms (ie Strange Situation observation) where participants can be observed through a one way mirror- sufficiently natural for naturalistic
The role of the Researcher in observational research
Participant observation or non-participant observation (in the group or external), and should the observer be disclosed or remain undisclosed?
*Important ethical issues to consider about deception and consent
The structure of observation activity in observational research
- Unstructured: detailed verbal transcripts of behavior - suitable for when trying to establish the cause of said behavior
- Structured: Categorizing aspects of behavior, to determine the most common behaviors and how frequently they occur, quantitative data
Advantages of observational techniques
Preliminary research tool: Allows potential researcher to identify possible hypothesis for an experiment
Validity: Allows one to show or be shown that findings from laboratory research apply outside the lab in the real world. Realism + ecological validity are good so long as observer remains undisclosed
Weaknesses of observational techniques
Control: Level of control over confounding variables is poor, no cause and effect
Not easy to replicate due to differences in natural settings, not generalisable
Observer effects: Participants know they are being observed and change their behavior, and participant observers may be biased
Ecological validity lower in laboratory observation than naturalistic
Cost
Coding systems: Subjective categorization of findings. Aggression and ‘rough play’ may be different levels of behavior for different researchers - hard to compare
Ethical issues with observational techniques
Privacy: unless presumptive consent/consent is gathered, researchers should protect the psychological well being of the participants by only observing in an environment they would usually be expected to be observed in (by strangers)
Confidentiality/consent: If not observing in a place participants would expect to be observed they should gain consent to use the findings, debrief them and guarantee their anonymity/inform them anonymity cannot be guaranteed
Self Report techniques: questionnaires
- Participants provide information knowingly on information relative to themselves
- Series of questions on area of interest
- Systematic gathering of information from large population
- Carried out on generalisable sample
- Wide variety of suitable situations
Closed questions
- Researcher determines the range of possible answers
- Produce information easy to analyze, quantify (often numerical)
- May lack realism due to forced choice of responses (not every response will fit the pre selected categories
Open-ended questions
- Researcher does not restrict the range of possible answers
- Detailed, verbal information
- More difficult to analyse due to wide range of possible answers
Leading questions
-Choice of wording used suggests the respondent should reply in a particular way
Good practice when constructing a questionnaire
- small number of questions
- short questions
- clear phrasing
- avoid emotionally charged questions
- use a PILOT STUDY
Advantages of questionnaires
Simplicity- can be used with minimum training once properly developed. Closed question generated data is easy to analyse
Speed and cost- large amounts of questionnaires can be produced quickly and analyzed in the same fashion
Less influence of interpersonal variables - Researcher is not involved directly and cannot influence the response as much
Weaknesses of questionnaires
Ambiguous phrasing may lead to differing interpretations of a question
Leading questions
Different interpretations of language, ie rarely can mean once a month, or once a year (?)
Social desirability: participants do not answer truthfully so they are seen in the best possible light (true especially with embarrassing questions). Also researcher bias if given face to face
Poorly designed questionnaires produce poor data: questions that are hard to interpret or analyse, and those that do not give useful data, waste of time
Low response rate: many will not fill in the questionnaire, therefore not representative and only certain type of person will respond - not generalisable
Ethical issues with questionnaires
Privacy: Must treat information as private and must be published confidentially,protecting identity
Consent: Right to withdraw data from study
Risk of harm: Probing personal matters that may elicit stress response. Protect from harm by ensuring answers may not be given
Debriefing and support: Questions on a sensitive topic can be harmful, may require debriefing
Self report techniques: interviews
- Used both as basis of case study or survey
- Used face to face, or at distance
- Researcher communicates with the participant directly in a structured or unstructured manner
Structured interviews
Questions decided in advance to structure responses, usually produce quantitative data
- Less likely to deviate from topic, analysis is simpler, results easier to generalise, less training needed, and more objective so less interviewer bias
- However, can’t follow up new lines of enquiry and validity threatened as clients react to formality of the structured interview
Unstructured interviews
- Little decided in advance, broad questions as start point and then conversation takes its course
- More flexible and results more valid, as interviewee may say whatever is appropriate
- Harder to analyse data due to wide variety of possible answers, less generalisable and more training needed
Semi-structured interview
- Some prepared questions provided by interviewer supplemented by additional questions allowing the participant to expand
- Middle way between structured and unstructured
Focus groups in interviews
- Multiple individuals interviewed communally
- Gives greater understanding of group dynamic and social responses to different issues
- However may not be representative of the group’s view as individuals may dominate the session
Advantages of interviews
Flexible: explores complex issues, not possible with other techniques
Explores sensitive issues: Not as easy with indirect address
Different types of interview generate different types of data, and are appropriate for different situations, flexible
Weaknesses of interviews
- Interpreting data: subjective and difficult with unstructured interviews
- Time and effort: people may not be willing to give up time, limits number of possible people in sample
Limitations of interviewee responses: may not be able to properly articulate their responses
Interpersonal variables: sex and age may affect the correspondence between the interviewer and interviewee
Demand characteristics: social desirability bias
Cost
Need for training
Ethical issues with interviews
Respecting privacy
Consent: right to withdraw and consent to be interviewed
Protection from harm
Debriefing and support
Case studies
- In depth and long term study of individual case
- Real life context
- Representative case or exceptional circumstances
- Both numerical data and an account of events are produced
Advantages of case studies
Rich/interesting data: High degree of realism and can provide substantial detailed information into areas hard to investigate
Challenging existing theory: Findings may contradict existing evidence, leading to development of the theory
Weaknesses of case studies
Low reliability: Hard to replicate as rare or unethical
Subjective findings: Lengthy research means researcher develops relationship with the subject of the study, causing subjective interpretation of the findings
Selecting from large amounts of data: Large amounts of data collected, researcher must decide what to leave out (subjective)
Distortion: if the individual is required to recall historical events then they may be inaccurate in their recall (retrospective)
Ethical issues with case studies
- Level of intrusion for individual does not damage well being
- Similar to observational/interview
- ->consent
- -> right to withdraw
- -> protection from harm
- -> confidentiality
- -> debriefing
