validity

Validity in Psychological Research

Validity: The extent to which an observed effect in psychological research is genuine, meaning it accurately measures what it was intended to measure. Also, it assesses if results can be generalized beyond the research setting in which they were found.

Face Validity: A basic form of validity where a measure appears, at face value, to assess what it claims to measure. For example, a test designed to evaluate anxiety should intuitively appear to measure anxiety.
Concurrent Validity: The degree to which a psychological measure correlates with an already established measure. High concurrent validity is indicated if the correlation between the two sets of data exceeds +0.80.
Ecological Validity: The extent to which research findings can be generalized to real-world settings and situations outside of the study environment. It focuses on how results apply to everyday life.
Temporal Validity: The degree to which findings from a study can be generalized across different historical periods or eras. It questions whether conclusions drawn from the study hold true over time.

Validity addresses whether a study accurately represents the truth and the extent to which results can be applied to other contexts. Reliable measurements that do not measure accurately lack validity (e.g., consistent but incorrect weight readings from a miscalibrated scale would lack validity in measuring actual weight).

Internal Validity: Assesses if observed effects in an experiment are a result of the manipulation of the independent variable, rather than other factors (e.g., participant bias).
- Example: In Milgram's study, internal validity was questioned since participants might have acted per perceived expectations rather than genuine reactions.
External Validity: Refers to the ability to generalize findings from the study to other contexts, populations, and times.
- Ecological Validity is a subset of external validity focused more on generalizing findings to everyday life situations.

Achieved by visually checking the measure for its perceived effectiveness or by having it evaluated by experts.

Achieved by administering a new test alongside a well-established test and comparing scores. A correlation exceeding +0.80 indicates good concurrent validity.

Control Groups: Using control groups allows the researcher to better assess whether changes in the dependent variable are truly due to the independent variable.
Standardising Procedures: Minimizes participant reactivity and investigator effects, enhancing validity.
Single-Blind Procedure: Participants are unaware of the study's aims to reduce demand characteristics.
Double-Blind Procedure: Both participants and the researcher are unaware of key aspects of the study to minimize biases.

Ensuring anonymity encourages honest responses, thus enhancing ecological validity. Incorporation of lie scales helps detect inconsistencies in responses, controlling for potential biases.

Observations that include minimal researcher intervention often produce high ecological validity, especially if the observer remains undetected, allowing for more authentic behavior to be measured.
Low mundane realism can negatively affect ecological validity (e.g., using a non-natural task to assess real-world behavior).

Questions whether study findings are relevant in different time periods (e.g., critiques of conformity findings from studies based in the 1950s assert they may not apply to present social norms or behaviors).
Quotes from historical figures, like those from Freud, may reflect outdated societal views and attitudes, diminishing their temporal validity.

Qualitative methods, such as interviews and case studies, often possess higher ecological validity due to their depth and detail that reflect participant realities. However, researchers must still establish the interpretive validity, ensuring the interpretations align with participants' perspectives.
Triangulation: The use of multiple data sources (e.g., interviews, diaries, observations) adds credibility and supports validity.

Nuisance Variable: Any unsolicited variable that could affect the dependent variable, not systematically related to the independent variable.
Systematic Variable: Any variable affecting the dependent variable that is systematically related to the independent variable.
Demand Characteristics: Cues that lead participants to guess the study's purpose, affecting their behavior.
Investigator Effects: Researcher behavior impacting the outcome, including study design and interaction with participants.
Leading Questions: Wording in questions that implies a particular answer and may influence participant responses.

A psychologist develops a questionnaire with 20 questions to evaluate belief in ghosts.
1. Describe what validity means in this context (3 marks).
2. Identify two methods to improve the investigation's validity (4 marks).