Variables, Falsifications & Operational Definitions in Psychology

Variables in Psychology

Definition of Variables: Something that varies, referring to behavior which is observable and replicable.
- Quantitative Variable: Varies by amount.
- Continuous: Measured on a scale (e.g., calories, time).
- Discrete: Measured in counts (e.g., pieces, segments).
- Qualitative Variable: Varies by class (e.g., labels such as SES, political affiliation, psychological traits).

Aims to describe, interpret, and explain behaviors or events through methods such as interviews and observations.
- Example: Participants may explain their anxiety, examining commonalities or distinctiveness.
- Case Study: Radesky et al. (2014) observed mobile device usage at the dinner table, concluding that:
- Phone use decreased caregiver responsiveness.
- Caregivers who were highly absorbed in their devices often reacted harshly to child misbehavior.

Decision Factors for Measurement:
1. Using established measures from prior research.
2. Modifying existing measures.
3. Refining constructs of interest.
Measurement Process: Assigning symbols to objects/events according to rules.

**Types of Scales:
1. Nominal Scale:
- No properties of real numbers; categories are arbitrary with no quantitative characteristics.
1. Ordinal Scale:
- Places events in rank order, but does not convey the distance between ranks.
- Special case includes a neutral center point (e.g., -3 to +3 scale for approval).
1. Interval Scale:
- Equal intervals between numbers, but lacks a true zero point (e.g., IQ tests).
1. Ratio Scale:
- Contains a true zero point, allowing for meaningful ratio statements (e.g., speed of problem-solving).
Comparison of Scales:
- Nominal reveals differences, Ordinal indicates direction, Interval allows for magnitude comparisons, and Ratio permits ratio analysis.

Definition: An operational definition translates abstract concepts into observable form.
- Examples:
- Hunger operationally defined as number of hours without food.
- Intelligence defined as an IQ test score.
- Essential for empirical study to ensure clarity and communication in research objectives.

Stress:
- Self-rating of worry/tension.
- Psychological measures through questionnaires/rating scales.
- Frequency of nervous habits (e.g., fidgeting).
- Physiological measures (e.g., GSR - Galvanic Skin Response, heart rate).
- Situational demand considerations (e.g., task difficulty).
Limitations:
- Operational definitions may exclude important aspects or include extraneous factors.

Studies using different operational definitions can lead to identical conclusions.
- Example: Kinsbourne’s study on eye and head turning in relation to cerebral lateralization suggests different cognitive processing based on lateralization.

Modalities:
1. Self-report Measures: Direct inquiries; may lack validity.
2. Physiological Measures: Based on biological responses; often require costly technology.
3. Behavioral Measures: Observational in nature, providing opportunities to select relevant behaviors for construct definition.
Sensitivity and Range Effects:
- Range Effect: Limited sensitivity in measurement.
- Ceiling Effect: Score clustering at high ranges limits value increment.
- Floor Effect: Score clustering at low ranges inhibits value decrement.

Non-experimental Method: Descriptive, lacking variable manipulation.
Experimental Method: Involves variable manipulation for causal statements.
Challenges in Experimental Research:
- Ethical considerations, potential participant variables impacting the manipulation, and the artificiality of experimental settings.

Correlational Method: Measures covariation between two variables without causation.
Third-Variable Problem: Unaccounted variables may influence measured relationships.
Example: Study by Jansson-Fröjmark & Lindblom (2008) indicating a bidirectional relationship among anxiety, depression, and insomnia.

Artifact: Non-natural features introduced accidentally.
Experimenter Bias: Outcomes affected by expectations of the experimenter, limited by techniques such as:
- Standardization of the experiment.
- Single-blind study (experimenter unaware of expected results).
- Double-blind study (both participant and experimenter unaware).

Demand Characteristics: Cues suggestive of the study's purpose influencing participant behavior.
Participant Reactivity: Modification of natural behavior due to knowledge of participation in the study.
Subject Roles: Types of roles include:
- Good subject role: Supporting hypotheses.
- Negativistic subject role: Acting contrarily to the hypothesis.
- Apprehensive subject role: Presenting positively.
- Faithful subject role: Adhering strictly to instructions.

Importance of reviewing previous literature for appropriate measurement methods over sensitivity concerns.

Proper referencing of figures and tables in text, ensuring captions are clear and complete.
Selection of graph type based on variables involved (e.g., histogram for one interval variable, scatterplot for interval dependent and independent variables, etc.).

Figures & Tables: Examples include effects of temperature on writing speed and comparisons of central tendency (mean, median, mode) for smokers versus non-smokers, providing insight into behavioral studies related to tobacco use.