The process of scientific research in psychology 4

Basics of Research Methods (PSYB19-104)

Zsolt Horváth, PhD - horvath.zsolt@ppk.elte.hu

Planning Research

• Important preliminary steps in conducting psychological research.

Key Concepts in Research Methodology

Variables

• Definition: Phenomena/concepts that change and are measurable.

• Characteristics measured can include:

  • Psychological phenomena (e.g., anxiety, extroversion).

  • Characteristics with two or more categories or values.

  • Variability can exist:

    • Within an individual over time.

    • Between different individuals.

• Examples of variables:

  • Height, feelings towards others, attitudes, anxiety.

Example Distribution of Heights

• Graphical representation showing variability among individuals.

• Individual differences illustrated by data points (e.g., Alice, Bob, Charlie).

Quantifying Variables

• Categorical vs. Measured Variables:

  • Categorical: Non-numerical, distinct categories (e.g., marital status).

  • Measured: Numerical values on a scale (e.g., level of anxiety).

• Preference for measured variables over categorical ones in psychological assessment.

Measuring Variables

• Ease of measurement varies:

  • Easy: Height, weight, age.

  • Difficult: Personality traits, feelings.

• Quantification assigns numeric values but may lack information on qualitative differences.

Operational Definitions

• Importance of precise definitions for psychological constructs (e.g., defining aggression).

• Differences in measurement procedures can affect clarity and consistency.

• Example: Measurement of aggression through behavior observation and questionnaires.

Study Methodologies

Naturalistic Observation

• Method for observing and categorizing behavior in natural settings, such as playgrounds.

• Example from bullying research involving systematic observation criteria.

Sampling in Research

• Population vs. Sample:

  • Population: The entire group of interest.

  • Sample: A selected subset for study, providing insights that can be generalized.

• Bias in sampling can affect research outcomes, emphasizing the need for representative samples.

Causality in Research

• Importance of establishing cause and effect relationships.

• Confounding variables can lead to misinterpretation of data (e.g., variables that influence both A and B).

Types of Studies

• Cross-sectional Studies: Measure various variables simultaneously, unable to determine causality.

• Longitudinal Studies: Measure variables over time to assess stability, change, and causality.

• Randomized Experiments: Manipulate independent variables and control confounding factors to infer causality.

Reliability and Validity in Measurement

• Reliability: Consistency of a measurement instrument over time.

• Validity: Accuracy in measuring what it intends to measure; requirements may differ drastically in psychology.

Hypotheses in Research

• Role of hypotheses in defining expected relationships between variables.

• Types of hypotheses:

  • Causal Hypotheses: Indicate a cause-effect scenario.

  • Non-causal Hypotheses: Indicate only an association.

• Directional vs. Non-directional hypotheses:

  • Directional: Predict the nature of the relationship.

  • Non-directional: Indicate simply that a relationship may exist.

Final Notes

Importance of Research Design

• Research design impacts the interpretation of data and the reliability of conclusions drawn.

• Effective research planning incorporates previous research, hypotheses formulation, and clearly defined aims to elucidate findings.

Statistical Analysis

• Involves hypothesis testing (null vs. alternative), types of testing (one-tailed vs. two-tailed), and understanding relationships through correlation and covariance.