The 3rd Variable Problem Flashcards

Study Notes

3rd Variable Problem & Causal Claims

A third variable refers to an additional factor that can influence the relationship between two studied variables, potentially confounding the results.
Causal claims assert that one variable directly causes a change in another variable, establishing a cause-and-effect relationship.

Identifying Causal Claims

Key phrases indicating causal claims include "causes," "influences," and "affects."
Tentative language such as "may" and "suggest" often accompanies causal claims, indicating uncertainty.

Graphical Representation

The independent variable (IV) is represented on the horizontal axis of a graph.
The dependent variable (DV) is represented on the vertical axis.

Understanding Variables

The independent variable is referred to as the cause in an experiment.
The dependent variable is identified as the effect resulting from the cause.

Covariance Concept

Covariance indicates that changes in the IV result in corresponding changes in the DV.
For example, in a study on popcorn consumption, increased container size leads to increased popcorn consumption.

Criteria for Establishing Causation

Three criteria must be met for establishing causation:
- Covariance: There must be a demonstrated correlation between IV and DV.
- Temporal sequence: The IV must precede the DV in time.
- Internal validity: The study must rule out alternative explanations for changes in the DV.

Temporal Sequence Clarification

The independent variable must occur before measuring the dependent variable; for instance, participants are given different sizes of popcorn containers prior to consumption measurement.

Importance of Internal Validity

Internal validity ensures that alternative explanations for changes in the DV are eliminated.
In an example study, controlling for the movie content ensures that it does not skew results related to eating behavior.

Goals of Scientific Research

Science aims to achieve various objectives:
- Understanding and describing phenomena leads to frequency claims.
- Making predictions pertains to association claims.
- Explaining phenomena is tied to establishing causal claims.

Description

This quiz focuses on the 3rd variable problem that can influence the relationships between two factors in research. It includes definitions of key terms such as causal claims and important keywords to identify causal relationships. Ideal for students brushing up on statistics and research methodology.