Ch 6: Research Design and Causation

Association

A criterion for establishing a nomothetic causal relationship between two variables. Variation in one variable is related to variation in another variable.

Causal Effect (Idiographic Perspective)

When a series of concrete events, thoughts, or actions results in a particular event or individual outcome.

Causal Effect (Nomothetic Perspective)

When variation in one phenomenon, an independent variable, leads to or results, on average, in variation in another phenomenon, the dependent variable.

Ceteris Paribus

Latin phrase meaning “other things being equal.”

Cohort

Individuals or groups with a common starting point. Examples include college class of 1997, people who graduated from high school in the 1980s, General Motors employees who started work between the years 1990 and 2000, and people who were born in the late 1940s or the 1950s (the baby boom generation) or between 1981 and 1996 (millenials).

Context

A set of interrelated circumstances that alters a relationship between other variables or social processes.

Contextual Effect

A variation in relationships of dependent with independent variables between geographic units or other social settings.

Counterfactual

The situation that would have occurred if the subjects who were exposed to the treatment were not exposed but otherwise had had identical experiences to those they underwent during the experiment.

Cross-Sectional Research Design

A study in which data are collected at only one point in time.

Ecological Fallacy

An error in reasoning in which incorrect conclusions about individual-level processes are drawn from group-level data.

Emergence

The appearance of phenomena at a group level that cannot be explained by the properties of individuals within the group; emergence implies phenomena that are more than “the sum of their parts.”

Event-Based Design (Cohort Study)

A type of longitudinal study in which data are collected at two or more points in time from individuals in a cohort.

Extraneous Variable

A variable that influences both the independent and dependent variables, creating a spurious association between them that disappears when the extraneous variable is controlled.

Fixed-Sample Panel Design (Panel Study)

A type of longitudinal study in which data are collected from the same individuals at two or more points in time. In another type of panel design, panel members who leave are replaced with new members.

Idiographic Causal Explanation

An explanation that identifies the concrete, individual sequence of events, thoughts, or actions that resulted in a particular outcome for a particular individual or that led to a particular event; may be termed an individualist or historicist explanation.

Longitudinal Research Design

A study in which data are collected that can be ordered in time; also defined as research in which data are collected at two or more points in time.

Mechanism

A discernible process that creates a causal connection between two variables.

Mediator

A variable involved in a causal mechanism (intervening variable).

Moderator

A variable that identifies a context for the effect of other variables.

Nomothetic Causal Explanation

An explanation that identifies common influences on cases or events.

Nonspuriousness

A criterion for establishing a causal relation between two variables; when a relationship between two variables is not caused by variation in a third variable.

Random Assignment

A procedure by which each experimental subject or group is placed in a condition randomly.

Randomization

The random assignment of cases, as by the toss of a coin.

Reductionist Fallacy (Reductionism)

An error in reasoning that occurs when incorrect conclusions about group-level processes are based on individual-level data; also known as an individualist fallacy.

Repeated Cross-Sectional Design (Trend Study)

A type of longitudinal study in which data are collected at two or more points in time from different samples of the same population.

Spurious Relationship

A relationship between two variables that is caused by variation in a third variable.

Statistical Control

A method in which one variable is held constant so that the relationship between two (or more) other variables can be assessed without the influence of variation in the control variable.

Subject Fatigue

Problems caused by panel members growing weary of repeated interviews and dropping out of a study or becoming so used to answering the standard questions in the survey that they start giving stock or thoughtless answers.

Time Order

A criterion for establishing a causal relation between two variables; the variation in the presumed cause (the independent variable) must occur before the variation in the presumed effect (the dependent variable).

Units of Analysis

The level of social life on which a research question is focused, such as individuals, groups, towns, or nations.

Units of Observation

The cases about which measures actually are obtained in a sample.