Selection Bias Is a Threat to Internal Validity Arising from Failure

question 112

Multiple Choice

Selection bias is a threat to internal validity arising from failure to use

• A) a control group.
• B) counterbalancing across conditions.
• C) reliable measuring instruments.
• D) random assignment.

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Definitions:

Nonexcludable Problem

An issue characteristic of public goods, where it is not possible to prevent individuals who do not pay from consuming a good or service.

Optimal Level

The most favorable or efficient level of output or activity under given conditions, maximizing benefits or minimizing costs.

Public Good

A good that is non-excludable and non-rivalrous, meaning it can be used by everyone and one person's use does not diminish another's.

Free-rider Problem

A situation where individuals consume a good without contributing to its cost, typically in the context of public goods.