Experimental Design and Threats to Validity in Research Quiz

Regression to the mean refers to the tendency of extreme scores to move toward the average, but it is not a threat to internal validity in research.

A control group establishes a baseline for comparison, helping researchers assess the impact of the independent variable.

Pretest sensitization occurs when participants' responses are influenced by knowledge of a pretest, posing a threat to internal validity.

A placebo group helps researchers assess the specific effects of the treatment by providing a baseline for comparison with the experimental group.

A pilot study assesses the reliability and feasibility of the experimental procedure before conducting the full-scale study.

Selection bias occurs when participants are not randomly assigned, leading to unequal groups and compromising internal validity.

The Hawthorne effect, where participants alter their behavior due to awareness of being observed, is a threat to external validity as it may not generalize to real-world settings.

The placebo effect occurs when participants experience improvement based on the belief that they are receiving a beneficial treatment.

Crossover design minimizes carryover effects and individual differences by exposing each participant to multiple conditions in a randomized order.

Blinding prevents bias by keeping both researchers and participants unaware of the experimental conditions, enhancing the study's internal validity.

Sampling bias, where the sample is not representative of the population, can compromise the external validity of study findings.

Randomization helps ensure that confounding variables are equally distributed among groups, enhancing the internal validity of the study.

Descriptive design is not an experimental design; it involves observing and describing phenomena rather than manipulating variables.

Regression to the mean is not a threat to construct validity, as it pertains to the stability of scores over time and does not affect the validity of a measurement.

Counterbalancing helps control for order effects by varying the order in which conditions are presented to participants.

History involves external events during the study that may impact the dependent variable, posing a threat to internal validity.

Random sampling bias is not a recognized type of bias; random sampling aims to reduce bias and ensure representativeness.