FSCI 5353 Lecture 7: Intro to Experimental Design Part 2

Flashcards about Experimental Design

What is Quasi-Experiment?

An experiment to a certain degree. Used when randomization is not possible, resulting in less control over validity.

What should you do in quasi-experimental design when you cannot randomize?

Use nonequivalent groups designs and make groups as comparable as possible by matching subjects using important variables related to the DV under study.

What is Factorial Design used for?

To determine the necessary amount of treatment using two or more experimental groups.

What is validity in experimental designs?

The extent to which a metric in an experiment actually measures the concept it purports to measure.

What is internal validity?

The ability of an experimental design to document the causal relationship between an IV and a DV.

Define causality in the context of internal validity.

Application of X directly caused the impact on A to become B.

What are some threats to internal validity?

History, maturation, testing, regression, experimental mortality/attrition, instrumentation, and selection bias.

What is experimental mortality/attrition?

Subjects dropping out prior to completion of the experiment for various reasons.

What is instrumentation threat to internal validity?

Changes in the measurement process (e.g., instrument isn't used the same way in successive measurements).

What is selection bias?

The way in which subjects are chosen (i.e., not randomly).

What is generalizability?

Quality of a research finding that justifies the inference it represents something more than the specific observations on which it was based.

What is external validity?

Whether the results from experiments in one setting will be obtained in other settings.

What is a threat to external validity??

Reactivity: An awareness that they are being measured causes a change in the behavior of subjects.

What is statistical conclusion validity?

Whether we are able to determine if two variables are related.

What are the benefits of experimental research?

Ability to isolate the effect of an IV on a DV, ability to measure how much of an effect a treatment has on an outcome, and ability to demonstrate causality.

What are the limitations of experimental research?

Requirement of much time, money, control, potential for serious ethical concerns, and possible lack of feasibility.

What is the relationship between internal and external validity?

Internal validity must be established before external validity is an issue