Experiment Design

Front

What is an explanatory variable (EV)?

Back

An explanatory variable (EV) is a variable that is manipulated or controlled in an experiment to observe its effect on a response variable.

Front

What is the purpose of randomization in experiments?

Back

Randomization helps reduce the effects of confounding variables, ensuring that the results are more reliable and valid.

Front

What are lurking variables?

Back

Lurking variables are variables that are not included in the study but can affect the outcome, potentially confounding the results.

Front

Define nonresponse in the context of surveys.

Back

Nonresponse occurs when individuals chosen for a sample cannot be contacted or refuse to participate, leading to potential bias in the results.

Front

What is a completely randomized design?

Back

A completely randomized design is an experimental design where subjects are randomly assigned to different treatment groups without any restrictions.

Front

What is a confounding variable?

Back

A confounding variable is an outside influence that changes the effect of a dependent and independent variable, leading to erroneous conclusions.

Front

Explain the concept of bias in experiments.

Back

Bias refers to systematic errors that can affect the validity of the results, often due to the way the sample is selected or how data is collected.

Front

What is the difference between a placebo and an active treatment?

Back

A placebo is a treatment with no therapeutic effect, used as a control in experiments, while an active treatment is a substance or intervention that is intended to have an effect.

Front

What is the role of a control group in an experiment?

Back

A control group serves as a baseline to compare the effects of the treatment, helping to isolate the impact of the independent variable.

Front

Define stratified sampling.

Back

Stratified sampling is a method of sampling that involves dividing the population into subgroups (strata) and taking a sample from each stratum.