Explain the concept of blinding in experiments.
Blinding minimizes bias by preventing subjects and/or researchers from knowing who receives which treatment. Double-blind is ideal.
Explain the concept of a completely randomized design.
Experimental units are assigned to treatments completely at random. It's the simplest design but not always the best.
Explain the concept of a randomized block design.
Treatments are assigned randomly within blocks. Blocking helps control for known variables by grouping similar units together first.
Explain the concept of a matched pairs design.
Subjects are matched in pairs, and each pair receives both treatments in a random order. Useful when subjects are naturally related.
Explain why experiments can establish causation.
Experiments establish causation because treatment is imposed, separating them from observational studies where variables are only observed.
Explain the importance of controlling confounding variables.
Controlling confounding variables ensures that the observed effect is truly due to the treatment and not some other factor.
What are the differences between single-blind and double-blind experiments?
Single-blind: Either subjects or researchers don't know treatment assignment. | Double-blind: Neither subjects nor researchers know treatment assignment.
What are the differences between a completely randomized design and a randomized block design?
Completely Randomized: Units assigned randomly to treatments. | Randomized Block: Units divided into blocks, then treatments assigned randomly within blocks.
What are the differences between explanatory and response variables?
Explanatory: Variable that is manipulated. | Response: Variable that is measured as an outcome.
What are the differences between control group and placebo?
Control Group: Group that receives no treatment or standard treatment. | Placebo: An inactive treatment that looks like the real one.
What are the differences between replication and control?
Replication: Repeating the experiment with multiple units. | Control: Minimizing the effects of confounding variables.
What is the definition of an experiment?
A research method where a treatment is imposed to observe its effect on a response.
What are experimental units?
The individuals or objects to which treatments are applied.
What are response variables?
The outcomes measured after applying treatments.
What are explanatory variables (factors)?
Variables manipulated to see their effect on the response. Levels of these variables are called treatments.
What is a confounding variable?
A variable related to both the explanatory and response variables, making it difficult to determine the true cause of the effect.
What is a control group?
A group that does not receive the treatment, used as a baseline.
What is random assignment?
Assigning treatments randomly to eliminate bias.
What is replication?
Repeating the experiment to ensure reliability.
What is a placebo?
An inactive treatment that looks like the real one.
What is the placebo effect?
When subjects respond favorably to any treatment, even a placebo.
