College Stats Vocab Quiz 2

Observational Study

A study that involves observing and measuring characteristics of interest in a part of a population.

Experiment

A study where a treatment is applied to a part of a population, known as the treatment group, and responses are observed.

Experimental Units

The groups in an experiment, including a control group (given a placebo) and a treatment group (given the treatment).

Confounding Variables

Factors that prevent an experiment from distinguishing the effects of different variables on a response.

Placebo Effect

A phenomenon where a subject responds positively to a placebo, believing it to be a real treatment.

Blinding

A method where subjects are unaware of whether they receive the real treatment or a placebo, aimed at reducing the placebo effect.

Double-Blind

A study design where neither the subjects nor the experimenters know who receives the placebo and who receives the real treatment.

Randomization

The process of randomly assigning subjects to different treatment groups to eliminate bias.

Completely Randomized Design

A design where subjects are assigned to treatment groups through random selection without any restrictions.

Randomized Block Design

A design that involves dividing subjects into blocks based on similar characteristics and then randomly assigning them to treatment groups within each block.

Matched Pairs Design

A design where subjects are paired based on similarities, with one receiving the treatment and the other receiving a placebo.

Sample Size

The number of subjects included in a sample, which is crucial for the validity of the study.

Replication

The process of repeating an experiment to verify results.

Census

A complete count or measurement of an entire population, which is often impractical.

Sampling

The process of counting or measuring a part of a population, which is more common and feasible than a census.

Random Sample

A sample where every member of the population has an equal chance of being selected.

Simple Random Sampling

A sampling method where every possible sample of the same size has an equal chance of being selected.

Stratified Sampling

A sampling method that divides the population into groups (strata) and selects random samples from each group.

Cluster Sampling

A sampling method that divides the population into clusters and selects all members from one or more clusters, but not all.

Systematic Sampling

A sampling method where every Kth member of the population is selected.

Convenience Sampling

A sampling method that selects members of the population that are easy to access, often leading to biased results.