Unit 3 Ap Stats Review FLASHCARDS

• Experimental units can be identified by who is being applied to the treatments and who is being measured from.

  Matched pair design means two things that are similar.

  Statistically Significant-observe a difference that is so large that you can rule out chance variation that it is not a coincidence

  1. P-value- value of observing the difference less than 5%, then it is statistically significant

  Bias- The result you are seeing is overestimating or underestimating the actual true value and being done systematically.

• Volunteer Bias- people choose to respond normally to people who feel very strongly about it

• Nonresponse Bias- People choose to not respond the survey so you don’t know about that group and how the people feel then the ones that did respond.

• Undercoverage Bias- part of the population is excluded from the sample

• Wording Bias- When the survey wording is leading to the response

  4 Key Experimental Principles

• Control, Replication (meant to rule out chance variation), Random assignment, Comparison

Simple Random Sample - every group of size n has the chance of being selected

Stratified Random Sample- more specific results, break them into strata(like gender or age ), similar purpose as a randomized block design

Cluster- All from some of the groups, spread out over a large area and look at everything in that group.

Systematic random sample- Randomly pick each person 1-20 start with the 4 one and then go to the 8 and continue on.

Population- the entire group of individuals that you hope to get results from

Sample- A representative subset of a population that is being examined in hope of learning about the population

Observational Study- Researchers do not assign treatments but they rather observe them or certain outcomes are measured.

Voluntary response sample- the researchers puts out a request for members of a population and they decide whether they want to be part of the sample

Convenience Sample - The researcher chooses a sample that is readily available in some nonrandom way like people walking on the street and getting polled.

Experimental Study- A treatment is intentionally introduced and result or outcome is observed.

Control- The group is an experiment that does not receive any treatment or manipulation.

Random Assignment- Placing participants into different treatment groups using randomization.

Factors- Variables in the study that we believe will influence the results

Levels- a measure or a scale to distinguish between measured variables that have different properties.

Treatments- The process, intervention that is applied to each subject in an experiment.

Completely randomized Design-Experimental units are randomly assigned to treatments equally by chance.

Randomized Block Design- Subjects or experimental units are grouped into blocks with different treatments and to be tested randomly in the units in each block.

Blinding- The participants can’t know which group they are sorted into

Single Blind- When the subjects in an experiment do not know if they are in the treatment or control group

Double Blind- When the subjects as well as the researcher do not know which subjects are in the treatments or control groups

Placebo- A fake treatment that is given to the control group to help prevent the placebo effect

Placebo effect- When a person appears to improve after taking a placebo.

Inference- Using data to make conclusions about a larger population.

Random Selection- Simple random sample is obtained by randomly selecting individuals from a target population.