Algebra 2 Honors TEST

Mean

the average of a set of scores, obtained by adding the scores and then dividing by the number of scores

Median

the middle score in a distribution; half the scores are above it and half are below it

Mode

The value that occurs most frequently in a given data set.

Standard Deviation

A measure of the variability of a data set

Sample

a subset of the population

Population

The collection of all data that are of interest

Parameter

a numerical description of a population characteristic

Statistic

a numerical measurement describing some characteristic of a sample

Hypothesis

A claim about a characteristic of a population

controlled experiment

experiment in which only one variable is changed

control group

the group that does not receive the experimental treatment.

treatment group

the group that receives the treatment

randomized comparative experiment

An experiment where subjects are randomly assigned to the control group or the treatment group

Placebo

A harmless, fake treatment that is similar to the actual treatment

normal distribution

A function that represents the distribution of variables as a symmetrical bell-shaped graph.

random sample

a sample that fairly represents a population because each member has an equal chance of inclusion

self-selected sample

members of a population can volunteer to be in the sample

systematic sample

a rule is used to select members of the population

stratified sample

The populations is divided into smaller groups that share a similar characteristic and then a sample is randomly selected from each group

cluster sample

A population is divided into groups. All of the members in one or more of the clusters are selected to be part of the sample.

convenience sample

only members of the population who are easily accessible are selected

experiment

A method of collecting data that imposes a treatment on individuals in order to collect data on their response to the treatment

observational study

A method of collecting data that observes individuals and measures variables of interest but does not attempt to influence the responses

survey

the collection of data by having people answer a series of questions

simulation

uses a model to reproduce the conditions of a situation or process so that the simulated outcomes closely match the real-world outcomes

margin of error

the maximum expected difference between a sample result and the population parameter it is estimating