Chapter 1 -5: Statistics

Inferential statistics

Inferential statistics uses methods that take a result from a sample, extended it to the population, and measure the reliability of the result.

qualitative

qualitative, or categorical, variables allow for classification of individuals based on some attribute or characteristic

quantitative variables

quantitative variables provide numerical measures of individuals. The values of a quantitative variable can be added or subtracted, and provide meaningful results.

data

the list of observed values for a variable

variables

variable are the characteristics of the individuals within the population

continuous variable

a continuous variable is a quantitative variable that has an infinite number of possible values that are not countable. a continuous variable may take on every possible value between any two values.

discrete variable

a discrete variable is a quantitative variable that has either a finite number of possible values or a countable number of possible values. The term countable means that the values result from counting, such as 0,1,2,3 and so on. A discrete variable cannot take on every possible value between any two possible values.

parameter

a parameter is a numerical summary of a population

continuous data

are observations corresponding to a continuous variable.

discrete data

are observations corresponding to a discrete variable

quantitative data

are observations corresponding to a quantitative variable

qualitative data

are observations corresponding to qualitative variable

Statistic

A numerical summary of a sample

Individual

A person or object that is a member of the population being studied.

Sample

A subset of the population that is being studied

Descriptive statistics

Descriptive statistics consists of organizing and summarizing data. Descriptive statistics describe data through numerical summaries, tables, and graphs.

Statistics

Statistics is the science of collecting, organizing, summarizing, and analyzing information to draw conclusions or answer questions. In addition, statistics is about providing a measure of confidence in any conclusions.

Population

The entire group of individuals to be studied