What is Statistics?
The science of collecting, analyzing, and drawing conclusions from data
Why Should one Study Statistics?
- To be informed
- To make informed judgement
- To evaluate decisions that affect your life
Variability
Is universal, allows us to distinguish between usual and unusual values
Population
The entire collection of individuals or objects about which information is desired
Census
Preformed to gather information about the entire population
Sample
A subset of the population, selected for study in some prescribed manner.
Descriptive Statistics
The method of organizing and summarizing data
Inferential Statistics
Involves making generalizations from a sample to a population
Variable
Any characteristic whose value may change from individual or object to another.
Data
The values for a variable from individual observations
Categorical Variables
Qualitative; identifies basic differentiating characteristics of the population
Numerical Variables
Quantitative; Observations or measurements take on numerical values
Discrete
Isolated points along a number line; usually counts of items
Continuous
Variable that can be any value in a given interval, usually measurements of something
Univariate
Data that describes a single characteristics of the population
Bivariate
Data that describes two characteristics of the population
Multivariate
Data that describes more than two characteristics of the population
When to use a Bar Graph?
Categorical data
When do use a Dotplot?
Small numerical data sets
