# Probability and Statistics Terms

## Get down with the lingo

### Bar Graph

A representation of data that uses rectangular bars to show the magnitude of categorical variables. Useful in all sorts of real-life situations.### Bivariate Data

Data that deals with relationships between two variables. Talk about double trouble.### Box And Whisker Plot

A representation of data that displays the range and quartiles of the data set. Looks like a kitty cat when you squint and tilt your head to the left.### Categorical Data

Data that can be organized into mutually exclusive groups or categories.### Combination

One of all possible ways of choosing objects out of a larger group where order does not matter. Not Judge Judy's favorite math concept, that's for sure. The formula is .### Continuous Data

A type of data for which there's no separation between the possible values.### Correlation

The measure of the linear relationship between two variables. Can be positive or negative, depending on which side of the bed it woke up on.### Discrete Data

A type of data for which there's only a finite number of possible values. For example, the integers are discrete because there's no integer between 1 and 2, or between 2 and 3, etc. Also, they're*very*good at keeping secrets.

### Event

A set of outcomes of an experiment.### Factorial

The product of all the integers from*n*down to 1:

*n*! =

*n*× (

*n*– 1) × (

*n*– 2) . . . × 2 × 1. The most excited of all key terms.

### Graph

A diagram representing data or relationship(s) between variables.### Histogram

A representation of data that uses rectangular bars to show the magnitude of quantitative variables.### Independent Event

Events*A*and

*B*are independent if the outcome of event

*A*has no effect on the outcome of event

*B*. It's grown up! It can do what it wants!

### Interquartile Range

The difference between the third and the first quartile.### Linear Regression

Fitting a straight line to a set of data points to find the linear relationship between the dependent and independent variables.### Mean (Average)

The sum of all the data points divided by the number of data points.### Median

The middle value of a list of data points.### Mode

The data point with highest frequency.### Mutually Exclusive Event

Events*A*and

*B*are mutually exclusive if the occurrence of event

*A*implies event

*B*can't occur. They had a bad breakup last year, and they just refuse to be in the same room.

### Odds

The ratio of the probability that an event will happen to the probability that it will*not*happen.

### Outliers

Data points that are numerically far away from the rest of the data set. The loners of the group, if you will.### Permutation

One of all possible rearrangements of a collection of objects where the order of the objects is super important. To arrange*n*objects in

*r*ways, we use the formula .