# Chapter 1

## 29 terms · Mr. Rodriguez, Troy High

### Categorical Variable

Data that can be placed in groups

### Quantitative Variable

Data in numerical where "math" makes sense. The average is important.

### Distribution

All possible data values

### Dotplot

A graph where a dot represents one data value

### Stemplot

A graph where a stem is chosen and the leaves represent one data value

### Describing a graph

The 3 "S"s. Senter (center), shape, and spread. Or SOFA (spread, outlier, form, average)

### Outlier

A data value that falls outside the overall pattern of the other data values

### Histogram

A graph where rectangles represent groups of data values

### Symmetric

The right and left sides of a distribution are approximately the same

### Skewed

Either left or right. The skewness = where the tail is

### Timeplot

A graph where the x-axis represents time in a chronological order. these graphs show how y changes or repeats (trends)

### Mean

Arithmeetic average

50th percentile

25th percentile

75th percentile

### IQR

inter-quartile range. Q3-Q1

### Outlier

Any data value that is below Q1-(IQR)1.5 or above Q3+(IQR)1.5

### Boxplot

A graph where the 5-number summary is used with lines at the minimum, Q1, Median, Q3, and the maximum. the rectangle is made with Q1 and Q3 with a line at the median.

### Five-number summary

Minimum, Q1, median, Q3, and maximum

### Standard Deviation

the average distance a data value is from the mea s=√(1/(n-1))∑(x1-xaverage)squared

### Bimodal

Distributions with two modes

### Relative Frequency Histogram

uses adjacent bars to show the distribution of values in a quantitative variable where each bar represents the number of values falling in an interval (y-axis is a percent)

### Uniform

a distribution roughly flat in shape

### Mode

most frequent variable. a hump or high point in the shape of the distribution of a variable

### Multimodal

a distribution with 2 or more modes

### Unimodal

a distribution with 1 mode

### Percentile

the number that falls above a given % of data

### Range

difference between the maximum and the minimum value

### Variance

the square of the standard deviation