# Exploring Data Flashcards

What is a categorical varialbe?

variables that take on values that are names or labels, such as color, or breed of dog.

What is a quantitative variable?

variables that are that are numerical, and represent a measurable quantity, like salary or height.

How do we represent categorical variables?

With bar charts or pie charts

How do we represent quantitative variables?

With histograms, stem and leaf plots, or boxplots

When do we use the mean to describe a distribution?

When the distribution is unimodal and symmetric

When do we use the median to describe a distribution?

When the distribution is not unimodal and symeetric.

What is standard deviation?

The average distance from the mean

What is a z score?

The number of standard deviations away from the mean

What is percentile?

percent to the left

What is the five number summary?

min, Q1, median, Q3, max

What is IQR

interquartile range: Q3 - Q1

What is the empirical rule?

mean-68-95-99.7–yes!!

What percent of data lies above the median?

50%

How do you determine “outliers”

1.5 IQR’s above Q3 or below Q1

If a distribution is skewed right, which is higher, the median or mean?

the mean–the mean chases the tail!