ap stats chapter 1

individuals

objects that are described by a set of data

variable

any characteristic of an individual

categorical variable

a variable that can place an individual into a group/category

quantitative variable

a variable that takes a numerical value that it would make sense to find the average of

discrete random variable

quantitative variable that takes a fixed set of possible values with gaps between them (pants size)

continuous random variable

quantitative variable that can take any value in an interval on the number line (waist size)

distribution

values/categories that the variable takes and how often it takes these values

marginal relative frequency

the percent or proportion of individuals that have a specific value for one categorical variable

joint relative frequency

the percent or proportion of individuals that have a specific value for one categorical variable and a specific value for another categorical variable

conditional relative fequency

the percent or proportion of individuals that have a specific value for one categorical variable among individuals who share the same value of another categorical variable

skewed left

the left half of the data is much longer on a graph than the right half

skewed right

the right half of the data is much longer on a graph than the left half.

describing the center of a distribution

median or mean

describing the spread of a distribution

range, IQR, or standard deviation