Vocab 1
Objects that are describe by a set of data maybe people, animals, or things
Individuals
A distribution is roughly __ if the right and left sides of the graph are approxi- mately mirror images of each other.
Symmetric
A distributed is skewed to the right if the right side of the graph (containing the half of the observations with larger values) is much longer than the left side. It is skewed to the left if the left side of the graph is much longer than the right side.
skewed distributions
The ___ s measures the average distance of the observations from their mean. tI is calculated by finding an average of the squared distances and then taking the square root. Thisaverage squared distance si caled the variance. nI symbols, the variance 2⁄3s is given by
The standard deviation
Any characteristic of an individual taking different values for different individuals
Variable
An association between two variables that holds for each individual value of a third vari- able can be changed or even reversed when the data for al values of the third variable are combined. This reversal is called ____
Simpson's paradox
T find the mean _ (pronounced "X-bar") of a set of observations, add their values
and divide by the number of observations. If the n observations are X1, X2, ..X.,, their mean is
The mean X
The thing of one of the categorical variables in a two-way table of counts is the distribution of values of that variable among all individuals described by the table.
Marginal distribution
A variable places an individual into one of several groups
Categorical variable
We say that there's __ between two variables fi specific values of one variable tend to occur in common with specific values of the other.
Association
The ___ M is the midpoint of a distribution, the number such that half the observations are smaller and the other half are larger.
median
Call an observation an outlier fi it fall’s more than 1.5 × IQR above the third quartile or below the first quartile.
The 1.5 X IQR rule for outliers
A variable that takes numeral values for which it makes sense to find an average
Quantitative variable
Distortion or asymmetry in normal distribution of data.
Skew
Describes how similar or varied the data is from a specific set of values. Includes range, quartiles, IQR, and standard deviation.
Spread
A thing of a variable describes the values of that variable among individuals who have a specific value of another variable. There is a separate conditional distribution foreach value of the other variable.
Conditional distribution
The thing of a variable tells us what values the variable takes and how often it takes these values.
Distribution
The overall look of the data when arranged on a table. Includes skew, spread, center and outliers.
Shape
The circle is then split into fractions and labeled depending on the data.
Pie chart
The _____ of a distribution consists of the smallest observation, the first quartile, the median, the third quartile, and the largest observation, written in order from smallest ot largest. In symbols, the five-number summary is
The five-number summary