Ch 3
In a data set, the 25th percentile, or equivalently, the
First quartile
Quartiles divide the data into _____ equal parts
Four
Generally, the _______ is the best measure of central location when outliers are present
Median
In the neighborhood there are five houses listed for sale for the following amounts: $250,000, $275,000, $280,000, $295,000, and $515,000. What is the best measure of central location for the price of a house in the neighborhood?
Median
The measure of central location that can best be labeled as the midpoint of the data set is the
Median
The measure of central location where half the values of the data set lie above this measure and half the values of the data set by below this measure is known as the
Median
The arithmetic mean is usually not a good measure of central location is a ________ exists
Outlier
Extremely small or large values, also referred to as
Outliers
The mean is usually greater than the median when the data are ________ skewed
Positively
Match these quartiles with their percentiles
Q1 ——-> 25th percentile Q2——-> 50th percentile Q3———> 75th percentile Q4———-> 100th percentile
The function to find the mean of a subset in excel is
AVERAGEIF
The term _________ _______ relates to the way data tend to cluster around some middle or central value
Central location
The pth Percentile divides a variable into two parts. What percentage is greater than P?
(100-p)
In order to calculate the arithmetic mean, one
Add all of the data points, then divides by the number of data points
The pth percentile divides a variable into two parts. What percentage is less than the pth percentile?
Approximately P percent
The _______ is not considered a good measure of dispersion because it focuses solely on the extreme values and ignores every other observation in the sample or the population
Range
The _______ measures the difference between the largest and smallest values in a data set
Range
The function to find the mean of a subset an R is
TApply
Which of the following values is included in a box plot?
The first quartile
Which of the following values is included in a box plot
The second quartile
The formula for the weighted mean is x=EwiXi
They must sum to one
The modes usefulness as a measure of central location tends to diminish with variables that have more than ________ modes
Three
True or false: the main is the most widely used measure of central location for quantitative data
True
Which of the following is not a measure of central location
Variance
The mode is defined as
most frequently occurring value in the data set
