STAT 1000 FINAL EXAM QUESTIONS AND
100% CORRECT ANSWERS!!
What are the graphical displays for categorical data?
pie charts, bar graphs, etc
What are the graphical displays for quantitative data?
histogram, stemplot, box plot, etc
Stemplots
separate each observation into a stem and a leaf that are then plotted to display the distribution
while maintaining the original values of the variable
histograms
show the distribution of a quantitative variable by using bars whose height represents the number
of individuals who take on a value within a particular class
Stemplots vs Histograms
Stemplots: Appropriate for small data sets, display the actual values of the observations
Histogram: Appropriate for relatively large data sets, do not display the actual values of the
observations
Modes
Modes are major peaks of a distribution
Unimodal
one peak
Bimodal
two peaks
Multimodal
distributions with more than two modes
, What does "skewed to the right" mean?
means that the tail end is pointing to the right
What does "skewed to the left" mean?
means that the tail end is pointing to the left
How are mean and median different?
▶ The mean is sensitive to the influence of extreme observations. We say that it is not a
resistant measure of the center.
▶ The median is more resistant than the mean.
▶ The mean and median of a roughly symmetric distribution are close together.
▶ In a skewed distribution, the mean is usually farther out in the long tail than is the median
Quartiles
Values that divide a data set into four equal parts
How do you calculate Q1?
The first quartile, Q1, is the median of the observations located tothe left of the median in the
ordered list
How do you calculate Q3?
The third quartile, Q3, is the median of the observations located tothe right of the median in the
ordered list
What is the five-number summary?
The five-number summary 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 to
largest.
(Minimun, Q1, M, Q3, Maximum)
boxplot
A graph of the five-number summary.
100% CORRECT ANSWERS!!
What are the graphical displays for categorical data?
pie charts, bar graphs, etc
What are the graphical displays for quantitative data?
histogram, stemplot, box plot, etc
Stemplots
separate each observation into a stem and a leaf that are then plotted to display the distribution
while maintaining the original values of the variable
histograms
show the distribution of a quantitative variable by using bars whose height represents the number
of individuals who take on a value within a particular class
Stemplots vs Histograms
Stemplots: Appropriate for small data sets, display the actual values of the observations
Histogram: Appropriate for relatively large data sets, do not display the actual values of the
observations
Modes
Modes are major peaks of a distribution
Unimodal
one peak
Bimodal
two peaks
Multimodal
distributions with more than two modes
, What does "skewed to the right" mean?
means that the tail end is pointing to the right
What does "skewed to the left" mean?
means that the tail end is pointing to the left
How are mean and median different?
▶ The mean is sensitive to the influence of extreme observations. We say that it is not a
resistant measure of the center.
▶ The median is more resistant than the mean.
▶ The mean and median of a roughly symmetric distribution are close together.
▶ In a skewed distribution, the mean is usually farther out in the long tail than is the median
Quartiles
Values that divide a data set into four equal parts
How do you calculate Q1?
The first quartile, Q1, is the median of the observations located tothe left of the median in the
ordered list
How do you calculate Q3?
The third quartile, Q3, is the median of the observations located tothe right of the median in the
ordered list
What is the five-number summary?
The five-number summary 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 to
largest.
(Minimun, Q1, M, Q3, Maximum)
boxplot
A graph of the five-number summary.
