Business Statistics Chapter 2
percent frequency distrivution
summarizes the percent frequency for the data of each class
crosstabulation
tabular summary of data for two variables
class midpoint
the value halfway between the lower and upper class limits
relative frequency distribution
gives a tabular summary of data showing the relative frequency for each class.
stem and leaf display
graphical display used to show simultaneously the rank order and shape of a distribution table
data visualization
graphical displays to summarize and present information about a data set.
pie chart
also presents relative frequency and percent frequency distributions for categorical data.
approximate class width formula
approximate class width= (largest data value- smallest data value)/ number of classes
relative frequency formula
relative frequency of a class= frequency of the class/ n
simpson's paradox
reversal of conclusions based on aggregate and unaggregated data
displays used to show relationships
scatter diagram trendline
dot plot
shows detail of data and how many at each time.
cumulative percent frequency distribution
shows the percentage of data items with values less than or equal to the upper limit of each class.
cumulative relative frequency distribution
shows the proportion of data items
displays for comparison
side by side chart stacked bar charts
bar chart
a graphical display for depicting categorical data summarized in a frequency, relative frequency, or percent frequency distribution.
what does cumulative frequency distribution show?
the number of data items with values less than or equal to the upper class limit of each class.
How to define class for a frequency distribution with quantitative data?
1. Determine the number of nonoverlapping classes 2. determine the width of each class 3. determine the class limits
what does the sum of relative frequencies always equal?
1.00
histogram
a graphical display of a frequency distribution, relative frequency distribution, or percent frequency distribution of quantitative data constructed by placing the class intervals on the horizontal axis and the frequencies, relative frequencies, or percentage frequencies on the vertical axis.
scatter diagram
a graphical display of the relationship between two quantitative variables
data dash board
a set of visual displays that organizes and presents information used to monitor performance of a company or organization in a matter that is easy to read, understand, and interpret.
frequency distribution
a tabular summary of data showing the number (frequency) of observations in each of several nonoverlapping categories or classes.
cumulative frequency distribution
a variation of frequency distribution that provides another tabular summary of qualitative data.
stacked bar chart
bar chart in which each bar is broken into rectangular segments of a different color showing the relative frequency of each class in a manner similar to a pie chart.
displays used to show distribution of data
bar chart, pie chart, dot plot, histogram, stem and leaf display
relative frequency of class formula
frequency of class/ n
side-by-side bar chart
graphical display for depicting categorical data summarized in a frequency, relative frequency, or percent frequency distribution.
upper class limit
identifies the largest possible data value assigned to the class
lower class limit
identifies the smallest possible data value assigned to the class
trendline
line that provides an approximation of the relationship
