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