Transcript ch03xt

Guide to Using Excel For Basic
Statistical Applications
To Accompany
Business Statistics: A Decision Making
Approach, 6th Ed.
Chapter 3:
Describing Data Using Numerical
Measures
By
Groebner, Shannon, Fry, & Smith
Prentice-Hall Publishing Company
Copyright, 2005
Chapter 3 Excel
Examples
 Population
Mean Foster City Hotel
 Mean, Median,and ModeWeigh-In-Motion
 Percentiles and Quartiles
Weigh-In-Motion
More Examples
Chapter 3 Excel Examples (continued)
Measures of Variation Weigh-In-Motion
 Empirical Rule Burger N’ Brew

Population Mean
Foster City Hotel
Issue:
Determine the mean nightly revenue for
the Foster City Hotel.
Objective:
Use Excel to calculate the population
mean revenue Data File is FosterCity.xls
Population Mean – Foster City Hotel
Open the Excel file called
FosterCity.xls
Population Mean – Foster City Hotel
Option 1 – Use the Excel
Average function.
Click the function wizard –
Select Statistical category –
Select Average
Population Mean – Foster City Hotel
Specify data range Click OK
Population Mean – Foster City Hotel
Population Mean
Population Mean – Foster City Hotel
Optional Method:
Select Tools, then
Data Analysis
Population Mean – Foster City Hotel
Select Descriptive
Statistics
Population Mean – Foster City Hotel
Define Data Range
and select options
Population Mean – Foster City Hotel
Mean Revenue
Mean, Median and ModeWeigh-In-Motion
Issue:
Does the WIM scale produce gross
weights that are close to the POE weights?
Objective:
Use Excel to develop histograms for the
weights from each scale and to compute the
mean, median, and mode for each scale. The
data file is Trucks.xls.
Mean, Median, and Mode- Weigh-In-Motion
Open the data
file called
Trucks.xls
Data File contains
200 trucks. Last
row is 201
Mean, Median, and Mode- Weigh-In-Motion
Constructing histograms
was covered in Chapter 2
(See Capital Credit Union)
here is an optional method
for determining the
frequency distribution and
histogram using Pivot
Tables
Mean, Median, and Mode- Weigh-In-Motion
Group the WIM weights by
10,000 pounds starting at
15,000 pounds (See Capital
Credit Union example in
Chapter 2 for specific steps
required to group data.
Mean, Median, and Mode- Weigh-In-Motion
Highlight the frequencies
and click on the Chart
Wizard to develop “quickand dirty” histogram
Mean, Median, and Mode- Weigh-In-Motion
Close Gaps by selecting
bars – Right Clicking –
select Format Data Series then Options.
Mean, Median, and Mode- Weigh-In-Motion
Completed Histogram for
WIM gross weights – Repeat
the process for POE gross
weights. Then compute
mean, median and modes
for both variables
Mean, Median, and Mode- Weigh-In-Motion
Select Tools – then select
Data Analysis
Mean, Median, and Mode- Weigh-In-Motion
Click on Descriptive
Statistics
Mean, Median, and Mode- Weigh-In-Motion
Define Data Range
and select options
Mean, Median, and Mode- Weigh-In-Motion
Delete un-needed columns
Mean, Median, and Mode- Weigh-In-Motion
Mean, Median, and Mode
Percentiles and QuartilesWeigh-In-Motion
Issue:
Determine Percentiles and Quartiles for
WIM and POE Gross Weights
Objective:
Use Excel to calculate 10th percentiles and
1st and 3rd quartiles for weigh-in-motion data.
Data file is Trucks.xls
Percentiles and Quartiles – Weigh-In-Motion
Open the data
file called
Trucks.xls
Data File contains
200 trucks. Last
row is 201
Percentiles and Quartiles – Weigh-In-Motion
Select function
wizard –
Statistical –
then Percentile
Percentiles and Quartiles – Weigh-In-Motion
Enter Data Range
and desired
percentile
Percentiles and Quartiles – Weigh-In-Motion
WIM Percentile
Results – Process
also repeated for
POE
Percentiles and Quartiles – Weigh-In-Motion
Select Chart Wizard
– click on Statistical
– then select
Quartiles
Percentiles and Quartiles – Weigh-In-Motion
Enter Data Range
and desired quartile
Percentiles and Quartiles – Weigh-In-Motion
1st and 3rd quartiles
for WIM and POE
gross weights
Measures of Variation Weigh-In-Motion
Issue:
Understand the Variation in POE and WIM
gross Weights
Objective:
Use the Excel to compute various
measures of variation in WIM and POE Gross
Weights Data file is Trucks.xls
Measures of Variation – Weigh –In-Motion
Open the data
file called
Trucks.xls
Data File contains
200 trucks. Last
row is 201
Measures of Variation – Weigh –In-Motion
Click on Tools tab – then select
Data Analysis – then choose
Descriptive Statistics
Measures of Variation – Weigh –In-Motion
Define data range, output
location – request
Summary Statistics
Measures of Variation – Weigh –In-Motion
Standard Deviation,
Variance, and Range
Measures of Variation – Weigh –In-Motion
For POE, select Tools –
Data Analysis –
Descriptive Statistics
Define data range, output
location – request
Summary Statistics
Measures of Variation – Weigh –In-Motion
Standard Deviation,
Variance, and Range
Empirical Rule Burger N’ Brew
Issue:
Analyze the Phoenix Burger Sales
Distribution
Objective:
Use the Excel to compute graphs and
numerical measures necessary for using the
empirical rule to analyze sales at Burger N’ Brew
Data file is BurgerNBrew.xls
Empirical Rule – Burger N’ Brew
Open the data file
called
BurgerNBrew.xls
Data File contains
sales for 365 days.
Last row is 366.
Empirical Rule – Burger N’ Brew
First, develop
histogram – class
width = 2. Form
Bins (upper limit
of each class)
Refer to Example 2-6 for detailed
steps in developing the
histogram
Empirical Rule – Burger N’ Brew
Click on Tools tab – then Data
Analysis – then Histogram
Empirical Rule – Burger N’ Brew
Define input
range, bin
range, output
location –
check Chart
Output
Empirical Rule – Burger N’ Brew
Excel default output – See Capital
Credit Union example Chapter 2 for
specific steps to enhance the
histogram – close gaps, label , etc.
Empirical Rule – Burger N’ Brew
Finished Histogram – Bell Shaped
Distribution
Empirical Rule – Burger N’ Brew
To compute numerical measures –
Click Tools – Data Analysis –
Descriptive Statistics
Empirical Rule – Burger N’ Brew
Define data range, output
location – request
Summary Statistics
Empirical Rule – Burger N’ Brew
Mean and Standard Deviation
Empirical Rule:
68% within 15.12 + (1)3.13
95% within 15.12 + (2)3.13
99.7% within 15.12 + (3)3.13)