o_18ufhu7n51jij1pedr1jjeu19lpa.pdf

Using the Computer 515
Cumulative Hours
of Training
Productivity
(in pounds per week)
0 70,000
100 70,350
250 70,500
375 72,600
525 74,000
750 76,500
875 77,000
1,100 77,400
1,300 77,900
1,450 77,200
1,660 78,900
1,900 81,000
2,300 82,500
(continued)
Cumulative Hours
of Training
Productivity
(in pounds per week)
2,600 84,000
2,850 86,500
3,150 87,000
3,500 88,600
4,000 90,000
Source: Adapted from “Delta Wire Corporation,” Strengthening America’s
Competitiveness: Resource Management Insights for Small Business Success.
Published by Warner Books on behalf of Connecticut Mutual Life Insurance
Company and the U.S. Chamber of Commerce in association with the Blue
Chip Enterprise Initiative, 1991, International Monetary Fund; Terri
Bergman, “TRAINING: The Case for Increased Investment,” Employment
Relations Today, Winter 1994–1995, pp. 381–391, available at http://www.
ed.psu.edu/nwac/document/train/invest.html. Bekaert Web site at: http://www.
bekaert.com/corporate/press/2006/31-jan-2006.htm.
USING THE COMPUTER
EXCEL
■
■
■
Excel has the capability of doing simple regression analysis.
For a more inclusive analysis, use the Data Analysis tool. For
a more “a la carte” approach, use Excel’s Insert Function.
To use the Data Analysis tool for a more inclusive analysis,
begin by selecting the Data tab on the Excel worksheet.
From the Analysis panel at the right top of the
Data tab worksheet, click on Data Analysis. If your Excel
worksheet does not show the Data Analysis option, then
you can load it as an add-in following directions given in
Chapter 2. From the Data Analysis pulldown menu,
select Regression. In the Regression dialog box, input the
location of the y values in Input Y Range. Input the location
of the x values in Input X Range. Input Labels and
input Confidence Level. To pass the line through the origin,
check Constant is Zero. To print out the raw residuals,
check Residuals. To print out residuals converted to z
scores, check Standardized Residuals. For a plot of the
residuals, check Residual Plots. For a plot of the line
through the points, check Line Fit Plots. Standard output
includes r, r 2 , s e , and an ANOVA table with the F test, the
slope and intercept, t statistics with associated p-values,
and any optionally requested output such as graphs or
residuals.
To use the Insert Function (f x ) go to the Formulas tab on
an Excel worksheet (top center tab). The Insert Function
is on the far left of the menu bar. In the Insert Function
dialog box at the top, there is a pulldown menu where it
says Or select a category. From the pulldown menu associated
with this command, select Statistical. Select
INTERCEPT from the Insert Function’s Statistical menu
to solve for the y-intercept, RSQ to solve for r 2 , SLOPE to
solve for the slope, and STEYX to solve for the standard
error of the estimate.
MINITAB
■ Minitab has a relatively thorough capability to perform
regression analysis. To begin, select Stat from the menu bar.
Select Regression from the Stat pulldown menu. Select
Regression from the Regression pulldown menu. Place the
column name or column location of the y variable in
Response. Place the column name or column location of
the x variable in Predictors. Select Graphs for options
relating to residual plots. Use this option and check Four in
one to produce the residual diagnostic plots shown in the
chapter. Select Options for confidence intervals and prediction
intervals. Select Results for controlling the regression
analysis output. Select Storage to store fits and/or
residuals.
■ To obtain a fitted-line plot, select Stat from the menu bar.
Select Regression from the Stat pulldown menu. Select
Fitted Line Plot from the Regression pulldown menu. In
the Fitted Line Plot dialog box, place the column name or
column location of the y variable in Response(Y).
■ Place the column name or column location of the x variable
in Response(X).Check Type of Regression Model as
Linear (Chapter 12), Quadratic,or Cubic.
■ Select Graphs for options relating to residual plots. Use
this option and check Four in one to produce the residual
diagnostic plots shown in the chapter.
■ Select Options for confidence intervals and prediction
intervals.
■ Select Storage to store fits and/or residuals.