minitab vs jmp

7/28/2019 Minitab vs Jmp

1/13

OR/MS Today- August 2007

Software Review

Minitab 15

One of the "big beasts" of statistical computing capable of much more than

basic use.

By Wayne Holland

I recently completed asoftware review forOR/MS Today of JMP 6.0.3, so I thought it

would be interesting to write a comparative review for Minitab 15

a statistical packageversus a statistical package.

The focus of my review of JMP was on the user-friendliness of performing basic

statistical analyses. I did not investigate the more advanced features because I was

interested in considering whether JMP was a good option for the managementscience/operations research professional with either some data to get a handle on or to

perform some basic statistical analysis on. I was mainly interested in how easy is it to get

something meaningful out. This, therefore, sets the tone of my analysis of Minitab. The

software review editor tells me that Minitab is almost synonymous with Six Sigma and isheavily favored by practitioners JMP is a relative newcomer to Six Sigmabut Six

Sigma is not a part of my review.

I am sure readers are aware that Minitab is a long-established standard in the statistical

analysis business and capable of much more than the basic use. My last encounter with

Minitab was 20 years ago as an undergraduate working on analyzing Box-Jenkinsforecasting problems on a mainframe computer. All those DOS-type commands one had

to type, such as COPY C1 C2 and ARIMA (1,1), come back to me as a ghost from a past-

life when I used to be good at statistics! These days, desktop packages strive for menu-

driven smoothness, and I was pleased to see that the new Minitab is no exception.Minitab is one of the big three (along with SAS and SPSS) in the statistical computing

business. My question is: Is Minitab best left to the heavyweight statistical user, or does it

have something to offer everyone else as well?

Installation

In some past software reviews forOR/MS Today (Holland, 2003, 2005) over the past fewyears I have encountered installation difficulties. I am pleased to report that Minitab

installed simply and cleanly. I was in a position to start working within minutes.
http://www.lionhrtpub.com/ORMS.shtmlhttp://www.lionhrtpub.com/ORMS.shtmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/ORMS.shtml


2/13

Basic Use of Minitab

F ir st time usage. When Minitab is run, it opens to the screen shown in Figure 1. It uses a

two-window system: one called Worksheet, rather like a spreadsheet, for holding thedata, and the other called Session, to which output of analyses is added. Thus, at the end

of the session, all of the output, except graphs and charts, will be contained in linearformat in this window. I have never quite understood why, if the package works on the

basis of "all output going to one report" that some bits of output don't go to that report. It

seems inconsistent to me. But I guess that's just me being prissy and neat!

Figure 1: Initial screen of Minitab. The Session Window will display results; the Data Window willcontain the data you wish to analyse.

Access to all graphical tools, such as histograms, scatterplots and 3-D surface plots, is viathe single-menu item "Graph." Similarly, all statistical analyses are stored under the

general menu item "Stat." Clicking on this opens up a sub-menu offering the following

statistical analyses: basic statistics, regression, anova, DOE, control charts, quality tools,

reliability/survival, multivariate, time series, tables, non-parametrics, EDA, power andsample size. It is a neat, logical arrangement to allow self-contained areas of statistics to

be explored without needs to understand everything before being able to make sensibleprogress.

Example data. To investigate using Minitab, I used exactly the same data file that I used

for the JMP review. It is a data file I created for student coursework. The file is an Excelspreadsheet containing the Forbes Global 2000 companies as of Sept. 20, 2005. I took the

data fromwww.forbes.com. Figure 2 shows the first 11 rows, showing the top 10

companies and the data collected byForbes to produce the ranking. There are four
http://www.forbes.com/http://www.forbes.com/http://www.forbes.com/http://www.forbes.com/


3/13

quantitative variables (sales, assets, profit and market value) and two categorical

variables (country and industry sector/category). For the JMP review, I performed some

exploratory data analysis, produced scatterplots and correlations, and then performed amultiple regression with validation and a hypothesis test that required the creation of new

"flag" variable to separate out data stacked in a single column. Finally, I investigated 3-

dimensional plotting facilities. The intention is to repeat these exercises here andcompare the ease of production and the quality of the final result.

Figure 2: Sample of data from the Excel worksheet imported into Minitab.

The Excel data file appeared to be read in very easily by Minitab. It is displayed in Figure

3. For columns read in as text, "-T" is appended to the column heading. This is a usefulconfirmation that the data has been read in correctly. However, when I started to attempt

analyses involving the Category column, C4-T, error messages were produced sayingthere were unequal numbers of observations in each column. I scanned down the rows

and all columns appeared to stop at row 2,000. However, it finally emerged that there was

a stray entry 37 rows below the end of the data set. This was careless on my part, but Iwas somewhat annoyed that Minitab did not fill in rows 2,001 to 2,036 with "*" to

indicate that it thought there were missing values in these rows. This is what Minitab

does with missing values in a data set. The fact that Minitab did not fill in these rows

indicated to me that it did not consider them part of the data set and hence there shouldhave been no problem! Also, a column of "*" beyond row 2,000 would certainly have

helped me flag up this issue in less time than I wasted on it.


4/13

Figure 3: Excel data imported into Minitab.

It is reasonably intuitive to perform basic exploratory data analysis immediately, without

reference to the documentation. I created bar charts, scatterplots and summary statistics toget a feel for the data. However, one feature I didn't like was in the production of a bar

chart of mean sales and mean market value categorized by industry sector. What I wanted

was the sectors listed across the horizontal axis, with two bars at each category to

represent the relevant mean sales and mean market value. What I got was Figure 4, whichis a bar chart of mean sales by category followed by a bar chart of mean market value.

This required a two-stage process displayed in Figure 5 and Figure 6. It may very well bepossible to produce the result I was looking for, but it is certainly not easy to find fromthe options offered, nor by reference to the user guide. [Editor's note: According to Jay

Aubuchon, product manager at Minitab, choosing "Graph variables displayed innermost

on scale" would produce the desired result in the dialog box shown in Figure 6.]

Figure 4: Bar chart of profits and market value averages by industry sector.


5/13

Figure 5: Creation of Figure 4 in Minitab. Having selected Stat ... Bar Chart, the statistic to bepresented is selected and the type of presentation required.

Figure 6: Creation of Figure 4 in Minitab. Following on from Figure 5, a second form is displayed toselect variables to be displayed and categorization variable.

At this point, I also came across another feature I didn't like: the lack of interactivity on

graph manipulation. I was expecting to be able to grab axes and elongate or shrink them.

However, they were entirely fixed. I could reduce the size of the box in which the chart

was presented, but I couldn't enlarge it. I could make these changes by calling up therelevant menu items for re-scaling and typing in new values, but this seems very

restrictive and old-fashioned in comparison with JMP. It is obviously a relic of Minitab's


6/13

heritage as a mainframe computer package, but this sort of issue should be dealt with in

the transference to PC package. [Editor's note: According to Aubuchon, this is a

consequence of Minitab's choice to edit graphs like Excel, and has nothing to do withheritage.]

The production of scatter-plots and correlation matrix for the four quantitative variablessales, assets, profits and market value (Figure 7) also surprised me. Rather than offering

me a default option of correlating all variables against all others, I had to fill in the table,

shown in the center of Figure 8, identifying which pairs I required to view. This seems arather cumbersome way to proceed. [Editor's note: According to Aubuchon, Graph >

Matrix Plot would produce the desired result.] The required correlation matrix, with

associated p-value below each correlation, was added to the Session window. The scatter-

plots were created in a separate chart window.

Figure 7: Scatterplots and correlation matrix for sales, profits, assets and market value. Note that thecorrelation coefficients and p-values of significance test are added to the session window, with thescatterplots displayed in a separate window.


7/13

Figure 8: Creation of Figure 7. Note that in the central table each pair of variables for which ascatterplot is required has to be entered. There appeared to be no default option for viewing all pairs.

Next I wanted to experiment with two specific statistical analyses:

1. A multiple regression explaining market value in terms of sales and assets andtesting three of the assumptions of the linear model autocorrelation, normalityof residuals and homoscedasticity of residuals.

2. A hypothesis test to investigate whether there was a significant differencebetween average U.S. and non-U.S. company profits.

Mul tiple regression. There are various regression options easily accessible via the Stat ...Regression Menu, such as stepwise, partial least squares and various logistic regression

methods. However, for illustration, I created directly the multiple regression model:

Market Valuei = _ + _1 Salesi + _2 Assetsi + _i

This is completed very intuitively and with little effort. The result is shown in Figure 9,which gives not only the model but also all the validation information required, such as

test for normality of residuals, durbin-watson to test for autocorrelation and scatterplot of

residuals against fitted for heteroscedasticity. This is a well-handled, strong aspect toMinitab, and better, in my view, than the two-stage process required in JMP.


8/13

Figure 9: Multiple regression output for Market Valuei = + 1 Salesi + 2 Assetsi + i Note that the model and all the usual validation tests are displayed in one analysis.

Hypothesis test. I was interested to see whether there was a difference in average

profitability for U.S. firms compared to non-U.S. firms in the Forbes 2000 ranking. Thisrequired setting up a new column with a "flag" variable which contains either "Y" or "N"

(or any bi-value pair) to represent "U.S. company" or not. This would allow the data in

the Profit column to be divided into the two relevant data sets. This was fairly intuitive toachieve (it didn't require me to look in help anyway!). Via the Editor ... Formula ...

Assign Formula to Column options, Figure 10 was produced showing a form to fill in to

calculate the new column. The layout of this form makes it fairly obvious how to set upthe necessary IF condition. Anyone who has ever used an IF statement in Excel will haveno problems with this feature. The required analysis follows easily (Figure 11).


9/13

Figure 10: Creation of a conditional statement to set up the new column in C9.

Figure 11: Output for the hypothesis test on whether or not company mean profits are the same for

US and non-US companies.

3-D plots. Finally, I was interested in creating a 3-dimensional plot. Maybe not the mostessential example, but given the data I was working with, I decided to create a plot of

market value as a function of assets and sales (Figure 12). This allows for direct

comparison with JMP. The surface plotting tool is perfectly adequate, but it doesn't havethe interactivity of JMP. You can right-click on an axis and get a form to adjust scale

(Figure 13), or right-click on the graph and get a form that allows control of Graph


10/13

Attributes, Graph Size, Figure Location and Figure Attributes. In JMP, all this is done by

click and point at the figure with the mouse. It doesn't materially make much difference

to the final product, it's just more fun getting there!

Figure 12: Surface plot of market value against assets and sales.

Figure 13: The menu driven approach to re-scaling axes and graph size. It is not possible to do thisinteractively by the "click and drag" approach.

Advanced Features


11/13

Anyone familiar with using Minitab regularly will probably consider what I have written

a travesty. Minitab is a much bigger, more sophisticated package than I have been able tocover in the above. It does much, much more with the same menu-driven approach, such

as design of experiments, control charts, quality tools and forecasting. Minitab has been

one of the three big players in statistical software for a very long time. Its historicalstanding is clearly a strength in already having a large, devoted following and areputation for reliability. The danger comes from new products, such as JMP, built

specifically for PC operating systems that are more able to exploit interactivity than a

more mature package making a transition with considerable baggage.

Quality of Documentation

Minitab comes with a very slim (approximately 150-page) "Meet Minitab" introductoryguide. In essence it tells you what you need to know to get started. It is also supported by

quite extensive help built into Minitab, including a good set of helpful tutorials to workthrough and a very nice "Methods and Formulas" page, which is essentially a "how to" ofvarious statistical analytical methods (Figure 14). Personally, I prefer a little more paper-

based documentation, but I fully concede I am probably in the minority in that respect

these days.

Figure 14: Part of the in-built help facility in Minitab. Here are methods and formula for variousstatistical procedures. By clicking on a particular link, instructions are given about how to performthat analysis in Minitab.

New Features of Minitab 15


12/13

Not having used Minitab since version 4 or 5 in my student days, I am not familiar with

what is new from Minitab 14. However, the Minitab Web site claims: "Minitab 15contains nearly 50 enhancements with minimal changes to the interface, making it simple

for current users to access all the new features. Highlights include:

assign formulas to columns in the worksheet expanded gage R&R capabilities power (OC) curves for power and sample size probability distribution plot new reliability methods for forecasting future warranty claims"

Conclusion

Minitab remains with SPSS and SAS as one of the big beasts of statistical computing.The already committed user does not need to read anything from me to decide whether or

not they will use it. For the new user, particularly with modest statistical needs, Minitab

is certainly an accessible option and is not formidable in terms of inducting oneself intoits use. However, if you are coming totally new to a statistical package, I would give

serious consideration to JMP, which beats Minitab on interactivity, while matching

functionality. But in the final analysis, it's a question of personal preference rather than

killer knockout blow. It's your money; you make the choice!

Product Information

Minitab 15 is available from Minitab Inc.

Address: Quality Plaza, 1829 Pine Hall Road, State College,

PA 16801Phone: 1-814-238-3280

Fax: 1.814.238.2035

E-mail:[email protected] site:www.minitab.com

PricingProfessional version: Single perpetual use license: $1,195.

Annual use licenses and volume discounts available. Visithttp://minitab.com/products/pricing/for details.

Academic version: Students, professors and other qualified

staff from educational institutions in eligible countries may
mailto:[email protected]:[email protected]:[email protected]://www.minitab.com/http://www.minitab.com/http://www.minitab.com/http://minitab.com/products/pricing/http://minitab.com/products/pricing/http://minitab.com/products/pricing/http://www.minitab.com/mailto:[email protected]


13/13

purchase and download unit copies and upgrades from e-academy, a leading provider of brand name software

discounted for education. Options include 6- or 12-month

rentals, as well as perpetual use unit copies of Minitab 15.Visit e-academy for more information.

System requirements

Operating Systems: Microsoft Windows 2000, XP or Vista

RAM: 512 MB or more

Processor: 1 GHz 32-bit or 64-bit processorScreen resolution: 1024 x 768 or higher

Hard disk space: 125 MB (minimum) free space available

PDF Reader: Acrobat Reader 5.0 or higher required for Meet

Minitab

Wayne Holland is an associate professor (senior lecturer) in operations research at

Cass Business School, City University, London, U.K. He teaches quantitative methodsand management science to undergraduate, MBA and Executive MBA students. His

research interests are in design and analysis of simulation models to investigate risk-

related issues, particularly operational risk in banking and supply chain risk.

References

1. Holland, W., 2003, "Software Review: @Risk Version 4.5 Pro," OR/MS Today, Vol. 30, No. 1,pp. 52-55.

2. Holland, W., 2005, "Software Review: Crystal Ball v 7.0.1 Professional," OR/MS Today, Vol. 32,No. 2, pp. 54-57.

3. Holland, W., 2007, "Software Review: JMP 6.0.3," OR/MS Today, February 2007 issue, Vol. 34,No. 1, pp. 66-72.

4. "Meet Minitab 15," 2007, provided with software.

Table of Contents OR/MS TodayHome Page

OR/MS Todaycopyright 2007 bythe Institute for Operations Research and the Management Sciences. All

rights reserved.

Lionheart Publishing, Inc.506 Roswell Rd., Suite 220, Marietta, GA 30060 USAPhone: 770-431-0867 | Fax: 770-432-6969E-mail:[email protected]:http://www.lionhrtpub.com

Web Site Copyright 2007 by Lionheart Publishing, Inc. All rights reserved.
http://www.lionhrtpub.com/orms/orms-2-03/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-03/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-03/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-4-05/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-4-05/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-4-05/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-8-07/tocfr.htmlhttp://www.lionhrtpub.com/orms/orms-8-07/tocfr.htmlhttp://www.lionhrtpub.com/ORMS.shtmlhttp://www.lionhrtpub.com/ORMS.shtmlhttp://www.lionhrtpub.com/ORMS.shtmlhttp://www.informs.org/http://www.informs.org/http://www.informs.org/mailto:[email protected]:[email protected]:[email protected]://www.lionhrtpub.com/http://www.lionhrtpub.com/http://www.lionhrtpub.com/http://www.lionhrtpub.com/mailto:[email protected]://www.informs.org/http://www.lionhrtpub.com/ORMS.shtmlhttp://www.lionhrtpub.com/orms/orms-8-07/tocfr.htmlhttp://www.lionhrtpub.com/orms/orms-2-07/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-4-05/frswr.htmlhttp://www.lionhrtpub.com/orms/orms-2-03/frswr.html

minitab vs jmp

Documents