STATGRAPHICS Centurion Tutorial

STATGRAPHICS is an easy-to-learn, easy-to-use PC-based statistics software package with an intuitive design that will make your everyday data analysis easier than you ever imagined.

Upon entering StatGraphics for the first time, you will be greeted with a StatWizard pane, which will ask you

What task do you wish to perform?

To make things simple, toggle off the "Show the StatWizard at Setup" option. [i.e. clear the box].

Then select OK.

Since you will be either entering data or using an existing data file, select the appropriate option (do either one the first time through).

#### GETTING AROUND STATGRAPHICS

When you enter STATGRAPHICS, it displays an untitled data icon (middle of screen), a StatAdvisor icon, a StatGallery icon, an untitled Comments icon and a StatReporter icon. When you are ready to start working, you can either enter new data or use an existing file. The existing files can be either StatGraphics files, spreadsheets (EXCEL) or data files from other software packages. For our class we will restrict our data files to either StatGraphics file (SF, SF3, or SF6 extensions) or EXCEL files (XLS extensions). [The StatGraphics software and manuals mention Statfolios, but to keep things simple at the outset, we will ignore Statfolios from our discussion].

#### EXAMPLES

We now present a number of examples.

EXAMPLE 1. Opening an existing StatGraphics data file, generating descriptive statistics and printing out the generated statistics.

For this example we will be obtaining descriptive statistics from a data file, CARDATA.SF, which contains 154 observations for cars. In particular we will be getting statistics about the random variable MPG, which represents the miles per gallon of gasoline. Note that CARDATA.SF is a StatGraphics file.

• To Open the Data File:
1. Select File...Open...Open Data Source... OK (when STATGRAPHICS Data File is selected) from the menu bar or click the Open Data File button on the system toolbar.

Helpful Hint: For a description of the buttons on the system and analysis toolbars, simply place the cursor on the button and a description of the button appears just below the cursor.

1. Double-click on the Data file/folder. Double-click on cardata.sf from the scrolling list that appears below the File Name text box. The system opens the data file and displays the data icon with the file name (see the lower left corner of the screen).
• To Generate the Descriptive Statistics such as mean (average), standard deviation, …
1. Select Describe……… Numeric Data…….. One Variable Analysis
2. Double click on mpg
3. Click the OK button to display the Analysis Summary.
4. Click on the Tables button (icon with 3 “T”) on the analysis toolbar to display the Tables dialog box. Select one or as many options as you like. To follow our example, select Analysis Summary, Summary Statistics and Stem-and -Leaf display.
5. Click the OK button.

Helpful Hint: To see other options that are available for an analysis, click the right mouse button on the pane of that analysis and select Analysis Options...To maximize a pane, double-click on it; to minimize it, double-click again.

1. Click the Graphs button (icons with 2 “G”) on the analysis toolbar. The system displays the Graphs dialog box. Select one or as many options as you like. To follow our example, select Frequency Histogram.
2. Click on the OK button.
3. After reviewing the results, click the Minimize button to shrink the window to an icon.

How many observations are there for the variable mpg? What are the average and the standard deviation of the variable mpg?

To clear the output for analysis of new data sets, select File ... Close ... Close StatFolio and select “NO” to “Do you want to save the current StatFolio?”

EXAMPLE 2. Opening an EXCEL file.

Rather than provide you with an EXCEL file, you will create an EXCEL file that you will later open up as a data file in StatGraphics for Windows.

• Enter the following, in an EXCEL spreadsheet, where mpg is in cell A1, 24 in A2, 34 in A3,…..
 mpg 24 34 45 36 43 34 24 14 31 33 35 38
• Save the spreadsheet as an EXCEL 97-2003 WORKBOOK titled CAR.XLS on your data disk.

When the above information is read in as data to StatGraphics for Windows, mpg will represent the name of the variable.

• To Open the Data File:

1. Close the file CAR.XLS in Excel first.  In StatGraphics, select File...Open...Open Data Source and check “External Data File”.

2. Browse to the folder with the file CAR.XLS.

3. Now just select the file CAR.XLS.

The data is now ready for analysis!!

EXAMPLE 3. Creating a horizontal time series graph, which can then be inserted into a WORD document.

There is a file called, TSDATA.SF. This StatGraphics file contains a variable bubbly, which represent monthly champagne sales for a firm. We will create a horizontal time series plot for bubbly and then import (insert) it into a WORD document.

• Select File...Open...Open Data Source... OK (when STATGRAPHICS Data File is selected) from the menu bar or click the Open Data File button on the system toolbar. Select the file  TSDATA.SF
• From the main toolbar
1. Select DESCRIBE…..TIME SERIES ……DESCRIPTIVE METHODS
2. Click on bubbly and then click on the big arrow to move "bubbly" to the Data field.
3. Click on the OK button.
4. On the analysis toolbar, click on Graphs button (icons with 2 “G”). There are a number of options. For our example, Horizontal Time Sequence Plot is already selected by default.
5. Click on the OK button.
6. To maximize the plot, double click on it.
7. Select Describe……… Numeric Data…….. One Variable Analysis and double click on “bubbly” to find the average and standard deviation.

How many observations are there for the variable bubbly? What are the average and the standard deviation of the variable bubbly?

Save the data file TSDATA.SF in a directory such as Desktop: select FILE…SAVE AS…SAVE DATA FILE AS … Name the file TSDATA.

Save the output: If you want to save all the output you have produced in StatGraphics, select FILE…SAVE AS…SAVE STATFOLIO AS and name the file BUBBLY.sgp. Make sure you save this StatFolio file BUBBLY.sgp in the same directory as the data file TSDATA. Now close StatGraphics. In My Computer or Windows Explorer, browse to the directory you saved both BUBBLY.sgp and TSDATA.SF and double click on the file BUBBLY.sgp. You have just re-opened all analysis you saved before!

Copy graphs to MS WORD: If you want to insert the plot into a WORD document proceed as follows

1. Now to save the graph so it can be imported into a WORD document, Right Mouse click in the graph you want to copy and select Save Graph.... Note the graph will be saved as a Windows Metafile (*.wmf). Provide a name and storage location. We suggest as an example, BUBPLOT.wmf
2. Go into the WORD document where you want to insert the graph and select INSERT….PICTURE…FROM FILE. The single left click on the file (BUBPLOT.wmf). To resize the inserted plot, one can double click on the inserted plot and then resize it using the mouse cursor.
3. Print WORD document as you would any other WORD document.