This is a brief introduction to the three main stages in analysing data with the Windows version of Genstat. These are: loading data, performing the required analysis, and saving the results. If you are already familiar with the Genstat command language you may like to refer to Using the Genstat Command Language. A more complete introduction to Genstat can be found in the online Guide to Genstat: Introduction (pdf). This can be found by selecting Help | Genstat Guides | Introduction to Genstat for Windows.
The easiest way to enter new data into Genstat is by using a spreadsheet. From the menu bar select Spread, New, then Create. This will open a dialog in which you can specify the size and type of the spreadsheet. For the time being, the default settings can be used; click the OK button to continue. A window containing a spreadsheet of the default size (100 rows and 10 columns) will appear, with a * in every cell. This is how Genstat represents a “missing value” (an unknown quantity). To enter data in the spreadsheet click on the cell in row 1, column C1. This will be highlighted in blue, indicating that it is the current cell. You can now type a value, and press ENTER to move on to the next cell (row 2, column C1). Enter the following set of data in columns C1 and C2:
After entering the value 12 you will need to click on row 1, column C2 to move to the second column. Once all the data has been entered select the Spread | Delete | Empty Rows + Columns menu. This will shrink the spreadsheet to the size of the data that you have entered. The spreadsheet should now appear as shown above.
The data you have entered is displayed in the spreadsheet window but cannot be accessed by Genstat until it is saved as Genstat data. By default, this should happen automatically when you switch focus to any other window; you should see a number of messages appearing in the Output window to indicate this has occurred. If you click on the Data tab on the left hand panel, and then double-click the All Data folder, you should obtain a listing of the variables C1 and C2 (see below). If, for any reason, this automatic update does not appear to work (for example, it may have been disabled on the Spreadsheet Options) you can make the update manually. From the Spread menu select Update, then Changed Data to Genstat. This will create Genstat data structures containing your data. Messages should now appear in the Output window showing that your data has been successfully loaded.
You can also use a button on the toolbar to update your data to Genstat, by clicking on the button.
The Stats item on the menu bar lists various forms of analysis that can be performed on your data. For example, you can fit a straight line to the data that you have just entered. Select the Stats | Regression Analysis | Linear Models menu. This will bring up the Linear Regression menu that lets you specify your data and various other options controlling the analysis. Click in the box labelled Response Variate and then double-click on C2 in the Available Data list. Likewise, set the Explanatory Variate to C1. Then click on Run. The following image shows the menu with the data entered.
The results from the regression of C2 on C1 will appear in the Output window. You can use the scroll bar to move up and down in the window if it is not large enough to display all the output at once. Returning to the Linear Regression menu you can use the Further Output button to produce more output from the analysis. For example, clicking the Graph of Fitted Model button will open the Genstat Graphics Viewer containing a graph of the data and fitted line.
Saving the Results
The results of the regression analysis are contained in the Output window. You can save this to a file by selecting File | Save As and then specifying an appropriate name for the saved output. Note that the File menu always operates on the currently active window, which is indicated by highlighting the title bar. Click on the title bar of the Output window to ensure it is the active window before using the File menu.