Description:
In this video we’ll show you how easy it is to perform a statistical analysis with NCSS. As an example, we’ll analyze a dataset that includes height and weight measurements from 14 men and 6 women. The goal of the analysis will be to create a model that can be used to predict a male’s weight based on his height. The dataset includes records for both males and females, so we’ll need to exclude the females before running the analysis.
To open the dataset, click Open on the toolbar and then select the file. We’ll load a dataset called “Regression” for this example. If your data are stored in another format like Excel or Access, that’s no problem because NCSS imports all major statistical and data file formats.
The Summary Statistics table provides quick summaries of the data in each column. It’s easy to change the statistics that are shown in the table. Each time the data are changed, the summary statistics table is automatically updated.
In this dataset, gender is stored in the 3rd column, so we’ll set a filter there so that only males are included in the analysis. Simple point-and-click tools make this easy! Notice that the display changes to indicate that some rows are now being excluded. The summary table is also updated to reflect the newly-filtered data.
NCSS includes a comprehensive list of statistics and graphic procedures. To perform a simple linear regression, use the menu or the procedure navigator to locate and load the linear regression procedure.
The procedure window makes it easy to set up the analysis because all of the options are located on a single input screen. As you mouse over the various options, the help pane provides in-depth information. If you’d like more help, click on the “Help” button to display the procedure documentation, which contains technical details and examples. Each procedure in NCSS is fully documented!
Since our goal is to predict Weight based on Height we’ll select Weight as the dependent variable and Height as the independent variable. By default, all of the reports and plots we probably need are already selected, but let’s go to the Plots tab to edit the Y versus X scatterplot. We’ll choose new plot colors and include prediction-limit lines. Notice that the format window displays a sample graph so we can see how each option change affects the plot.
With the options specified, click the green “Run” button to perform the analysis. The report is displayed in the output window. Use the navigation pane to quickly jump to various sections in the report. The regression estimation section of this report states the model we can use to make predictions about a man’s weight using height. The scatterplot gives a graphical representation of this relationship. Double-click the graph to enlarge it. All plots can easily be saved to any one of several file formats. You can also save the entire report or easily cut and paste individual sections into a document or presentation.
As you can see, it’s easy to perform a statistical analysis and create compelling graphs in NCSS, all in a matter of minutes. NCSS is powerful, comprehensive, and easy-to-use… and if you ever have any questions, our support team of Ph.D. statisticians will be happy to assist you!
To purchase NCSS or to obtain a no-obligation, free trial, visit ncss.com.