To simulate a family of XY data sets with random error, start from any data table or graph, click Analyze, open the Simulate data category, and then select Simulate XY Data.

X values tab. Generate a regular series (arithmetic or geometric) of X values or use the X values from the data table you are analyzing.

Equation tab. You can choose to use Y values from the data table you are analyzing, and then add random scatter. More often, you will choose an equation on this tab.

Parameter values tab. On top of the tab, choose how many data sets you wish to simulate, and how many replicates each data set will have. The main part of the tab is where you enter the values of each parameter. If you choose to simulate more than one data set, then you can choose to enter a parameter value just for one data set, or to enter a parameter that applies to several, or all, curves. Choose the data sets on the top part of the dialog, and enter the parameter values for that data set (or that group of data sets) below.

Random error tab. Choose among several methods for generating random scatter and also adding outliers. Note that you may also choose to specify a "Random seed" when adding scatter to the generated values. By specifying a random seed, any time you run the simulation (with the same parameters and the same random seed), you will obtain exactly the same results. This is helpful when you want to replicate the results of a previous simulation experiment, or if you want to ensure that the values do not change if the analysis is recalculated.