Figure 6.21 shows the Model window for a design with two continuous factors (X1 and X2) and one two-level categorical factor (X3).
Figure 6.21 Simulate Responses Control Window
•
|
1.
|
For each term in the list of Effects, enter coefficients for the linear model used to simulate the response values. These define a linear function, L(x, β) = x‘β. See the Simulate Responses outline in Figure 6.21:
|
–
|
The vector x consists of the terms that define the effects listed under Effects.
|
–
|
The vector β is the vector of model coefficients that you specify under Y.
|
3.
|
Click Apply. A <Y> Simulated column containing simulated values and their formula is added to the design table, where Y is the name of the response column.
|
Simulates values from a normal distribution. Enter a value for Error σ, the standard deviation of the normal error distribution. If you have designated factors to have Changes of Hard in the Factors outline, you can enter a value for Whole Plots σ, the whole plot error. If you have designated factors to have Changes of Hard and Very Hard, you can enter values for both the subplot and whole plot errors. When you click Apply, random values and a formula containing a random response vector based on the model are entered in the column <Y> Simulated.
Simulates values from a binomial distribution. Enter a value for N, the number of trials. Random integer values are generated according to a binomial distribution based on N trials with probability of success 1/(1 + exp(-L(x, β))). When you click Apply, random values and their formula are entered in the column <Y> Simulated. A column called N Trials that contains the value N is also added to the data table.
Simulates random integer values according to a Poisson distribution with parameter exp(L(x, β)). When you click Apply, random values and their formula are entered in the column <Y> Simulated.
Note: You can set a preference to simulate responses every time you click Make Table. To do so, select File > Preferences > Platforms > DOE. Select Simulate Responses.