nlintool (Statistics Toolbox)

Fits a nonlinear equation to data and displays an interactive graph.

Syntax

nlintool(x,y,'model',beta0)
nlintool(x,y,'model',beta0,alpha)
nlintool(x,y,'model',beta0,alpha,'xname','yname')

Description

nlintool(x,y,'model',beta0) is a prediction plot that provides a nonlinear curve fit to (x,y) data. It plots a 95% global confidence interval for predictions as two red curves. beta0 is a vector containing initial guesses for the parameters.

nlintool(x,y,'model',beta0,alpha) plots a 100(1 - alpha) percent confidence interval for predictions.

nlintool displays a "vector" of plots, one for each column of the matrix of inputs, x. The response variable, y, is a column vector that matches the number of rows in x.

The default value for alpha is 0.05, which produces 95% confidence intervals.

nlintool(x,y,'model',beta0,alpha,'xname','yname') labels the plot using the string matrix, 'xname' for the X variables and the string 'yname' for the Y variable.

You can drag the dotted white reference line and watch the predicted values update simultaneously. Alternatively, you can get a specific prediction by typing the value for X into an editable text field. Use the pop-up menu labeled Export to move specified variables to the base workspace.

Example

See the section "Nonlinear Regression Models" in Chapter 1.