plotSlice
Plot of slices through fitted generalized linear regression surface
Description
plotSlice(
creates a figure
containing one or more plots, each representing a slice through the regression
surface predicted by mdl
)mdl
. Each plot shows the fitted response
values as a function of a single predictor variable, with the other predictor
variables held constant.
plotSlice
also displays the 95% confidence bounds for the
response values. You can specify the type of confidence bounds, and select which
predictors to use for each slice plot. For more information, see Tips.
Examples
Input Arguments
Tips
The Confidence Interval Type options in the figure window allow you to select simultaneous or non-simultaneous confidence bounds.
Simultaneous (default) —
plotSlice
computes confidence bounds for the curve of the response values using Scheffé's method. The range between the upper and lower confidence bounds contains the curve consisting of true response values with 95% confidence.Non-Simultaneous —
plotSlice
computes confidence bounds for the response value at each observation. The confidence interval for a response value at a specific predictor value contains the true response value with 95% confidence.
With simultaneous bounds, the entire curve of true response values is within the bounds at high confidence. By contrast, non-simultaneous bounds require only the response value at a single predictor value to be within the bounds at high confidence. Therefore, simultaneous bounds are wider than non-simultaneous bounds.
If you do not want the plot to display confidence bounds, you can uncheck the Show Confidence Intervals in Plot box.
The Predictors list in the figure window lets you select which predictors to use for each slice plot. If the regression model
mdl
includes more than eight predictors,plotSlice
creates plots for the first five predictors by default.
Alternative Functionality
Use
predict
to return the predicted response values and confidence bounds. You can also specify the confidence level for confidence bounds by using the'Alpha'
name-value pair argument of thepredict
function. Note thatpredict
finds nonsimultaneous bounds by default, whereasplotSlice
finds simultaneous bounds by default.A
GeneralizedLinearModel
object provides multiple plotting functions.When verifying a model, use
plotDiagnostics
to find questionable data and to understand the effect of each observation. Also, useplotResiduals
to analyze the residuals of the model.After fitting a model, use
plotPartialDependence
to understand the effect of a particular predictor. Also, useplotSlice
to plot slices through the prediction surface.