plotResiduals

Class: NonLinearModel

Plot residuals of nonlinear regression model

Syntax

plotResiduals(mdl)
plotResiduals(mdl,plottype)
plotResiduals(mdl,plottype,Name,Value)
h = plotResiduals(___)


Description

plotResiduals(mdl) creates a histogram plot of the nonlinear regression model (mdl) residuals.

plotResiduals(mdl,plottype) specifies the residual plot type plottype.

plotResiduals(mdl,plottype,Name,Value) specifies additional options using one or more name-value arguments. For example, you can specify the residual type and the graphical properties of residual data points.

h = plotResiduals(___) returns graphics objects for the lines or patch in the plot using any of the input argument combinations in the previous syntaxes. Use h to modify the properties of a specific line or patch after you create the plot. For a list of properties, see Line Properties and Patch Properties.

Input Arguments

mdl	Nonlinear regression model, constructed by fitnlm.
plottype	Character vector or string scalar specifying the type of plot: 'caseorder' Residuals vs. case (row) order 'fitted' Residuals vs. fitted values 'histogram' Histogram 'lagged' Residuals vs. lagged residual (r(t) vs. r(t–1)) 'probability' Normal probability plot 'symmetry' Symmetry plot Default: 'histogram'

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Note

The graphical properties listed here are only a subset. For a complete list, see Line Properties for lines and Patch Properties for histogram. The specified properties apply to the appearance of residual data points or the appearance of the histogram.

Color	Color of the line or marker, specified as an RGB triplet, hexadecimal color code, color name, or short name for one of the color options listed in the following table. For a custom color, specify an RGB triplet or a hexadecimal color code. An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1]; for example, [0.4 0.6 0.7]. A hexadecimal color code is a character vector or a string scalar that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Thus, the color codes '#FF8800', '#ff8800', '#F80', and '#f80' are equivalent. Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and hexadecimal color codes. Color Name Short Name RGB Triplet Hexadecimal Color Code Appearance 'red' 'r' [1 0 0] '#FF0000' 'green' 'g' [0 1 0] '#00FF00' 'blue' 'b' [0 0 1] '#0000FF' 'cyan' 'c' [0 1 1] '#00FFFF' 'magenta' 'm' [1 0 1] '#FF00FF' 'yellow' 'y' [1 1 0] '#FFFF00' 'black' 'k' [0 0 0] '#000000' 'white' 'w' [1 1 1] '#FFFFFF' Here are the RGB triplets and hexadecimal color codes for the default colors MATLAB® uses in many types of plots. RGB Triplet Hexadecimal Color Code Appearance [0 0.4470 0.7410] '#0072BD' [0.8500 0.3250 0.0980] '#D95319' [0.9290 0.6940 0.1250] '#EDB120' [0.4940 0.1840 0.5560] '#7E2F8E' [0.4660 0.6740 0.1880] '#77AC30' [0.3010 0.7450 0.9330] '#4DBEEE' [0.6350 0.0780 0.1840] '#A2142F'
LineWidth	Width of the line or edges of filled area, in points, a positive scalar. One point is 1/72 inch. Default: 0.5
Marker	Marker symbol, specified as one of the values in this table. Marker Description Resulting Marker 'o' Circle '+' Plus sign '*' Asterisk '.' Point 'x' Cross '_' Horizontal line '|' Vertical line 's' Square 'd' Diamond '^' Upward-pointing triangle 'v' Downward-pointing triangle '>' Right-pointing triangle '<' Left-pointing triangle 'p' Pentagram 'h' Hexagram 'none' No markers Not applicable
MarkerEdgeColor	Marker outline color, specified as an RGB triplet, hexadecimal color code, color name, or short name for one of the color options listed in the Color name-value argument.
MarkerFaceColor	Fill color for filled markers, specified as an RGB triplet, hexadecimal color code, color name, or short name for one of the color options listed in the Color name-value argument.
MarkerSize	Size of the marker in points, a strictly positive scalar. One point is 1/72 inch.

ResidualType

Type of residual used in the plot: 'Raw' Observed minus fitted values 'Pearson' Raw residuals divided by RMSE 'Standardized' Raw residuals divided by their estimated standard deviation 'Studentized' Raw residuals divided by an independent (delete-1) estimate of their standard deviation Default: 'Raw'

Output Arguments

h

Graphics objects corresponding to the lines or patch in the plot, returned as a graphics array. Use dot notation to query and set properties of the graphics objects. For details, see Line Properties and Patch Properties. You can use name-value arguments to specify the appearance of residual data points or the appearance of the histogram, corresponding to the first graphics object h(1).

Examples

Residual Plot

Plot the residuals of a fitted nonlinear model.

Load the reaction data and fit a model of the reaction rate as a function of reactants.

load reaction
mdl = fitnlm(reactants,rate,@hougen,[1 .05 .02 .1 2]);

Plot the residuals of the fitted model.

plotResiduals(mdl)

Residual Probability Plot

Create a normal probability plot of the residuals of a fitted nonlinear model.

Load the reaction data and fit a model of the reaction rate as a function of reactants.

load reaction
mdl = fitnlm(reactants,rate,@hougen,[1 .05 .02 .1 2]);

Create a normal probability plot of the residuals of the fitted model.

plotResiduals(mdl,'probability')

Tips

• The data cursor displays the values of the selected plot point in a data tip (small text box located next to the data point). The data tip includes the x-axis and y-axis values for the selected point, along with the observation name or number.