How to Plot SVM Object in R (With Example)


You can use the following basic syntax to plot an SVM (support vector machine) object in R:

library(e1071)

plot(svm_model, df)

In this example, df is the name of the data frame and svm_model is a support vector machine fit using the svm() function.

The following example shows how to use this syntax in practice.

Example: How to Plot SVM Object in R

Suppose we have the following data frame in R that contains information about various basketball players:

#create data frame
df <- data.frame(points = c(4, 5, 5, 7, 8, 12, 15, 22, 25, 29),
                 assists = c(3, 4, 6, 8, 5, 6, 5, 6, 8, 12),
                 good = factor(c(0, 0, 0, 1, 0, 1, 0, 1, 1, 1)))

#view data frame
df

   points assists good
1       4       3    0
2       5       4    0
3       5       6    0
4       7       8    1
5       8       5    0
6      12       6    1
7      15       5    0
8      22       6    1
9      25       8    1
10     29      12    1

Suppose we would like to create a support vector machine that uses the variables points and assists to predict whether or not a player is good (0 = no, 1 = yes).

We can use the following code to fit the support vector machine and then plot the results:

library(e1071)

#fit support vector machine
model = svm(good ~ points + assists, data = df)

#plot support vector machine
plot(model, df)

The plot displays the values for the assists variable on the x-axis, the values for the points variable on the y-axis, and uses two different colors to display whether or not a player is predicted to be good (red) or not (yellow).

Note that you can use the color.palette argument within the plot() function to use a different color palette for the plot.

For example, we might choose to use the heat.colors color palette:

library(e1071)

#fit support vector machine
model = svm(good ~ points + assists, data = df)

#plot support vector machine using different color palette
plot(model, df, color.palette = heat.colors)

Other popular choices for the color.palette argument include:

  • rainbow
  • terrain.colors
  • topo.colors

Each color palette will produce different colors for the plot.

Additional Resources

The following tutorials explain how to perform other common tasks in R:

How to Filter for Unique Values Using dplyr
How to Filter by Multiple Conditions Using dplyr
How to Count Number of Occurrences in Columns in R

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