Statistics: svmpredict

### Function Reference: `svmpredict`

statistics: predicted_label = svmpredict (labels, data, model)
statistics: predicted_label = svmpredict (labels, data, model, libsvm_options)
statistics: [predicted_label, accuracy, decision_values] = svmpredict (labels, data, model, libsvm_options)
statistics: [predicted_label, accuracy, prob_estimates] = svmpredict (labels, data, model, libsvm_options)

This function predicts new labels from a testing instance matrtix based on an SVM model created with `svmtrain`.

- labels : An m by 1 vector of prediction labels. If labels of test data are unknown, simply use any random values. (type must be double)
- data : An m by n matrix of m testing instances with n features. It can be dense or sparse. (type must be double)
- model : The output of `svmtrain` function.
- `libsvm_options` : A string of testing options in the same format as that of LIBSVM.

`libsvm_options` :

- `-b` : probability_estimates; whether to predict probability estimates. For one-class SVM only 0 is supported.

| 0 | return decision values. (default)
| 1 | return probability estimates.

- `-q` : quiet mode. (no outputs)

The `svmpredict` function has three outputs. The first one, predicted_label, is a vector of predicted labels. The second output, accuracy, is a vector including accuracy (for classification), mean squared error, and squared correlation coefficient (for regression). The third is a matrix containing decision values or probability estimates (if `-b 1`’ is specified). If k is the number of classes in training data, for decision values, each row includes results of predicting k(k-1)/2 binary-class SVMs. For classification, k = 1 is a special case. Decision value +1 is returned for each testing instance, instead of an empty vector. For probabilities, each row contains k values indicating the probability that the testing instance is in each class. Note that the order of classes here is the same as `Label` field in the model structure.

Source Code: svmpredict