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Language was confusing and misleading (see other answer). Tried to improve it.

In principle, accuracy is the fraction of properly predicted cases.

This is the same as 1 - the fraction of misclassified cases or 1 - the *error* (rate).

Both terms may be sometimes used in a more vague way, however, and cover different things like class-balanced error/accuracy or even F-score or AUROC -- it is always best to look for/include a proper clarification in the paper or report.

Also, note that test error rate implies error on a test set, so it is likely 1-test set accuracy, and there may be other accuracies flying around.

user88