Table 9.

Results of classifiers trained on a corresponding category from another source (N=500).

Training source	Test source	Category	Classifier	Accuracy, n (%)	Balanced accuracy
WebMD	DailyStrength	Psychological support	SVMa	328 (65.6)	0.656
WebMD	Google+Health	Share experiences	Random forest	428 (85.6)	0.584
DailyStrength	Google+Health b	Share experiences	CNNc	383 (76.6)	0.800
Twitter	Google+Health	Share experiences	SVM	408 (81.6)	0.770
Twitter	Google+Health	Share news	CNN	360 (72.0)	0.562

^aSVM: support vector machine.

^bThe test source, category, and balanced accuracy of each classifier that achieved a balanced accuracy of at least 0.75 are italicized for emphasis.

^cCNN: convolutional neural network.