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Table 1 2-D cursor control results

From: A binary method for simple and accurate two-dimensional cursor control from EEG with minimal subject training

Subject Positives Negatives Moves # Bits # Moves TP% TN% CM%
  True False True False Correct Incorrect      
A 39 5 57 3 47 8 104 55 92.9% 91.9% 85.5%
B 44 12 33 4 43 16 93 59 91.7% 73.3% 72.9%
C 14 2 18 0 18 2 34 20 100.0% 90.0% 90.0%
D 29 1 17 0 24 1 47 25 100.0% 94.4% 96.0%
  1. Results from the four healthy subjects (one session per subject) using real hand movement with Laplacian derivation. For all subjects except Subject C, results are from the first session of game play following the initial threshold-setting task. For Subject C, there was a short intervening session of practice game play (see text). Positives are subjects' answers that the program classified as yes answers; Negatives were classified as no answers. True classifications were correct, and False classifications were incorrect. Correct Moves are cursor moves for which movement was in the direction intended by the subject; Incorrect Moves were in an unintended direction. The total number of yes/no answers given during each subject's games is # Bits, the sum of True Positives, False Positives, True Negatives, and False Negatives. The total number of cursor moves during each subject's games is # Moves, the sum of Correct Moves and Incorrect Moves. TP% is the true positive percentage, the percentage of intended yes answers that the program correctly classified. TP% is given by True Positives/(True Positives + False Negatives). TN% is the true negative percentage, the percentage of intended no answers that the program correctly classified. TN% is given by True Negatives/(True Negatives + False Positives). Chance level is 50% for both TP% and TN%. The false negative and false positive percentages (not shown) may be calculated by subtracting TP% and TN% from 100%, respectively. The correct bit percentage (not shown) may be calculated as 100% × (True Negatives + True Positives)/# Bits. CM% is the percentage of all cursor moves that were in the correct direction. Chance level for CM% is 31.2% (greater than 25% because when the cursor is at a grid edge, sometimes only one yes/no answer is required for a cursor move).