public void updateCognitiveVelocity() {
		for(int i = 0; i < velocities.length / 2; i++){
			for(int k = 0; k < velocities[i].length; k++){
				double normDevDist = calculateNormalisedDeviationDistance(k, positions[i][k], personalBest[i]);
				velocities[i][k] = weight * velocities[i][k] + normDevDist;
			}
		}
	}