A clutch disk for use with a vehicle clutch having a carrier plate to which facing carrier elements are attached that are pretensioned against each other in the axial direction. The DMT test can also be used to analyze the cause of a problem, or to predict a problem, whereby a pair of ADSL DMT modems could fail to synchronize. The amount of phase rotation is dependent on the number of channels used to form the higher rate channel. In use, the first information and the second information are correlated for gauging an effect of the advertisement on the user activity involving the second medium.