Kaiser effect (material science) Kaiser effect (material science) The Kaiser effect is a phenomenon observed in geology and material science that describes a pattern of acoustic emission or seismicity in a body of rock or other material subjected to repeated cycles of mechanical stress. In material that exhibits an initial seismic response under a certain load, the Kaiser effect describes the absence of acoustic emission or seismic events until that load is exceeded. The Kaiser effect results from discontinuities (fractures) created in material during previous steps that do not move, expand, or propagate until the former stress is exceeded. Induced seismicity associated with fluid
The Superstar Effect The Superstar Effect The Superstar Effect or "Tiger Woods effect" refers to the change in performance caused by the presence of a highly ranked player - a superstar - in a rank-order competition. The phenomenon was first described in a study titled ""Quitters Never Win: The (Adverse) Incentive Effects of Competing with Superstars"" by Jennifer Brown, which examined the performance of golfers at events with and without Tiger Woods. In contradiction to what intuition would suggest (namely that increased rivalry encourages better performance), Brown finds that the presence of a superstar is in fact associated with reduced competitor’s efforts in