Seismic noise subsoil in order to draw seismic microzonation maps showing the predicted ground response to earthquakes. Research on the origin of seismic noise indicates that the low frequency part of the spectrum (below 1 Hz) is due to natural causes, chiefly ocean waves. In particular the peak between 0.1 and 0.3 Hz is clearly associated with the interaction of water waves of nearly equal frequencies but opposite directions. At high frequency (above 1 Hz), seismic noise is mainly produced by human activities such as road traffic and industrial work; but there are also natural sources, like rivers. Around 1 Hz, wind
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