An <a href="search.pl?p=S-shaped curve">S-shaped curve</a> or S-curve. Curves describing the growth of the number of adopters of an innovation. The elongated S-shape grows from near zero to approach the <a href="search.pl?p=saturation level">saturation level</a> over time.&nbsp; The equation of the <a href="search.pl?p=logistic">logistic</a> process is an example. Meade and Islam (2001) discuss the use of such curves in forecasting.<o:p></o:p></P>
 <ul>
   <li>Meade, N. &amp; T. Islam (2001), “Forecasting the 
diffusion of innovations: Implications for time-series extrapolation,” in J. S. 
Armstrong (ed.), <I>Principles of Forecasting</I>. Norwell, MA: Kluwer Academic 
Press.</li>
 </ul>