<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=US-ASCII" http-equiv=Content-Type> <META name=GENERATOR content="MSHTML 11.00.9600.18538"></HEAD> <BODY id=role_body style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; COLOR: #000000" bottomMargin=7 leftMargin=7 rightMargin=7 topMargin=7><FONT id=role_document color=#000000 size=2 face=Arial> <DIV>I certainly remember this formula -- using it, even -- but I forgot the values for "m" and "b" a long time ago. And it didn't turn up in a search through a few things. However, that formula was devised (I think by Rick Hutchinson or by one of Rick's "assistants") way back when Old Faithful's average was somewhere in the 70-minute range. Therfore, I've got to believe that the values for those constants have changed a great deal.</DIV> <DIV> </DIV> <DIV>T. Scott Bryan</DIV> <DIV> </DIV> <DIV> <DIV>In a message dated 12/29/2016 7:15:52 A.M. US Mountain Standard Time, jeff.cross@utah.edu writes:</DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT style="BACKGROUND-COLOR: transparent" color=#000000 size=2 face=Arial>Years ago, someone reported a formula of the form y = mx + b for predicting Old Faithful.<BR><BR>Y is the interval<BR>X is the duration<BR><BR>How has this formula changed from one year to the next?<BR><BR>Specifically, are the current values of m and b what they always were?  Larger?  Smaller?<BR><BR>Jeff Cross<BR>jeff.cross@utah.edu</FONT></BLOCKQUOTE></DIV></FONT></BODY></HTML>