Contraction - Revision history

MOmran at 10:21, 17 October 2013

2013-10-17T10:21:39Z

Editor at 16:55, 28 June 2013

2013-06-28T16:55:02Z

Editor at 16:54, 28 June 2013

2013-06-28T16:54:41Z

Editor: /* Basic contraction (c0) */

2013-06-28T16:54:12Z

‎Basic contraction (c0)

MClerc: Created page with "TO COMPLETE == Basic contraction (c0) == The new test position is the gravity centre of the three points defined during the selection phase."

2013-06-12T20:00:57Z

Created page with "TO COMPLETE == Basic contraction (c0) == The new test position is the gravity centre of the three points defined during the selection phase."

New page

TO COMPLETE

== Basic contraction (c0) ==

The new test position is the gravity centre of the three points defined during the selection phase.

@@ Line 2: / Line 2: @@
 We combine four individuals, $x_{best}$, $x_{worst2}$, $w_{worst}$, and the current $x_i$ that has to be moved.<br />
-The idea is that the gravity centre of the three first points may be interesting. However, this move is not applied on all dimensions, but only on some of them, according to the probability estimated at the end of the selection phase. So, finally, the formulae to define the new point $x_e$ are, for each dimension $d$:<br />
+The idea is that the gravity centre of the three first points may be interesting. However, this move is not applied on all dimensions, but only on some of them, according to the probability estimated at the end of the selection phase. So, finally, the formulae to define the new point $x_c$ are, for each dimension $d$:<br />
-if $rand(0,1)<p)$ <br />
+if ($rand(0,1)<p)$ <br />
 $  x_{c,d}=(x_{best,d}+w_{worst2,d}+w_{worst,d})/3$<br />
 else <br />

← Older revision		Revision as of 16:55, 28 June 2013
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−	T== Basic contraction (c0) ==	+	== Basic contraction (c0) ==
	We combine four individuals, $x_{best}$, $x_{worst2}$, $w_{worst}$, and the current $x_i$ that has to be moved.<br />		We combine four individuals, $x_{best}$, $x_{worst2}$, $w_{worst}$, and the current $x_i$ that has to be moved.<br />

@@ Line 1: / Line 1: @@
-TO COMPLETE
+T== Basic contraction (c0) ==
-−
 == Basic contraction (c0) ==
 We combine four individuals, $x_{best}$, $x_{worst2}$, $w_{worst}$, and the current $x_i$ that has to be moved.<br />

← Older revision		Revision as of 16:54, 28 June 2013
Line 2:		Line 2:

	== Basic contraction (c0) ==		== Basic contraction (c0) ==
		+	We combine four individuals, $x_{best}$, $x_{worst2}$, $w_{worst}$, and the current $x_i$ that has to be moved.<br />

−	The ~~new test position~~ is the gravity centre of the three points ~~defined during~~ the selection phase.	+	The idea is that the gravity centre of the three first points may be interesting. However, this move is not applied on all dimensions, but only on some of them, according to the probability estimated at the end of the selection phase. So, finally, the formulae to define the new point $x_e$ are, for each dimension $d$:<br />
		+	if $rand(0,1)<p)$ <br />
		+	$ x_{c,d}=(x_{best,d}+w_{worst2,d}+w_{worst,d})/3$<br />
		+	else <br />
		+	$ x_{c,d}=x_{i,d}$
		+
		+	If $x_{c}$ is better than $x_i$, decrease the population cost
		+	$$ C\leftarrow C-f(x_i)+f(x_c)$$
		+
		+	If $x_{c}$ is better than the best ever found (i.e. $Best$), set $Best=x_{c}$.