Adjusted initial parameters for maximum prediction power; in particular,

[foosball] / foosball.pm

diff --git a/foosball.pm b/foosball.pm
index 4fd318c85b4f2c4d625fef094c9fe6f843aac81a..38722422caea742ec265373305a913c3e342b451 100644 (file)
--- a/foosball.pm
+++ b/foosball.pm
@@ -1,28 +1,53 @@
 use strict;
 use warnings;
 use DBI;
+use POSIX;
 
 package foosball;
 
+our $initial_rating = 1500.0;
+our $initial_rd = 400.0;
+our $c = 22.5;
+
 sub db_connect {
        my $dbh = DBI->connect("dbi:Pg:dbname=foosball;host=127.0.0.1", "foosball", "cleanrun", {AutoCommit => 0});
        $dbh->{RaiseError} = 1;
        return $dbh;
 }
 
+sub round {
+       my $x = shift;
+       return -round(-$x) if ($x < 0.0);
+       return POSIX::floor($x + 0.5);
+}
+
 sub find_single_rating {
        my ($dbh, $username, $limit) = @_;
+       $limit = "" if (!defined($limit));
        my ($age, $rating, $rd) = $dbh->selectrow_array('SELECT EXTRACT(EPOCH FROM (CURRENT_TIMESTAMP-ratetime)), rating, rd FROM single_rating WHERE username=? '.$limit.' ORDER BY ratetime DESC LIMIT 1',
                undef, $username);
        $rd = apply_aging($rd, $age / 86400.0);
+
+       if (!defined($rating)) {
+               $rating = $initial_rating;
+               $rd = $initial_rd;
+       }
+
        return ($rating, $rd);
 }
 
 sub find_double_rating {
        my ($dbh, $username, $limit) = @_;
+       $limit = "" if (!defined($limit));
        my ($age, $rating, $rd) = $dbh->selectrow_array('SELECT EXTRACT(EPOCH FROM (CURRENT_TIMESTAMP-ratetime)), rating, rd FROM double_rating WHERE username=? '.$limit.'ORDER BY ratetime DESC LIMIT 1',
                undef, $username);
        $rd = apply_aging($rd, $age / 86400.0);
+       
+       if (!defined($rating)) {
+               $rating = $initial_rating;
+               $rd = $initial_rd;
+       }
+
        return ($rating, $rd);
 }
 
@@ -33,41 +58,35 @@ sub create_user_if_not_exists {
        return if ($count > 0);
        $dbh->do('INSERT INTO users (username) VALUES (?)',
                undef, $username);
-       $dbh->do('INSERT INTO single_rating (username,ratetime,rating,rd) VALUES (?,CURRENT_TIMESTAMP,1500.0,350.0)',
-               undef, $username);
-       $dbh->do('INSERT INTO double_rating (username,ratetime,rating,rd) VALUES (?,CURRENT_TIMESTAMP,1500.0,350.0)',
-               undef, $username);
+       $dbh->do('INSERT INTO single_rating (username,ratetime,rating,rd) VALUES (?,CURRENT_TIMESTAMP,?,?)',
+               undef, $username, $initial_rating, $initial_rd);
+       $dbh->do('INSERT INTO double_rating (username,ratetime,rating,rd) VALUES (?,CURRENT_TIMESTAMP,?,?)',
+               undef, $username, $initial_rating, $initial_rd);
        return $dbh;
 }
 
-# 10-9 is 0.60
-# 10-0 is 1.00
-sub find_score {
-       my ($score1, $score2) = @_;
-       if ($score1 == 10) {
-               # yay, a win
-               return 0.60 + 0.40 * (9.0-$score2)/9.0;
-       }
-       if ($score2 == 10) {
-               # a loss
-               return 0.40 - 0.40 * (9.0-$score1)/9.0;
-       }
-       die "Nobody won?";
-}
-
-# c=8 => RD=50 moves to RD=350 over approx. five years
-our $c = 8;
-
+# $age is in days
 sub apply_aging {
        my ($rd, $age) = @_;
-       $rd = sqrt($rd*$rd + $c * $c * ($age / 86400.0));
-       $rd = 350.0 if ($rd > 350.0);
+       $rd = sqrt($rd*$rd + $c * $c * $age);
+       $rd = $initial_rd if ($rd > $initial_rd);
        return $rd;
 }
 
 sub calc_rating {
        my ($rating1, $rd1, $rating2, $rd2, $score1, $score2) = @_;
-       my $result = `/srv/foosball.sesse.net/foorank $rating1 $rd1 $rating2 $rd2 $score1 $score2`;
+       my $result = `/srv/foosball.sesse.net/foosrank $rating1 $rd1 $rating2 $rd2 $score1 $score2`;
+       chomp $result;
+       my ($newr1, $newrd1, $likelihood) = split / /, $result;
+
+       $newrd1 = 30.0 if ($newrd1 < 30.0);
+
+       return ($newr1, $newrd1, $likelihood);
+}
+
+sub calc_rating_double {
+       my ($rating1, $rd1, $rating2, $rd2, $rating3, $rd3, $rating4, $rd4, $score1, $score2) = @_;
+       my $result = `/srv/foosball.sesse.net/foosrank $rating1 $rd1 $rating2 $rd2 $rating3 $rd3 $rating4 $rd4 $score1 $score2`;
        chomp $result;
        my ($newr1, $newrd1) = split / /, $result;
 
@@ -76,4 +95,5 @@ sub calc_rating {
        return ($newr1, $newrd1);
 }
 
+
 1;