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3 html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
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5 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" xmlns:t="http://template.sesse.net/">
7 <title>Foosball!</title>
8 <link rev="made" href="mailto:sgunderson@bigfoot.com" />
9 <meta name="MSSmartTagsPreventParsing" content="TRUE" />
14 <h2>Add a singles result</h2>
16 <form method="post" action="add-single-result.pl">
20 <td><input name="username1" value="" size="10" /></td>
24 <td><input name="username2" value="" size="10" /></td>
29 <input name="score1" value="" size="2" /> -
30 <input name="score2" value="" size="2" />
34 <td colspan="2"><input type="submit" /></td>
39 <h2>Add a doubles result</h2>
41 <form method="post" action="add-double-result.pl">
44 <th>Team 1 (usernames)</th>
46 <input name="team1_username1" value="" size="10" /> and
47 <input name="team1_username2" value="" size="10" />
51 <th>Team 2 (usernames)</th>
53 <input name="team2_username1" value="" size="10" /> and
54 <input name="team2_username2" value="" size="10" />
60 <input name="score1" value="" size="2" /> -
61 <input name="score2" value="" size="2" />
65 <td colspan="2"><input type="submit" /></td>
70 <h2>Singles score board</h2>
82 <tbody t:id="singletop">
84 <td><t:username /></td>
87 <td><t:lowerbound /></td>
93 <h2>Doubles score board</h2>
105 <tbody t:id="doubletop">
107 <td><t:username /></td>
108 <td><t:rating /></td>
110 <td><t:lowerbound /></td>
116 <h2>Last ten games</h2>
123 <th colspan="2">Opponents</th>
125 <th colspan="2">Rating diff.</th>
128 <tbody t:id="lastgames">
130 <td><t:gametime /></td>
132 <td><t:username1 /></td>
133 <td><t:username2 /></td>
134 <td><t:score1 /> – <t:score2 /></td>
141 <h2>Assess a singles match</h2>
143 <form method="post" action="assess-single.pl">
147 <td><input name="username1" value="" size="10" /></td>
151 <td><input name="username2" value="" size="10" /></td>
154 <td colspan="2"><input type="submit" /></td>
160 <h2>About the ratings</h2>
162 <p>The rating system in use is called <em>FoosRank</em>, and is specially
163 designed for this site. It is a Bayesian rating system, inspired by
164 <a href="http://math.bu.edu/people/mg/glicko/">Glicko</a> but re-worked
165 out from scratch with a statistically sound model of non-binary results,
166 and adjusted for teams (with some ideas from Microsoft's TrueSkill
167 system). For those not familiar with Bayesian ratings, the most important
171 <li>Your rating is a <em>statistical estimation</em> of your true skill.
172 It has a mean (the point estimate of your skill) and a deviation
173 (measuring the uncertainity of the estimate), called the RD. It is approximately
175 <li>When you win or lose a game, your rating will change accordingly,
176 based on your score and your opponent. <em>You do not get 'points'
177 for winning or losing, the estimate is merely getting more accurate.</em>
178 In the process, the RD gets lower as you play. However, the RD increases
179 with time, opening up for the fact that your true skill can change.
180 (Glicko 2 also supports a volatility measure, which better models change
181 in true skill, but it has not been implemented here.)</li>
182 <li>The score board is sorted by a conservative estimate of your rating
183 (mean - 3 * RD). This makes it non-attractive for people with artifically
184 high ratings (especially newcomers) to avoid playing to stay high up in
185 the score board.</li>
186 <li>The single and double rankings are separate. Even though you play as a
187 team and all four players' rankings and RDs influence the rating adjustment,
188 you are ranked as an individual, as we do not usually play with fixed
192 <p>For the more technically minded, a
193 <a href="http://home.samfundet.no/~sesse/foosrank.pdf">very rough writeup
194 on the mathematics behind FoosRank</a> is available in PDF format. It is,
195 however, by no means finished.</p>