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Information for Event Directors

This page explains how to become an event director and submit events to Ratings Central.

Rating Scale

In order to be a Ratings Central event director and submit events to Ratings Central, you must have an understanding of the rating scale that Ratings Central uses. In other words, you must know what it means to be a “1500 player” or a “2000 player”, and you must be able to watch a player playing a match and estimate their level to within a few hundred rating points. To assist you in understanding the rating scale, we have provided some videos that you can watch. Also, see the discussion of how the Ratings Central rating scale relates to the USATT rating scale on the Priors for Unrated Players page.

Submitting Events

There are four ways to submit events to Ratings Central. You can use Cantor, Zermelo, Gerard McCarthy’s RCPennantSubmitter, or your own software.

Both Cantor and Zermelo are Windows apps that you run on your own PC. (There is no Web form for submitting events becase Cantor is much easier to use than a Web form.) System requirements are any computer running Windows 10, 8.1, 8, 7, Vista, or XP. If you have a Mac or Linux, you’ll need Wine or CrossOver. For Zermelo, you’ll need a printer and your screen resolution must be at least 800 pixels wide by 600 pixels high.

To submit events, you will also need an Internet connection. You do not need to be connected to the Internet while the matches are being played, but you will need to be connected when you are ready to submit results to Ratings Central.

Cantor’s sole purpose is to let you record results and submit them to Ratings Central. Cantor can be used with any event that you run, regardless of its format.

Zermelo’s purpose is to make running table tennis tournaments simple. Zermelo is the premiere software application for running table tennis tournaments. It handles all aspects of running a tournament, including submitting the results to Ratings Central. Zermelo also has support for running USATT-sanctioned tournaments. While Zermelo can handle most of the popular tournament formats, it cannot handle all formats. Cantor is easier to learn than Zermelo is because it does less.

For more information on Cantor and Zermelo, please download and run the setup programs. Each setup program installs the application and the user’s manual. You can also download the user’s manuals separately, if you want to look at them without installing the applications. You need to have the free Adobe Reader or a similar program installed to view the manuals.

Gerard McCarthy’s RCPennantSubmitter is designed to submit pennant scores to Ratings Central. It also does pennant fixturing and ladders.

If you have been using your own software to run your event, please to find out how you can interface your software to Ratings Central.



If you have a previous version of Cantor or Zermelo installed, you do not need to uninstall it before installing the current version.

Registering as an Event Director

Before you can submit any events to Ratings Central, you must register as an event director. To do this, click the “Register as an Event Director” link at the bottom of this page and fill out the form. We will let you know via email (typically within one day) when we have activated your account.

Once we activate your account, you will be able to use Cantor and Zermelo to submit results. You will also be able to use the Ratings Central website to download a rating list (that includes player postal and email addresses), download a club list, update your director information, add or modify club information, update player information, and associate players, directors, and events with your clubs. To do any of these things, simply log in by entering your director ID number and password in the “Event Director Login” form that is on every page in the left sidebar under the ads. When you are ready to run an event, you will want to download a rating list and a club list for importing into Cantor or Zermelo.

Note that you do not need to register as a Ratings Central event director if all you want to do is use Zermelo for an event that you will not be submitting to Ratings Central.

Event directors are responsible for making corrections (including removing duplicate players) for any events that they submit. Such corrections may be necessary long after an event is submitted. Therefore event directors are expected to back up their database files and retain them indefinitely.

Event Minimum Requirements

It is up to you what events you submit, but here are the minimum requirements:

  • The event must have some sort of definite structure, for example, round robin, single or double elimination, team match, league match, ladder, winner stays. In other words, it must be more than just getting a bunch of players together and having each play whomever they wish. In particular, two players going to the club and playing each other half a dozen times is not an acceptable event.
  • You must submit all matches that are part of the event, not just some of them.
  • The event must be open to some segment of the public, for example, anyone who pays the entry fee, club members, students at your school. In other words, more than just your friends.
  • The event must be publicized in some way, for example, mailing or emailing entry forms, posting a notice on a club website, handing out fliers, posting a notice in your club.
  • You must do your best to collect accurate information (name, sex, country) on each new player and to correct any errors in such information for existing players.

You do not have to use Ratings Central ratings for seeding or eligibility, but of course, you are welcome to.

Unrated Players

Before running an event, please read about assigning priors for unrated players. This explains how (and when) you should specify means and standard deviations for unrated players who play in your events. Besides being available by clicking the link, this information is also in the Cantor and Zermelo user’s manuals.


There is no charge to become a table tennis event director, submit table tennis events, or use Cantor for this purpose. If you are involved in a sport other than table tennis, please so that we may discuss your particular situation.

Zermelo may be used to run almost any table tennis tournament, not just tournaments that you submit to Ratings Central:

  • If you use Zermelo to run a tournament that you submit to Ratings Central, then Zermelo is free to use. This is true regardless of whether you submit your tournament to some other organization in addition to submitting it to Ratings Central.
  • If you use Zermelo to run a tournament that you do not submit to Ratings Central, then the cost to use Zermelo is US$20 per tournament. You may send the money to using Dwolla, PayPal, or whatever method your bank provides to send money to an email address. Or, you may postal mail a check or money order to David Marcus; 25 Beacon St. Apt. 16; Somerville, MA 02143-4336; USA. Or, you may use a credit card, debit card, PayPal, or non-U.S. currency by clicking this button:
    Satisfaction is guaranteed: If, at the end of your tournament, you are not satisfied with Zermelo, simply do not pay for it.

Registration Link

If you would like to receive an email the minute that an event that you played in is processed, please give your event director your email address or your email address. Please include your Ratings Central ID number, if you know it.