The CADE-17 ATP System Competition

Design and Organization

This document contains information about the:

The design and procedures of CASC-17 evolved from those of CASC-13, CASC-14, CASC-15, and CASC-16. Important changes since CASC-16 are:

The rules, deadlines, and specifications given here, are absolute. Only the competition panel has the right to make exceptions.

Disclaimer

Every effort has been made to organize the competition in a fair and constructive manner. No responsibility will be taken if, for one reason or the other, your system does not win.

Divisions

CASC-17 is divided into divisions according to problem and system characteristics. There are five competition divisions in which the systems are explicitly ranked, and one demonstration division in which systems can demonstrate their abilities without being formally ranked.

Competition Divisions

The Problems section explains what problems are eligible for use in each division and category.

Entry into the competition divisions is subject to the following rules:

Demonstration Division

ATP systems that cannot run on the general hardware, or cannot be entered into the competition divisions for any other reason, can be entered into the demonstration division. demonstration division systems can run on the general hardware, or the hardware can be supplied by the entrant. The entry specifies which competition divisions' problems are to be used. The results will be presented along with the competition divisions' results, but may not be comparable with those results.

Infrastructure

Hardware and Software

The competition will be run on SUN workstations. Details are yet to be confirmed.

Problems

Problem Selection
The problems will be selected from the TPTP Problem Library, v2.3.0 or a patch thereof. The problems have to meet certain criteria to be eligible for selection: The problems used will be randomly selected from the eligible problems at the start of the competition, based on a seed supplied by the competition panel.

Number of Problems
The minimal numbers of problems that have to be used in each division and category, to ensure sufficient confidence in the competition results, will be determined from the numbers of eligible problems in each division and category (the competition organizers have to ensure that there is sufficient CPU time available to run the ATP systems on this minimal number of problems). This minimal numbers of problems will then be used in determining the time limit imposed on each solution attempt.

A lower bound on the total number of problems that will be used will be determined from the number of workstations available, the time allocated to the competition, the number of ATP systems to be run on the general hardware over all the divisions, and the time limit, according to the following relationship: 

                     Number of workstations * Time allocated
Number of problems = ---------------------------------------
                        Number of ATP systems * Time limit
It is a lower bound on the total number of problems because it assumes that every system will use all the time limit for each problem. Since some solution attempts will obviously succeed before the time limit is reached, more problems can actually be used. The actual numbers used in each division and category will be determined according to the judgement of the competition organizers.

Problem Preparation
It is necessary to ensure that no system receives an advantage or disadvantage due to the specific presentation of the problems in the TPTP. To this end the tptp2X utility, distributed with the TPTP, will be used to:

Further, to prevent systems from recognizing problems from their file names, symbolic links will be made to the selected problems, using names of the form CCCNNN-1.p for the symbolic links, with NNN running from 001 to the number of problems in the respective division or category. The problems will be specified to the ATP systems using the symbolic link names.

In the demonstration division the same problems will be used as for the competition divisions, with the same tptp2X transformations applied. However, the original file names will be retained.

Time Limits and Timing

A time limit will be imposed on each solution attempt. On the general hardware a CPU time limit will be imposed, while in the demonstration division the entrant can choose to use either a CPU or a wall clock time limit.

A minimal time limit of 180 seconds will be used. The maximal time limit will be determined using the relationship used for determining the number of problems, with the minimal number of problems as the "Number of problems". The time limit will be chosen as a reasonable value within the range allowed.

The timing will be done by the UNIX /bin/time command, which returns times in units of 0.1 second. If an ATP system cannot solve a problem, the runtime will be set to the time limit.

In the competition divisions a wall clock time limit will be imposed in addition to the CPU time limit, to prevent very high memory usage that causes swapping. The wall clock time limit will be double the CPU time limit.

Entry Requirements and Procedures

To be entered into CASC-17, systems must be registered using the CASC-17 system registration form. No registrations will be accepted after the registration deadline. For each system entered, a person has to be nominated to handle all issues (including execution difficulties) arising before and during the competition. The nominated entrant must formally register for CASC-17, using the CADE-17 registration form. However, it is not necessary for entrants to physically attend the competition.

Entering many similar versions of the same system is deprecated. Entrants may be required to limit the number of system versions that they enter. The division winners from CASC-16 will automatically be entered into their division, to provide benchmarks against which progress can be judged. After the competition all systems' source code will be made publically available on the CASC-17 WWW site.

The precomputation and storage of any information for individual TPTP problems for usage during the competition is contrary to the spirit of the competition, and is not allowed. The precomputation and storage of information that is reasonably likely to be useful in some future application is permitted. For every problem solved, the system's solution process has to be reproducible by running the system again.

It is assumed that each entrant has read all the WWW pages related to the competition, and has complied with the competition rules. Non-compliance with the rules could lead to disqualification. A "catch-all" rule is used to deal with any unforseen circumstances: No cheating is allowed. The panel is allowed to disqualify entrants due to unfairness and to adjust the competition rules in case of misuse.

System Description

A system description has to be provided for each ATP system entered. The system descriptions, along with information regarding the competition design and procedures, will form the proceedings for the competition. The system descriptions must fit onto a single A4 page, using this HTML schema. The schema has the following sections:

You must email the system description to the competition organizers before the registration deadline.

System Properties

Entrants have to ensure that their systems execute in the competition environment, according to the checks listed below. Entrants are advised to perform these checks well in advance of the installation period. This gives the competition organizers time to help resolve any difficulties encountered.

The ATP systems have to be executable by a single command line, using an absolute path to the executable that may not be in the current directory. The command line arguments are the absolute path name for a symbolic link as the problem file name, the time limit (if required by the entrant), and entrant specified system switches (the same for all problems). No shell features, such as input or output redirection, may be used in the command line.

The ATP systems that run on the general hardware have to be interruptable by a SIGXCPU signal, so that the CPU time limit can be imposed on each solution attempt. The default action on receiving this signal is to exit (thus complying with the time limit, as required), but systems may catch the signal and exit of their own accord. Both approaches are acceptable for the competition. If a system runs past the time limit this is noticed in the timing data and the system is considered to have not solved that problem. Wall clock time limits are imposed using SIGALRM. When terminating of their own accord, the ATP systems have to output a distinguished string (specified by the entrant) to stdout indicating the result: The ATP systems are not required to output solutions (proofs or models). However, systems that do output solutions to stdout will be highlighted in the presentation of results. For practical reasons excessive output from the ATP systems is not allowed. A limit, dependent on the disk space available, will be imposed on the amount of stdout and stderr output that can be produced. The limit will be at least 10KB per problem (averaged over all problems so that it is possible to produce some long proofs).

If an ATP system terminates of its own accord, it may not leave any temporary or other output files. If an ATP system is terminated by a SIGXCPU or SIGALRM, it may not leave any temporary or other output files anywhere other than in /tmp.

The CPU time taken by the ATP systems on the general hardware must be measurable by the UNIX /bin/time command.

System Installation

Access to the general hardware (or equivalent) will be made available from the 29th May 2000. Entrants must install their systems on the general hardware, and ensure that their systems execute on the general hardware according to the required system properties.

For systems entered in the competition divisions, entrants must deliver an installation package to the competition organizers by 11th June 2000. The installation package must be a .tar.gz file containing the system source code, any other files required for installation, and a ReadMe file with instructions for installation. The installation procedure may require changing path variables, invoking make or something similar, etc, but nothing unreasonably complicated. All system binaries must be created in the installation process; they cannot be delivered as part of the installation package. The system will be reinstalled onto the general hardware by the competition organizers, following the instructions in the ReadMe file. Installation failures before the installation deadline will be passed back to the entrant. After the installation deadline access to the general hardware will be denied, and no further changes or late systems will be accepted (i.e., deliver your installation package before the installation deadline so if the installation fails you have a chance to fix it!). If you are in doubt about your installation package or procedure, please email the competition organizers.

After the installation deadline the organizers will test the ATP systems, first to check that the systems execute correctly (according to the above checks), and secondly to check for soundness. For the soundness testing, non-theorems (satisfiable variants of the eligible problems, e.g., without the conjecture clause, and satisfiable problems selected from the TPTP) will be submitted to the systems participating in the MIX, UEQ, FOF, and SEM divisions, and theorems (selected from the TPTP) will be submitted to the systems participating in the SAT division. Finding a proof of a non-theorem or a model for a theorem indicates that the system is unsound. If an ATP system fails the soundness testing it is disqualified. The soundness testing has a secondary aim of eliminating the possibility of an ATP system simply delaying for some amount of time and then claiming to have found a solution. Further soundness testing will be performed after the competition, as described in the section on performance evaluation.

In the demonstration division the systems will be installed on the respective hardware by the entrants, and no soundness testing needs to be performed.

System Execution

Execution of the ATP systems on the general hardware will be controlled by a perl script, provided by the competition organizers. The jobs will be queued onto the workstations so that each workstation is running one job at a time. All attempts at the Nth problems in all the divisions and categories will be started before any attempts at the (N+1)th problems.

During the competition a perl script will parse the systems' output. If an ATP system's success string is found then the timing information from the time command will be extracted. The CPU time taken, or the time limit if no solution was found, will be recorded. This data will be used to generate an HTML-file, and a WWW-browser will be used to display the results.

The execution of the demonstration division systems will be supervised by their entrants.

Performance Evaluation

The systems will be ranked within each competition division and category according to the number of problems solved. If several systems solve the same number of problems, then those systems will be ranked according to their average runtimes over solutions found. If any division is won by the system that won that division in the previous CASC, then no winner will be announced in that division. Otherwise winners will be announced in each division and category, and prizes will be awarded.

If only one ATP system registers for a particular competition division, no winner can be announced for that division, but the results for that system will still be presented.

At some time after the competition, all high ranking systems in each division will be tested over the entire TPTP. This testing will provide a final check for soundness, and any system found to be unsound will be retrospectively disqualified.