(my) Criteria for Sports Classification

First let us list the criteria

Team vs Individual
Quantitative vs Qualitative
Absolute vs Relative
Automatic vs Judgement
External vs Human
Physiology vs Precision
Competition vs Leisure

and now let us explain what we mean

Team vs Individual
Sports where the final "team" result is obtained by addition or combination of the results of individuals are definitely individual sports. Relays and synchronised diving are such sports. Most ball sports are team sports but I would qualify baseball and cricket as sports with a large individual component. What about sports where we have a couple? I would classify such sports as individual. Synchroniseed swimming is a team sport for teams of 8 but an individual one for teams of two. A rule-of-thumb would be: one and two are individual while three or more are team but the first sentence is an absolute rule.
Quantitative vs Qualitative
A quantitative sport is one where the result is some measurable quantity. Typically we can have a time, a length or a mass but also a score (e.g. number of goals) or even the notes attibuted by (human) judges. Climbing a mountain is typically a qualitative achievement, which can be of great value but still qualitative. Other such examples are circumnavigating the world on a sailboat, a difficult cave diving (I am choosing here, on purpose, examples which correspond to exceptional achievements).
Absolute vs Relative
A relative sport is one where the outcome depends on the opponent. A boxing match is definitely a relative sport. Some sports with judges' notation (like figure skating) have a small relative component, in the sense that the judges adjust their marks slightly depending on the participants. In running events the final result may be somewhat influenced by the presence of all the participants but still running is an absolute sport.
Automatic vs Judgement
Automatic refers here to how the result is obtained. If it is given by some measurement that it is automatic (in the sense that it could be automatised). In some sports, like diving, the notes are obtained by the judgement of expert judges. Even if one could think of some expert system, which would attribute the notes in this case, any artificial intelligence treatment looks inefficient for sports like athletic dancing which have a strong artistic component.
External vs Human
The distinction here is on who is furnishing the primal effort. Most sports would be judged as human in the sense that the athlete is the one providing the energy. Car racing is the typical "external" sport. Horse riding has a very strong external component (this does not mean that the rider is not making a considerable effort). In this sense target shooting is an external sport while darts is human.
Physiology vs Precision
Here we are making the distinction based on what counts more. Running is clearly a sport where physiology is the main factor of success. In a sport like bowling the physiological factor is secondary: precision is what conditions the outcome. A strong physiological factor may be present is some precision sports, like archery, but still the later will be classified as a precision discipline.
Competition vs Leisure
Here in most cases we have a question of attitude rather than an inherent property of the sport: in most cases a discipline can be practised both as a leisure and as a competition sport. However some sports can only be leisure ones. Underwater diving is such an example. Leisure does not mean easy: swimming the Channel can be done without any competition spirit but it is still very hard.

A good application of these ideas would be to take a (in fact, the most complete available) list of sports and try to classify each following the criteria above. (to be continued)