hi everyone,

i think my idea is not very new and may have been done before a 100 times.
i backtested a trend i noticed on several tournaments.
my hypothesis is that a qualifier for the general tournament has better chances for an upset or to succeed.
for that i tracked 6000 matches from the last 2,5 years of the ATP and WTA.
i wanted to create an edge where i can develop a category for success of qualifiers once they reach the main tournament.

my reasons for this thesis:

- qualifiers are familiar with court and circumstances like weather, time zone etc.

- they have a positive mindset entering the game, knowing that they have won several games before and reached the main goal of entering the tournament

- being a qualifier does not mean that the player is a weak one. maybe he/she has been injured or tries a comeback

negative aspects:

- motivation and confidence will not help a qualifier when he or she plays the nadal in paris in the first round. so we have to create selection criteria based on odds offered.

- fatigue will play a bigger role once the qualifier advances a few rounds.

so taking these aspects into account i started with backing every qualifiers match even if it would be hopeless.

The period of analysis started 1.1.2011 and extends to 3.3.2013.
ATP and WTA generated 5897 matches from which 2132 qualified for backtesting.
Without any tweak, taking every Qualifiers match would have a record of:

General Results:
818 Won
1314 Lost
SR: 38,37%
Profit (with Pinnacleodds from tennis data co uk): 71,53
Yield: 3,36%

I was not happy with the results and i tried to look for sharper and more successful margins.
The best results i got:

ATP Qualifiers:
Rule: Odd of Qualifier under 6,5
414 Won
532 Lost
SR: 43,76%
Profit: 81,66
Yield: 8,63%

WTA Qualifiers:
Rule: Odd of Qualifier must be under 12,5 and only matches in the first two rounds of the tournament.
352 Won
506 Lost
SR: 41,03%
Profit: 70,21
Yield: 8,18%

Two System Combined Results in two years and three months:
766 Won
1038 Lost
SR: 42,46%
Profit: 151,87
Yield: 8,42%

and this only with Pinnacle odds. If you take the maximum odds from tennis data co uk, the results are tempting.
Profit with maximum odds: 263,67
Yield: 14,62%