System Questions

[Guest przeszczepan]

Hello Everyone, I've not posted for a while( got admitted to the Warsaw School of Economics, had fantastic holidays with my girlfriend for money earned on betting, and produced a loosing system in the meantime). Now I'm back and enthusiastic about flooding the forum with loads of rookie's questions about rating systems. 1. What would you call a sufficient set of data to develop a system? 5000 games? 10000? Or maybe 2500 would suffice? 2. Would you increase the size of the data by including lower leagues from the particular country? 3. What's the smallest recommended size of data for backtesting? 4. During a backtesting on last three seasons a system proved successful. Would you add the results from these 3 seasons to the system? After all, they seem to have a similar distribution of probabilities per each outcome( because they produced a profit

[Guest przeszczepan]

? this is the continuation. I've no idea why it did not appear in the previous post. It didn't even looked like I could edit it since I got logged out:rolleyes it's only a guess). Or maybe taking only the first two into account and leaving the most previous one for another backtesting would be more reasonable? 5. In the "Rating Systems for Fixed Odds..."( www.football-data.co.uk/ratings.pdf ) talking about best fit lines for different charts Joe says that some or other equation describes real data in the best way. How do I check this? Should I try out all kinds of equations and see which R^2 is the closest to 1 or maybe only the simpliest lines are advisable? 6. After assigning the best fit lines for all outcomes, on the page 6 there is a table with result expectancies. In the column"total" there is 100% in each line. How does it happen? As far as I remember, when I was developing my lousy system, the probabilities counted with the equations did not add up. I hope it makes any sense. Believe me, writing in a foreign language about ratings systems for fixed odds football match prediction is far from easy. Unfortunately, the level of betting forums in Polish is... uh not the highest:( That's probably why after one year's betting I have no idea what's the word for "odds" in my language.