I suppose when wagering (risking) the same amount per play.
Yeah, and filling at different levels can be tricky to make sure risk amounts are appropriate, for stability.
But I do want to say something about changing your bet size. It always changes your breakeven point, and often not for the better. And, for example, betting a "flat percentage" of a roll each bet is costly.
Here's an adaptaion of something I posted in the past...
...I’ve posted over and over again that changing you bet size is equivalent to progressive betting and it is costly.
Let’s keep it simple and get back to basics. Take a set of 21 bets; give yourself 11 wins and 10 losses. Now take any starting bankroll amount. To keep it simple, bet 5.5% to win 5% for each bet and put the wins and losses in any order you desire. After each bet, win or lose, adjust the next bet to 5.5% of the new bankroll. Many bettors use this form of money management.
Now, if you didn’t change the size of your bets, 52.4%, or 11 wins and 10 losses would result in breaking even.
But this progressive scheme requires changing the size of your bets after each play, changing the breakeven point. How much it changes depends on the percentage bet, but the higher the percentage, the worse off you are. With my example, of 5.5%, the breakeven point nears 54%.
Bettors should be thankful for discount books and vigorish, as this strategy raises their breakeven point, which was offset by the reduced vig.
Again, the percentage doesn’t matter; it’s easier to use 5.5% for this exercise but with other perentages, the results are along the same lines.
Try it again and again. No matter what order you place your 11 wins and 10 losses, after those 21 bets, you always have 97.1% of your roll left.
In fact, after 110 wins and 100 losses with 5.5% bet each time, you would be down somewhere in the neighborhood of 25% of your starting bankroll...
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I wrote that some time back at SBR in response to a poster's suggestion.
Any change in bet size will mess with your breakeven point. Yes, with a good edge, there are many who bet a partial Kelly system and do well, but anyone betting Full Kelly with get likely get killed, unless all bets are +103 to -103, lol. Kelly betting is a percentage of roll, and a progressive strategy.
If a bettor has a losing streak, then he inevitably bets less. Then he has the winning streak and hits his breakeven point but beause the wins were less risk, and the cost of vig, that bettor doesn't have the money he deserves. If he goes on a winning streak, and then increases his bet, here comes the losing the streak and at breakeven, again he is behind in money.
This isn't bad timing. These are predictable results within the probabilies. It's bad money management.