Difference in strategies with stakes?

What difference in strategies should occur as the stakes change. For example in a tournament(888.com| 24x7 Freerolls) , I have noticed that I have decent rank in the initial stage when the stakes are low but as the stakes increase my rank starts declining. I have also considered the effect that high stakes lead to greater pot size.
Also I have noticed an increase in bluffing as the stakes go up. Is it just my perception?

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What do you understand by "rank"? – Bogdan Apr 7 '13 at 10:18
place in the tournament based on amount of chips – Abhishek Bhatia Apr 7 '13 at 10:19
Stack size and blinds' size play a major role in your gameplay especially in tournament games. I suggest reading stack size strategy and the blinds will help you in your game. – Theo Apr 7 '13 at 15:09
I think when you say stakes you mean blinds, the stakes for the tournament are always the same, its the buy in, in this case nothing – hmmmm Apr 7 '13 at 17:49
@hmmmm yes that is exactly what I meant – Abhishek Bhatia Apr 7 '13 at 19:00

At first, rank, as you define it, has nothing to do with the stages of a tournament. It has to do with a thing, called the M factor. M represents the number of orbits that you will survive if you never play a hand, if you fold immediately, when your chance is given. Its formula is:

M=(Stack size)/(big blind+small blind+total antes)

(you should add one ante per player at the table)

How does M affect how you play? The larger the M is, the closer to "normal poker" you play, because you have lots of space for maneuvers. The smaller M you have, the closer to mechanical poker you will play. When M is low enough (5 or less), you have a simple problem: push or fold preflop.

From this theory, as long as the M decreases, the play will, until a point, become looser because there are bigger pots to be won and you need to win to survive. This is probably why you think that there is a lot of bluffing. It may be, but surely there is a strategy behind it.

The reason for your position declines while advancing the tournament is that you probably keep playing tight for longer than necessary. The others gather pots, you don't.

One last thing: you mentioned the 24x7 freerolls. As this is a freeroll, expect the play to be more chaotic, because there isn't any stakes for people to care. But when you play tournaments with buy-in of at least 1\$, people apply some theory.

Hope it helps, Good luck!

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how to determine the perfect time to start playing loose – Abhishek Bhatia Apr 7 '13 at 19:02
Only through experience and reading tournament theory. – Bogdan Apr 8 '13 at 5:05