With all but the most powerful of hands, you always can justify just calling, rather than raising, when you're in a blind position. Remember that you will be in poor position throughout future rounds of betting (except if you're the big blind against only the small blind). This gives you less of an advantage than it may seem, and makes a raise questionable.
Also, when you're in a blind, it costs you less voluntary money to call than it costs other players. This means you're often getting a good deal to call, based on pot odds (the amount in the pot versus the amount it costs to call). But when you raise, the proportion of the money you've already blinded becomes less significant, and your pot odds diminish. It's hard to justify reducing pot odds with marginally strong hands when you'll have poor position on future betting rounds.
Do this: When you're conspicuously winning and faced with a borderline decision between checking and betting, bet… AND between calling and raising, raise. Most Players who play at Poker Rooms Allowing US Players do this.
But… when you're conspicuously losing and faced with a borderline decision between checking and betting, check… AND between calling and raising, call. These adjustments works like magic, and they're pure profit.
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