When to call all-in in heads-up game?
if I've a A/4, and my opponent raise all-in, is a good idea call?
PS: I have the same amount of chips than my opponent.
When to call all-in in heads-up game?
if I've a A/4, and my opponent raise all-in, is a good idea call?
PS: I have the same amount of chips than my opponent.
You haven't provided enough information. This is entirely dependent on what the action was leading to the all-in, current stack sizes, and the frequency with which your opponent is taking said action. I can tell you, just from experience, that your opponent would either need to be very short stacked, ~13-15BB or less, or jamming all-in with a very wide range, ~40%+ of hands, for you to call off with A4.
Regardless, you should learn to use a program like ICMIZER or CREV which will enable you to come up with maximally exploitative calling ranges based on the current variables. Here's an example:
You're playing a $30 heads-up hyper-turbo on PokerStars. You both start with $500 chips and the blinds are $10/$20, giving you a 25BB stack. Villian is the small blind and also has the button. You're the big blind.
Villian jams all-in on the first hand. You have A4o. What do you do? You fold. Villian would need to be jamming here with 42.08% of hands to justify calling with A4o. As such, you can't call off this wide until you gain reads that Villian is jamming a maniacal range. This is even more important as stacks get deeper.
Villian Jamming Range (42.08% of hands)
Hero's Maximally Exploitative Calling Range (22.17% of hands)
The numbers below each hand are the expected value, or EV, of calling with each hand, using percentages of the prize pool as the unit of measurement.