dblref explains it above. After the opening tip, the teams just alternate everytime there's a held ball.

Response to irunlikeagirl
 

The alternating possession arrow has improved the game immensely at all levels of play. It speeds up the game at the lower levels where there is an abundance of held ball calls and makes the game fairer in that the toss is generally the weakest skill of officials in general. Bad tosses are often not blown down( for whatever reason)and attempted again and this often results in a critical advantage to the team that gets the ball as a direct result of a bad toss. I am surprised that FIBA has not gone to the arrow. As for the NBA,I guess they feel it adds to the "show" aspect of that venue. Also at the NBA you rarely see the jump ball because of the skill and strengh of the players.
Pistol

Re: Response to irunlikeagirl
 

Pistol,
Why would that be? Why wouldn't it be same level = same strength?
My guess is they just give a little more time for the players to sort it out and call fouls before they call the "jump".
mick

Response top Mick
 

Mick
I think you might be right ! Officials at the higher levels appear to have a better feel of when and when not to call the jump ball -but I don't think they "bail out"on the call by blowing an unnecessary foul,do you?
Pistol

Re: Response top Mick
 

Pistol,
Nah, those guys don't bail out on anything, unless they are told to do so <small>and I'll never be privy to that scoop</small>. I think they just give the players lots of leeway to determine who wants the ball more.
From my seat in TV land, I sure can't tell if the tie-up is a foul, or not; but, it seems like they call more fouls on those intimate plays than "jump balls".
mick

Top Level Held Ball situations
 

Right On !!!
Pistol

Re: Re: Response to irunlikeagirl
 

Think about most of the held balls that you whistle. They usually occur during sloppy play. A mad scramble for a loose ball or some such. Not many of those occur in the NBA. Watch a half dozen NBA games and you probably won't see more than 1 or 2 held balls in all 6 games combined.

On the other hand, in the WNBA, there are 2-4 per game, and it's usually not sloppy play. There are usually also 2-4 fouls per game on sloppy attempts to get a jump. I think it has to do with the different style of game in the WNBA from the NBA. I think that the difference between the women's game and the men's game runs clear down to 6th grade girls, where you see 376 jump balls per game as compared to 6th grade boys where there are only 5-10 per game.