It works out as a sort of trade.

The Lakers sign Ron Artest as a free agent, for three seasons and about $18 million, away from Houston.

The Rockets sign Trevor Ariza as a free agent, for five seasons and about $30 million, away from the Lakers.

And I like what the Lakers have done, because Artest is an improvement on Ariza. At least for now. And “now” is what matters most to these Lakers and Kobe Bryant.

Ariza may be a better player, long-term. But the Lakers are thinking 2-3 seasons down the line, while Bryant is ages 31, 32, 33. After that, when Kobe almost inevitably will be in palpable decline, having a sagging Artest instead of a peaking Ariza … probably won’t be a matter of much regret. Because the Lakers are far less likely to be serious championship contenders anymore. And if Ariza, by then, has turned into a star for the Rockets … well, good for them.

I like Ariza. I wouldn’t have minded if the Lakers kept him. Excellent defender. Made the Lakers more athletic. Made a lot of threes in the playoffs. And he’s only 24.

But Artest is just as good. Actually, a little better. And plays the same “3” position.

Artest is a little goofy. OK, sometimes he seems not quite sane. Like when he was one of the Pacers who went into the stands after fans at Detroit in 2004 (and was suspended for the rest of the season, 73 games). Or when he decides to wear a mohawk. And shave a Rockets logo into the side of his head.

But this appears to be an Artest who is ready to become a cog — yes, a key one — in the Lakers organization. He is ready to be a sidekick. A complimentary player. He turns 30 in November, and he feels time closing in on him.

He is a better scorer than Ariza. A little stiffer. Not as athletic. But he is used to putting up points, if needed. he has averaged at least 17 points per game for seven consecutive seasons.; Ariza’s regular-season high is 8.9 ppg.

Most importantly, Artest is a better three-point shooter. Artest is a 34.2 percent shooter from three-point range in his regular-season career. Ariza is at 29.9 percent. Yes, but Ariza is getting better at it, you might say. And you’d be right. But Artest is becoming a better perimeter shooter, as well — going from 30.8 percent in 2005-06 to 35.8 percent the next season to 38.0 the next and 39.9 in 2008-09. That’s a significant and steady rise.

Also, Artest has shot some threes with a defender in the general area. Ariza almost always shot uncontested threes, especially with the Lakers. And didn’t make as many.

I believe the Lakers organization is strong enough to keep Artest from getting too wacky. I’m thinking he grasps this and will tone down the “look at me” weirdnesses. “Dude, this is Kobe’s team, and Kobe doesn’t go in for freakish teammates.” All the same, Artest may make things a little more fun. One more guy whose opinions may brighten otherwise dark days in the dreary parts of the regular season. Ariza may be a lot of things, but he never gave off a sense he was going to be a quote machine at some point in the future.

I also like that Artest essentially campaigned for this job, showing up at Lakers games in L.A. after he and the Rockets were eliminated in that seven-game slugfest. That he suggested he was available. That he already has met with Jerry Buss and Phil Jackson. I like that he wants to be with the Lakers. It’s like it was with Karl Malone and Gary Payton, back in the 2003-04 season — except Artest isn’t over the hill, like those guys were.

I believe Artest, the player, will be their stopper-type defender of opposition forwards, and I am confident he can score about 40 percent of those wide-open threes he is going to get while playing on the same team with Kobe Bryant, Pau Gasol and Andrew Bynum.

I thought the Lakers would fall off, if they let Ariza get away. But by signing Artest — who clearly is in “I want to win a ring” mode — the Lakers have gotten better. For this coming season. And the next.

After that? Well, we’ll see. But I think looking more than 2-3 years down the road is hardly worth the trouble.

These Lakers can win again next season. Perhaps more easily, now that they have added Artest.