All you know about basketball is wrong

Daryl Morey's best offensive play: just letting the players do their thing. Bill Baptist/NBAE/Getty Images

The Sloan Sports Analytics Conference (SSAC) is an annual pilgrimage for the most brilliant minds in professional sports. SSAC is challenging: The conference forces us to look at the sports we think we understand through new perspectives. And so, a few things you thought you knew:

  • Why you're wrong about play-calling: According to Houston Rockets general manager Daryl Morey, the most successful play Jeff Van Gundy ran while he was in Houston was simply setting a random screen and letting the players run the offense by themselves. The set plays were actually less efficient. Former NBA coach George Karl also added that one of the most valuable and underrated plays at the end of a game was simply gaining an offensive rebound.

  • Why you're wrong about emotion: For years, reams of data have said that your favorite announcer's favorite buzzword -- "momentum" -- has very little impact on real action. But Kevin Kelley, the high-scoring, never-punting coach of Arkansas' Pulaski Academy, says that his data suggests that drives after turnovers are almost twice as likely to produce points. If, as Kelley's numbers suggest, a hyped-up team is more likely to score, it may be time to give momentum a more thorough look.

  • Why you're wrong about the teams that make the most mistakes: More successful teams and coaches have more leeway for experimentation, and that often winds up creating more errors. Less successful teams play it safer and try not to rock the boat; they can't afford to risk as many errors.

  • Why you're wrong about blown calls: According the NBA's Mike Banton, the league will migrate to a system of centralized video replay next season. Decisions will still be handled by the officiating crew in the arena, but the NBA hopes that off-court replay will help speed up calls.

  • Why you're wrong about rebounding: While we tend to think of rebounding as a single event, it can actually be broken down into several smaller events: a field-goal attempt, a missed field goal, distance from the hoop relative to the other guys on the floor, and grabbing the ball. That's why you often see teams rebound better with certain guys on the floor when the guys themselves don't tally high numbers of rebounds. Take Nene, for example. His individual rebounding numbers don't turn heads, but when he's on the floor, his team tends to rebounds better because boxing out and not being in the high-value location (where the ball will land) allows his teammates to swing in and get the ball.

  • Why you're wrong about LeBron James: According to Kirk Goldsberry's EPV metric, Jose Calderon is one of the league's best at guiding his team to the most optimal outcome in any given NBA possession in which he's involved. Other members of the top 5: LeBron James, Dirk Nowitzki, Channing Frye, Chandler Parsons.

  • Why you're wrong about trades: The savviest GMs don't always stop negotiating trades after a "yes." When Houston acquired Kevin Martin from the Kings, the original deal was worked out as a trade for Tracy McGrady. The deal was later expanded to include the New York Knicks. The lesson: Deals can always be improved.

  • Why you're wrong about free agency: Carving out space on your payroll and roster for a free agent is key to acquiring someone even before they set foot into their agent's or your team's GM's office. Negotiations with players to secure potential deals often comes first. Afterward, the space-carving in-between steps occur. Then you can bring your free agent aboard. That's what Bob Myers did in negotiations with Andre Iguodala.

Watch this space throughout the weekend to learn about everything else you thought you knew.