Science Buddies: "Ask an Expert"

My son is going to be doing an experiment to study whether starting position of a basketball- chest level, chin level, or over the head- affects shooting percentage. He will be using 10 players, each making 20 free throw shots per starting position, videoing results, and analyzing the video frames to see which degree arc/trajectory results in best shooting percentage. In trying to control variables as much as possible, we are not clear how to ensure that each starting position is truly kept constant across each individual player. Starting positions will inevitably vary based on player's height. Is there some way to measure the starting place of the shot so it is the same regardless of each's player height? My son's hypothesis is that chin level (medium arc vs too high or low) will result in best shooting percentage. I feel like there is a good amount of data that can be derived from video analysis, we are just not sure we are designing the experiment properly.

Any guidance you can offer would be greatly appreciated, even if we have to adjust the experiment significantly to make results more reliable. Thanks!

Miriam

Hi,

Sounds like a well-thought-out experiment! In order to make starting place the same, I would suggest measuring the tallest player's height and using books, stools, or other props for the shorter players to stand on to make each player's height equal to that of the tallest person -- although if all the players are of similar height, one or two inches isn't going to make much of a difference. Also, when you take a video, I would suggest using slow motion so it's easier to obtain data. If you have any more questions, please don't hesitate to ask!

Elena