Daily/Weekly Projections: New Pitcher Factor - MLB Parks

ken_admin  5/1/2013 1:28 PM

We've added park factors to the pitcher projections for daily and weekly.  Next will be Opposing Hitters factor for pitchers.

liam4  5/1/2013 8:30 PM

yeehaw!  thank you.

one thing i had been thinking about -- will there be a way to have revised pitcher projections (for park factors) affect the hitter projections (adjusted for opposing pitcher)?  i think there is some inaccuracy when a Colorado pitcher is away, for example; his high ratios result in enhanced hitter projections, but they are skewed by the games at Coors.  Same with a SD pitcher away, with low ratios.

Or does it already do this?  I figure you don't want to double count park factors, so could you use home/away splits -- for a Colorado pitcher away, his numbers are adjusted to what he typically does away from Coors, vs. specifically to the ballpark in question.

ken_admin  5/2/2013 10:33 AM

Yes, you are correct.  Currently, the hitter projections are based on the default values for the opposing pitcher rather than the park-adjusted pitcher.  It sounds like we should remove the pitcher's home adjustment that's built into their default projection, but we'll give that more thought to make sure it's not double-adjusting as you mentioned.  Ideally, we would store projections as park-neutral and adjust based on schedule, but that's unlikely for this season. Thanks for pointing it out.

Rapierman   5/5/2013 12:28 PM

Another thing to think about when determining park factors is the field construction:  Grass vs. Astroturf (does it exist anymore?) vs. Prescription Athletic Turf.  The reason for this is that the ball, when hit along the ground, bounces differently each time.  Astroturf (and I'll go ahead and assume that this is the same for PAT) has true bounce physics, whereas in natural grass the ground is uneven, making for the occasional "strange hop".  Addtionally, the friction of AT/PAT is different as opposed to natural grass/ground.