Is Lucas Duda objectively streaky? Part 2

This is an expansion on Part 1, trying to determine how streaky a hitter Lucas Duda is. As I mentioned in Part 1, there really is no defined term for what 'streaky' means in baseball. Is it someone whose hot and cold streaks last for a longer duration? Is it someone who has hot and cold streaks with more frequency? Is it someone whose hot and cold streaks are more extremely hot or cold?

For lack of a better method, I'm going to use monthly wRC+ standard deviations, which is also what I used in Part 1. It should somewhat encapsulate all three aspects of streakiness mentioned above, albeit not perfectly. As mentioned by commenters in the last piece, one year's worth of data may have revealed if Duda was streaky in 2015, but it doesn't provide enough data to say whether or not you could attach the term 'streaky' to Duda's entire body of work to this point. (Note for clarification: Neither of these two points are relevant to a third question, which is whether Duda will be a streaky hitter in the future. I don't have data showing that past streakiness portends future streakiness, so I'm not equipped to answer that question.)

I looked at comparable players to Duda and ranked them based on their monthly fluctuations from the beginning of 2013 through May of 2016. I only looked at players that have been starting first basemen since the beginning of 2013 and remain so, with a minimum cutoff of Brandon Belt's plate appearances over that time period, as he only has 15 months' worth of sample size. For fun, I also added in James Loney, who surprisingly has 17 months' worth of data. Like in the last piece, a month only counts as a data point if a player accumulated at least 50 plate appearances.

The data actually shows that Duda is in the middle of the pack compared to his peers. He only ranks ninth out of the 15 first basemen in terms of streakiness, and the distance between him and the most consistent player, Anthony Rizzo, is smaller than the distance between him and the streakiest player, Edwin Encarnacion.

Even if we used Duda's 2015 standard deviation, which was 42.67, it would still place him well below what the top three have done over the last three seasons. Looking at the data for the other first basemen, in many cases, the players' reputations match with the data. Encarnacion and Davis both have reputations for being maddeningly streaky, while Goldschmidt is known for his remarkable consistency, and the data supports all of those assumptions. However, it might surprise many to see that Miguel Cabrera is also comfortably at the top of the list (very streaky), while Ryan Howard resides in the bottom half (not as streaky).

There are a couple potential reasons why Duda might seem extremely streaky compared to the rest of the Mets' lineup throughout the years.

1. The first possibility is that Duda does hit many of his home runs in bunches, which would make it seem like Duda is only producing when he's mashing the ball into the upper deck. However, Duda is remarkably consistent in drawing free passes, which sets a high floor on his level of offensive production. In fact, in 2015, he never walked less than 8% of the time in any month. He isn't one of those hitters whose plate approach completely breaks down when he's in a slump.
   
   
2. Power hitters may naturally have a higher baseline for average standard deviation. In other words, power hitters may innately be streakier. This is a somewhat unfounded claim that would need to be tested with more data, but it makes intuitive sense, and the data between this and Part 1 indicate it as a possibility. Intuitively, a home run constitutes a much larger percentage of offensive production and wRC+ than a single does. For example, when Lucas Duda gets hot, he hits a lot of homers; when Ruben Tejada goes on a hot streak, he hits many singles. In recent years, until the acquisition of Yoenis Cespedes, there have been many instances where Duda was the main, and sometimes only, source of power in the Mets' lineup, leading to a greater disparity in the minds of many fans between Duda and the more contact-oriented hitters.

Either way, through this one measurement, the data suggests that Duda may not actually be streakier than the average player of his position and offensive profile.