By the Numbers: The streakiest hitters of 2015

Consistent hitters make our jobs as Fantasy owners easy. What you see from them in a given week is typically what you'll get from them going forward. It follows, then, that streaky players make the management of our Fantasy rosters a difficult and frustrating task.

I recently identified this season's most consistent hitters, but now I'm turning my attention to the streakiest hitters of 2015. These are the players who made it the most difficult to pin down an expected level of production from week to week. Whereas the consistent types are ones who you might give more preference towards in Head-to-Head leagues, where one slumping player could sink your whole week, and 50-50 daily games, streaky players have more appeal in Rotisserie leagues and daily tournament games.

If we define streaky players as those who maintain a reasonable level of performance over the course of a season but frequently dip below replacement level at various stretches, the players in the table below would qualify as this year's streakiest hitters. To make the list, a hitter had to maintain an average of at least 0.60 Fantasy points per plate appearance (FPTS/PA) through the end of Fantasy Week 25. They also had to make plate appearances in at least 13 scoring periods (Weeks 15 and 16 were combined into a single scoring period) and compile a total of 400 plate appearances.

The players are ranked by the number of weeks in which they failed to average 0.40 FPTS/PA. To put this in perspective, Michael Bourn, J.J. Hardy and Domonic Brown are all hitters who have averaged 0.40 FPTS/PA this season. This is considerably worse than replacement level in most formats, so when a hitter didn't meet this threshold, he had a truly poor week. The table also includes the number of "quality weeks," or weeks in which a hitter exceeded 0.60 FPTS/PA, which we could also call the Longoria Line.

Quality Hitters with Frequent Poor Weeks

According to this ranking, Jung Ho Kang, Ryan Howard and Kevin Kiermaier have been this season's streakiest hitters, as each failed to reach 0.40 FPTS/PA in nine different weeks. Of the three, Kang would appear to be the streakiest, as he registered a quality week 14 times, as compared to 12 times for Howard and nine times for Kiermaier.

Hitters with the Most Poor Weeks (fewer than 0.40 FPTS/PA)

Note: Eight other players tied with seven weeks with fewer than 0.40 FPTS/PA.

This assessment probably isn't fair to Kang, as he settled into a much steadier pattern of production after being all over the map in his first three months as a major leaguer. Kang's more consistent results coincided with him getting more regular playing time, so his apparent streakiness may just be a result of how he was used. Though it is fair to label Kiermaier as streaky, it's not a relevant distinction for many Fantasy owners. By crossing the Longoria Line just nine times, Kiermaier hasn't provided sufficient upside to create a start/sit dilemma for owners in Head-to-Head leagues.

With the possible exception of Kang, it's not a stretch to label any of these hitters as streaky, but this ranking is not the best indication of which hitters had the biggest week-to-week swings in performance. For example, Todd Frazier had six different weeks in which he averaged at least 1.00 FPTS/PA but also five weeks with an average of 0.30 or lower. Gregory Polanco had just one less quality week and one less poor week than Frazier, but he exceeded 1.00 FPTS/PA only once and failed to exceed 0.30 FPTS/PA a mere three times. By looking at the frequency of quality and poor weeks, we don't see the full extent to which Frazier was streakier than Polanco.

Fantasy's Least Consistent Hitters

If we rank players by their week-to-week standard deviation in FPTS/PA, we get a better sense of how streaky they have been. By this measure, the runaway leader is Rougned Odor. Like Kang, he was a more productive hitter over the latter part of the season. Odor was a regular during both stretches, and the "good" and "bad" parts of the season were separated by a demotion to Triple-A. However, Odor was actually less consistent after he returned from his minor league demotion, with a standard deviation of 0.73, three weeks above 1.00 FPTS/PA, one week above 3.00 FTPS/PA and two weeks below 0.20 FPTS/PA.

Greatest Week-t0-Week Inconsistency, Nos. 1-10 (min. 400 plate appearances, 12 quality weeks)

A second Ranger has distanced himself from the pack. As a Rule 5 pick, Delino DeShields spent the whole season in the majors, though he did miss three weeks with a hamstring injury. Overall, he performed better in the first half, but he has experienced extreme highs and lows at various points throughout the season. Howard and Frazier deserve special mention here as well, as both are in this top 10 list as well as members of the Most Frequent Poor Weeks Club. It's not breaking news to Fantasy owners that their production is uneven, but now you have the numbers to back up your suspicions. The bigger surprise is that Howard (.720 OPS) had enough highs to merit inclusion on this list, as he did have multiple stretches of hefty production. The most notable of these was a five-week period from late April to late May in which Howard posted a 1.011 OPS and weekly FPTS/PA ratios in the 0.54-to-1.29 range.

Knowing the extreme nature of the streakiness displayed by Odor, DeShields and Frazier, as well as by Justin Turner and Justin Bour, you might be more reluctant to draft them next year in Head-to-Head formats. The same is probably not true for Nolan Arenado, Bryce Harper, Edwin Encarnacion and Josh Donaldson, nor should it be. All averaged at least 0.80 FPTS/PA and only Arenado and Encarnacion had weeks with fewer than 0.30 FPTS/PA (two weeks apiece).

Other Inconsistent Hitters of Note

As we move on to the next 10 players in the standard deviation rankings, we see that Russell Martin just missed out on the top 10. He was also among the leaders in most poor weeks, so that puts him in a similar class with Howard and Frazier. To look at Martin's month-to-month production, he actually seemed to be very steady this season, but within each month there were extreme highs and lows. Chris Davis, Carlos Gonzalez and Nelson Cruz built on their reputations for inconsistency, but none were quite as streaky as Ryan Braun. The Brewers' outfielder played better overall in the second half than in the first half, but he was even less consistent after the break.

Greatest Week-t0-Week Inconsistency, Nos. 11-20 (min. 400 plate appearances, 12 quality weeks)

Lorenzo Cain and Stephen Vogt took steps forward this season, but do owners worried about their ability to maintain their gains going into 2016 have something else to worry about? That's not the case for Cain, whose fluctuations were merely from good to great. Take away his dismal Week 23, during which he produced three singles, a walk, a hit by pitch and a steal in 24 plate appearances, and in his worst week, he still averaged 0.42 FPTS/PA. The picture for Vogt is less clear, as he was erratic after the first two months. He was also dealing with a variety of injuries for much of the season, but it's hard to say if those impacted his consistency and overall productivity, and if he can stay healthier next year.

As players like Harper, Donaldson and Cain demonstrate, streakiness isn't a bad thing in and of itself. Still, it raises the question of whether we are more likely to see their ceilings or floors next season, and that could impact whether, for example, you would take Harper with the first pick over Mike Trout (0.82 FPTS/PA, 0.32 ST DEV) or Paul Goldschmidt (0.87 FPTS/PA, 0.23 ST DEV). It's a safer bet to draft Harper, who is about to turn 23, based on his upside, than to make the same move for Donaldson or Cain, who will be 30 next season.

For streaky players with lower ceilings, like Turner and Martin, the risk to invest in them on Draft Day is considerably greater. The biggest dilemmas are with players like Frazier, Davis and Gonzalez, who at times looked like elites, but also endured too many weeks of mediocrity -- or worse. I will likely discount each of these hitters in drafts next year, with the deepest discounts coming in Head-to-Head leagues.