Power and Patience (Part I of a Study)

(Note: “Patience” here is really shorthand for “ability to get on base,” whether that’s via hits or walks. But it’s pithier and generally gets the point across as to what I’m trying to look at.)

In one of the Thursday chats on FanGraphs with Eno Sarris, I posed the following question, which he posted and the chatters answered collaboratively: Name the three players (minimum 3000 plate appearances) in the expansion era (since 1961) with a career on-base percentage above .400 and an isolated power number below .200. (Answers at the end of this post.)

In the entirety of baseball history, 36 players with 3000 plate appearances have achieved such numbers, and 24 since the beginning of the 20th century, but there are only three such players in the past 50 years. This is not particularly surprising; you won’t see many career lines such as Ty Cobb’s .366/.433/.512 anymore, or even Paul Waner’s .333/.404/.473.

But just how has the relationship between hitting for power and getting on base changed through the years?

Since we started at the individual level, let’s continue there. Let’s start with the last 20 years, from 1994-2013. Excluding pitchers, the league-wide on-base percentage was .338 and the league-wide ISO was .159. Over that time period, 761 players have had 1500+ plate appearances. How they break down on OBP and ISO lines:

Now, 1901-1920, during which time only 377 players had 1500+ plate appearances and the league averages were a .326 OBP and .082 ISO:

In either era, a substantial majority of players had either both an above average OBP and ISO, or both were below average. However, that majority is 59% in the last 20 years and was 68% in the deadball era. So one conclusion we can draw is that fewer players now sacrifice power to reach base or vice versa than they did in the olden days. (Whether they did so consciously or not.)

However, this breaks down if we go to extremes.*

From 1994-2013, 13 players had an OBP 10% above average and ISO 10% below average, while there were 15 players with an ISO 10% above average and OBP 10% below average. Overall, 3.7% of all players with 1500 PA are here.

From 1901-1920, 8 players had an OBP 10% above average and ISO 10% below average and 5 players had an ISO 10% above average and OBP 10% below average. Overall, 3.4% of the players with 1500 PA.

Players who get on base without power or hit for power without getting on base are basically as common now as they were in the dead ball era. But it’s also less common now for a player to sacrifice one or the other to any degree.

What about this power-patience relationship league-wide?

First, below are some league-wide stats over various time frames (excluding pitchers):

A lot of famous seasons like 1930, 1968, and 1987 are identifiable on the chart. (The lowest ratio of the expansion era actually occurred in 1976, not 1968, however.) Also, it wouldn’t greatly surprise me if Babe Ruth is single-handedly responsible for the sharp increase from 1918 to 1921. (He got on base a lot, of course, but his power was the thing.) Most importantly, however, it’s clear that over time the ability of Major League player to hit for power has gone up relative to their ability to get on base. This too is not surprising to those familiar with baseball history.

And so all of this really only gives us a limited idea of the relationship between reaching base and hitting for power over time. Over the next few weeks, we’ll go further into things, both on the individual level and league level. Working backwards, next week will focus on the data underlying the above line chart.

Answers to the initial question:

Joe Mauer (.405 OBP, .145 ISO)
Rickey Henderson (.401 OBP, .140 ISO)
Wade Boggs (.415 OBP, .115 ISO)

*It’s not a Rickroll, it’s a Joelroll, which is even better because it rhymes.