I've been wondering for a while now how well a team's march through the end of the regular season predicts their playoff results. I think the conventional wisdom is that it's not good to go into the post-season losing a number of your final games, as that either carries over or simply foreshadows the ultimate playoff demise. With the Penguins stuck right now in an inconsistent stretch of games that sees them win games 5-1 and lose them 4-0, some have predicted this means another first round exit in the playoffs. Here is a Reddit thread suggesting as much.
So with this mind, I decided to look at a team's record over its final 12 regular season games and compare that to its playoff record for that year. Picking the number of regular season games to look at is inevitably arbitrary. But 12 was a nice number since it was 1/4 of the 2013 shortended season. I also think it's a good number since it's long enough to capture a prolonged trend (rather than just a bad game) and short enough so that we don't have multiple long-term trends wrapped up in one set.
Here is a chart with the 2012-2013 records for the teams that made the playoffs (please click all images to enlarge):
It's tough to see how related the numbers are by just looking at them. So I had excel generate a scatterplot with a trendline to show any correlation. As a rule of thumb, the greater the R squared value (from 0 to 1), the stronger the positive correlation. The scatterplot is below:
Both clear and startling in my eyes. There is literally no correlation between a team's record in its final 12 regular season games and its record in the playoffs. Because of this, I decided to do the same thing for the 2011-2012 season since that was a full season, and this could be a weird byproduct of the shortened 2013 season. Below is the chart for the 2011-2012 season:
And here is the scatterplot:
Same result. Literally no correlation.
I should be clear - I don't think this means teams should be content to play crappy hockey as the regular season winds down, thinking they can just reset everything in the playoffs. No one wants to lose and it's probably unlikely teams can just turn the switch on when they want. But there really is no relationship between how teams finish the regular season and how they perform in the playoffs. If the Penguins struggle down the stretch, that doesn't mean they're toast. Likewise, if they crush the end of their regular season schedule, that's not a guarantee they're going to the Cup final.
Suffice it to say, be skeptical of anyone claiming teams need to play well at the end of the regular season if they hope to go far in the playoffs. There really is no basis for that.