Playoff success 101b

Part III: PP or not PP?

It's been a while, but since I've now unexpectedly re-discovered that the NHL season does in fact not end this Sunday, what better time to carry out another essentially meaningless and unproductive analysis of playoff trends?

(My previous investigations can be found HERE and HERE – not essential reading, but might make some of the following slightly more understandable, since I can't be bothered with another full explanation.)

Today's hypothesis is another of the well-worn lines spouted by your favourite hockey analysts (and Brian Engblom) at this time of year: You can't win in the playoffs without a good powerplay

As it's almost two sides of the same coin, I thought I'd also look at whether a strong penalty killing unit was any indicator of success.

The Werk Wot I Did

• Similar to before, order all NHL teams by both PP and PK rank in each of the last 10 regular seasons (back to 1997/98 – 2004/05 was excluded as it wasn't very interesting to look at)
• Look at how these numbers translated to playoff failure or success
• Construct the usual tables to try and illustrate whether there are any strong trends
  

Obvious drawbacks

• Much as before...10 years isn't a huge sample size and regular season performance doesn't automatically translate to post-season play
• There is also likely to be a certain amount of correlation between this analysis and the previous ones (which looked at goals for and against, if you really haven't clicked on the links above) – high-scoring teams are more likely to have a strong PP (or teams with a strong PP are more likely to be high-scoring), similar with defense and the PK
  

Key



Ranking charts
The charts below show the overall league PP and PK ranking and the stage of the playoffs each team made. At the bottom of each is the average rank of the teams reaching each playoff round in each year, with the overall 10-year average in the far right column. (Note that the average for each round includes all teams that made that round, not just those that got knocked out.)




Observations

• The 10-year average rankings are pretty similar when comparing PP and PK – a slightly higher PK ranking for Cup Finalists compared to PP (9.3 vs 11.2) being the main difference
• There doesn't appear to be much of a correlation between PP/PK success and playoff progress (possibly only a weak relationship when looking at PK alone) – while there are clusters of highly-ranked teams in each case that made the Conference Finals or better, there are plenty of examples of mid-ranked teams doing well
• The correlation between GF/GA ranking and just making the playoffs seems to be a bit stronger than for PP/PK ranking (i.e. the 10-year average rankings are a bit lower) – the playoff teams (in colour) in these charts are less concentrated towards the top
• Notable anomalies: The 2006/07 Canadiens and 2005/06 Wild being top-ranked in PP and PK respectively, but missing the playoffs entirely; the offensive juggernaut that was the 2002/03 Devils managing to win the Cup despite having the worst regular season PP in the league
  

This season?
The chart below shows the current (through games played on 9 April) PP and PK rankings – teams that have clinched playoff spots in orange, the four teams still in the race in the West in purple:



Observations:

• As noted on the NHL.com front page today, PP success rates are up this year (as a Ranger fan, I have seen absolutely no evidence of this phenomenon though) – in the last 10 seasons, there have tended to be three or four teams with a PP% above 20%, but there are eight at the moment
• Average rankings for playoff teams are not too dissimilar from those shown above (a little on the low side if anything, but higher than last year)
• It's not unprecedented for the Blue Jackets and Rangers to have overcome lousy PP numbers to make the playoffs, but still difficult to expect a deep run without some improvement in that area
• On the PK side, the Kings are much improved (bottom-ranked in each of the last three years), the Wings have slumped significantly (cause for concern?) and the Leafs' PK% is the worst in the last 11 seasons by some distance