1983-84 and PDO

Rather than gradually work my way back in time, I thought it best to just jump straight back to the first possible year to calculate PDO: 1983-84.

It was a different time.  The season began with Bonnie Tyler’s “Total Eclipse of the Heart” at the top of the charts, soon to be knocked off by “Islands in the Stream”.  Martin Luther King Day was officially declared a national holiday.  Able Archer 83 unknowingly brought the Soviets and Americans to the brink of WWIII.  And the NHL finally began tracking shots against, allowing for retroactive PDO.

In the write-up I did on PDO in the first place, I noted that:

  • An all-situations PDO higher than 100.9% very strongly correlates to a playoff appearance
  • A PDO below 99.2% very strongly correlates to missing the playoffs
  • PDO has little predictive value in the playoffs, although I pointed out that further research would be needed.

The following table shows each team’s all situation PDO in 1983-84.  The key numbers are on the right: “PDO” is the original number I had without taking the empty net goals into account, and “AdjPDO” is the big number that has everything properly balanced and comes out to a leaguewide total of 100.0000000000.  SV% is the total number of goals against from number of shots against; TmSV% includes the empty net shots (which had to be adjusted for).  In this table, AdjPDO is simply S% plus TmSV%.

Team GF S GA SA EN S% SV% TmSV% PDO AdjPDO
Edmonton 446 2613 314 2638 4 17.069 0.881 0.881 105.166 105.184
NY Islanders 357 2423 269 2669 1 14.734 0.899 0.899 104.655 104.659
Quebec 360 2286 278 2249 2 15.748 0.876 0.876 103.387 103.398
Boston 336 2398 261 2091 3 14.012 0.875 0.875 101.530 101.547
Buffalo 315 2388 257 2146 2 13.191 0.880 0.880 101.215 101.226
Washington 308 2534 226 1961 4 12.155 0.885 0.885 100.630 100.653
Minnesota 345 2536 344 2605 5 13.604 0.868 0.868 100.399 100.424
NY Rangers 314 2552 304 2505 9 12.304 0.879 0.879 100.168 100.212
Calgary 311 2565 314 2625 3 12.125 0.880 0.881 100.163 100.177
Toronto 303 2344 387 2826 6 12.927 0.863 0.863 99.232 99.261
Philadelphia 350 2945 290 2287 5 11.885 0.873 0.873 99.204 99.232
Hartford 288 2402 320 2482 5 11.990 0.871 0.871 99.097 99.123
Chicago 277 2459 311 2519 7 11.265 0.877 0.877 98.919 98.953
St. Louis 293 2427 316 2392 8 12.072 0.868 0.868 98.862 98.906
Winnipeg 340 2584 374 2619 2 13.158 0.857 0.857 98.878 98.889
Detroit 298 2326 323 2300 14 12.812 0.860 0.860 98.768 98.853
Vancouver 306 2494 328 2338 12 12.269 0.860 0.860 98.240 98.312
Montreal 286 2293 295 2051 4 12.473 0.856 0.856 98.090 98.118
Pittsburgh 254 2267 390 2896 12 11.204 0.865 0.866 97.737 97.793
Los Angeles 309 2467 376 2524 11 12.525 0.851 0.852 97.628 97.693
New Jersey 231 2101 350 2554 5 10.995 0.863 0.863 97.291 97.318

The first thing to note is that there are only six teams inside the 99.2%-to-100.9% range at all.  I believe this to be a symptom of a significantly unbalanced league, one which saw just five teams finish within 10% of .500.  There were also five 100-point teams, meaning that in a 21-team league there were as many teams that finished with 100+ points as finished anywhere between 72-88.

In the Campbell Conference, exactly three out of ten teams finished above .500: Calgary at 34-32-12, Minnesota at 39-31-10, and Edmonton at 57-18-5.  Both Minnesota and Calgary would have missed the playoffs if they had been in the Patrick Division, and either one would have been the #4 seed in the Adams.

However, we must still see if PDO had any predictive value at this time despite the divisional playoff system and the unbalanced league.

In the first round:

  • Montreal (lower) defeated Boston (higher)
  • Quebec (higher) defeated Buffalo (lower)
  • NY Islanders (higher) defeated NY Rangers (lower)
  • Washington (higher) defeated Philadelphia (lower)
  • Calgary (higher) defeated Vancouver (lower)
  • Edmonton (higher) defeated Winnipeg (lower)
  • St. Louis (higher) defeated Detroit (lower)
  • Minnesota (higher) defeated Chicago (lower)

That’s 7-1 in the first round for the higher PDO team.  And of these, despite the lack of overall competitive balance, only two series involved a massive disparity in team points that season: Edmonton finished 46 points ahead of Winnipeg and swept them, and Boston finished 29 points ahead of Montreal but were themselves swept.

In the second round:

  • NY Islanders (higher) defeated Washington (lower)
  • Montreal (lower) defeated Quebec (higher); this was the series that featured the infamous Good Friday Massacre
  • Edmonton (higher) defeated Calgary (lower)
  • Minnesota (higher) defeated St. Louis (lower)

That’s another 3-1 for the higher team.

And the rest of the way:

  • Edmonton (higher) defeated Minnesota (lower)
  • NY Islanders (higher) defeated Montreal (lower)
  • Edmonton (higher) defeated NY Islanders (lower)

All in all, that’s a shocking 13-2 overall record for the higher PDO team in each playoff series.