Luck, Skill and Sample Size in Playoff Shooting Percentage

In a discussion on a message board about my previous article on luck and skill in shooting percentage, someone asked about the numbers for the playoffs. The average series runs a little under 6 games. That makes the entire playoffs pretty close to a quarter of a season for the teams that make the Cup finals. Here are the numbers for how often the team that shoots at a higher percentage (about 7th best in the league) outshoots the team that is bad at shooting (~7th worst in the league):

Time period	Number of Shots	A scores more	B scores more	Goals scored equal	A > B Significant	B > A significant
Four Games	96	51%	38.1%	10.9%	7.4%	3.9%
Five Games	120	51.9%	38.7%	9.4%	7.6%	3.8%
Six Games	144	54.1%	37.5%	8.4%	7.8%	3.4%
Seven Games	168	55.4%	36.6%	8%	7.9%	3.1%
Second Round	274	57.4%	36.6%	6%	9%	3.1%
Conference Finals	411	60.5%	34.6%	4.9%	9.4%	2.7%
Stanley Cup Finals	548	62.9%	33.1%	4%	10.7%	1.9%

Something worth noting is that on average this gap in shooting from good to bad is worth a little less than a goal (0.88 goals) per series. Despite that, the team with less shooting talent still has between a 35% and 40% chance to get more goals at even strength in a series if they get the same number of shots, and another 8-10% shot at breaking even. The bounces don't always even out. That leaves a lot of room for luck, creating more shots and special teams.