Is Gloucester vs Exeter the best game in the Gallagher Premiership?

Ever since Exeter Chiefs beat Gloucester in their first ever premiership game back in 2010 the games between the two have often been closely fought. Maybe its my inbuilt bias as a Chiefs fan originally from Gloucester but I've long had a hunch that these games are one of the best fixtures in the calendar. So this weeks question is:

Is Exeter Chiefs vs Gloucester (and Gloucester vs Exeter Chiefs) the best game in English Premiership rugby? 

Since Exeter's promotion in 2010 they've met in 17 games;

Exeter have 9 wins, Gloucester 7 and there has been one draw. Just looking down the results below shows there have been some great contests down the years and there is rarely more than a score in it.
Chiefs have 4 wins over Gloucester at Gloucester compared to 3 defeats and a draw, and at Kingsholm its even closer with 4 home wins and 4 away wins.
Its also noticeable that neither side have ever 'doubled' each  other although Chiefs can do this if they win on Friday night. 

Date	Home	Score	Away
04/09/2010	Exeter Chiefs	22-10	Gloucester Rugby
08/01/2011	Gloucester Rugby	37-23	Exeter Chiefs
05/11/2011	Exeter Chiefs	19-24	Gloucester Rugby
24/03/2012	Gloucester Rugby	27-28	Exeter Chiefs
22/12/2012	Gloucester Rugby	18-16	Exeter Chiefs
04/05/2013	Exeter Chiefs	40-39	Gloucester Rugby
06/10/2013	Gloucester Rugby	12-29	Exeter Chiefs
29/03/2014	Exeter Chiefs	13-14	Gloucester Rugby
19/09/2014	Gloucester Rugby	22-25	Exeter Chiefs
03/01/2015	Exeter Chiefs	25-26	Gloucester Rugby
09/01/2016	Exeter Chiefs	19-10	Gloucester Rugby
15/04/2016	Gloucester Rugby	16-9	Exeter Chiefs
08/10/2016	Exeter Chiefs	27-27	Gloucester Rugby
06/05/2017	Gloucester Rugby	20-34	Exeter Chiefs
01/09/2017	Gloucester Rugby	28-21	Exeter Chiefs
08/04/2018	Exeter Chiefs	46-10	Gloucester Rugby
24/11/2018	Exeter Chiefs	23-6	Gloucester Rugby

But how does this compare of to the other fixtures? And how can we meaningfully compare them?

How do we score the best match?

I've decided to stick to looking at factors that give the most entertainment so we'll look at how the various fixtures in the Premiership stack up. 

Firstly its important to note 2 things:

• I've only compared fixtures since Exeter's ascent to the premiership in 2010 and I've excluded this seasons fixtures 
• And only those match ups that have had more than 10 matches in that time (I'm only counting Premiership leagues matches and playoff games, cup games have been excluded)

Points per game

So which fixtures have the most points scored?
The highest scoring fixture on average is Sale-Wasps with 52.3 points per game followed by Exeter-Worcester on 50.8 points. Gloucester-Exeter is down in 18th place with a healthy 46 points per game.

Closeness of matches

The total number of points is all well and good but it doesn't make for great entertainment if they are all scored by one side. So we also need to consider how close matches have been.

Average Winning Margin

This is one very simple way of comparing the closeness of fixtures, a simple average of the winning margin of matches between pairings of clubs.
The fixture with the lowest average points score is Newcastle and Sale, Exeter-Gloucester is the fifth best with a average of 8.1 points per game. The game with the most points per game, Sale-Wasps is 15th with and average of 9.1 points per game.

Close Games (within a single score)

Just relying on the average margin per game has its limitations of course and could be skewed by one or two one sided games. So I've also looked at the number of games which finish with less than 3 points, i.e. one successful kick could have changed the outcome. Newcastle-Sale finishes within 3 points in a massive 42.86% of games, followed by Newcastle-Worcester is next (40%) and our game, Exeter-Gloucester is third on 37.50%

Verdict

Looking at these three factors together and giving a simple ranking score for each one we can give an overall ranking for each of the fixture pairings considered and say which fixture performs best.
By ranking 18th for points per game, 5th for average margin and 3rd for the percentage of games which finish with a margin of < 3 points, Exeter-Gloucester scores 26 points and tops the table.
Which is the lowest score making it by this rather crude methodology the best fixture in Premiership rugby.
Mind you it does look like Gloucester are the best value side to watch with 5 fixtures in the top ten, Wasps appear 4 times and Quins three times. Conversely Saracens & Bath are conspicuous by their absence, and Exeter only appear once.

Fixture Pairing	Points per game	Average margin	% of matches with a less than 3 point margin	Ranking Points
Exeter Chiefs-Gloucester Rugby	46.0	8.1	37.50%	26
Gloucester Rugby-Wasps	49.5	9.5	31.25%	30
Sale Sharks-Wasps	52.3	9.3	18.75%	35
Leicester Tigers-Wasps	44.8	8.1	23.53%	46
Harlequins-Worcester Warriors	47.2	10.3	25.00%	48
Gloucester Rugby-Worcester Warriors	43.9	8.4	33.33%	50
Gloucester Rugby-Northampton Saints	44.6	9.2	31.25%	51
Harlequins-Wasps	47.0	11.1	31.25%	51
Harlequins-Sale Sharks	45.5	9.3	18.75%	53
Gloucester Rugby-Newcastle Falcons	44.7	9.6	28.57%	58

Speaking as someone who watches much of their rugby at Sandy Park, the data certainly bears out why I'm drawn to this fixture when thinking about the closest games. The head to head record and the margin of victory stats show these games are generally close and we are still waiting (at the time of writing) for the first double in a season for either of these two sides against the other.