January 30, 2009

# A consistency index for batsmen

A stats analysis to measure the consistency of Test batsmen

One thing we admire in our cricketers is consistency. Full marks to the gritty player who scores 50 on a minefield, even though he gets out for 50 when well set on a featherbed. But do we admire so much his team-mate who gets a duck in the first instance, but makes amends by crashing an impressive 100 in the second? They have the same average - but do they provide the same value?

Consistency can measured by calculating the standard deviation, which, in simple terms, seeks to measure the average deviation that each score is from the overall mean. The lower the standard deviation, the lower the variation in the scores. We can obviously apply this to cricket scores, but a couple of issues need to be resolved: what to do with "not out" scores, and how can we use it to compare the consistency of players with different averages?

To resolve the first, I elected to add any uncompleted innings to the next innings, so that effectively, I was calculating the standard deviation of the runs made between dismissals. If the last innings was a "red ink", it was ignored.

To allow comparison of consistency between different players, I simply divided the calculated standard deviation by the batting average (ignoring the last innings if it was "not out").

I performed this exercise three times for Test cricketers; for those who scored at least 1000 runs, for those who scored at least 5000 runs, and for those who scored at least 10000 runs.

The first table lists the most consistent Test batsmen who have scored at least 1000 runs. Australia's Bruce Laird, who scored with such consistency without scoring a century in his brief late-70s career, heads the list, and is followed by the admirable Sutcliffe, whose consistency is astounding given the extent of his career. Alastair Cook and MS Dhoni are notable current players in this list.

 Batsman Team CI SD Average Matches Innings Not Out Runs Bruce Laird Australia 0.75 26.48 35.29 21 40 2 1341 Herbert Sutcliffe England 0.78 47.22 60.73 54 84 9 4555 Douglas Jardine England 0.79 37.08 46.70 22 33 6 1296 Ashley Giles England 0.80 16.81 20.90 54 81 13 1421 Alastair Cook England 0.81 34.24 42.09 36 66 2 2694 Maurice Tate England 0.82 20.96 25.49 39 52 5 1198 Rusi Surti India 0.83 23.72 28.70 26 48 4 1263 Jock Cameron South Africa 0.83 25.05 30.22 26 45 4 1239 George Gunn England 0.83 33.39 40.00 15 29 1 1120 Chandika Hathurusingha Sri Lanka 0.84 24.74 29.63 26 44 1 1274 Ian Redpath Australia 0.84 36.62 43.46 66 120 11 4737 Sid Barnes Australia 0.85 53.39 63.06 13 19 2 1072 Mark Richardson New Zealand 0.86 38.33 44.77 38 65 3 2776 Taufeeq Umar Pakistan 0.87 34.22 39.30 25 46 2 1729 Imran Farhat Pakistan 0.88 29.02 33.10 27 51 1 1655 Charles Kelleway Australia 0.88 32.83 37.42 26 42 4 1422 Dwayne Bravo West Indies 0.88 28.74 32.73 31 57 1 1833 Peter Richardson England 0.88 33.08 37.47 34 56 1 2061 Chetan Chauhan India 0.89 28.07 31.58 40 68 2 2084 Colin Bland South Africa 0.89 43.67 49.09 21 39 5 1669 Trevor Goddard South Africa 0.89 30.67 34.47 41 78 5 2516 Deryck Murray West Indies 0.89 20.40 22.91 62 96 9 1993 Mahendra Singh Dhoni India 0.89 32.20 36.14 35 56 6 1807 David Sheppard England 0.89 33.70 37.81 22 33 2 1172 Alan Davidson Australia 0.89 21.97 24.59 44 61 7 1328

At the other end, we also have some current players in the least consistent category, notably Sinclair, Taibu, and until recently, Atapattu, who mixed a dreadful sequence of low scores early in his career with some heavy scoring later on:

 Batsman Team CI SD Average Matches Innings Not out Runs Matthew Sinclair New Zealand 1.62 52.70 32.55 32 54 5 1595 Vinoo Mankad India 1.51 47.57 31.48 44 72 5 2109 Jacques Rudolph South Africa 1.49 53.81 36.21 35 63 7 2028 Guy Whittal Zimbabwe 1.48 43.65 29.43 46 82 7 2207 Tatenda Taibu Zimbabwe 1.45 42.94 29.60 24 46 3 1273 Wasim Akram Pakistan 1.44 32.57 22.63 104 147 19 2898 Mohammad Ashraful Bangladesh 1.43 34.10 23.88 48 93 4 2125 Javagal Srinath India 1.43 20.31 14.21 67 92 21 1009 Wasim Jaffer India 1.42 48.30 34.11 31 58 1 1944 Vic Pollard New Zealand 1.41 34.35 24.35 32 59 7 1266 Dilip Sardesai India 1.40 55.10 39.24 30 55 4 2001 Sidath Wettimuny Sri Lanka 1.39 40.31 29.07 23 43 1 1221 Marvan Atapattu Sri Lanka 1.39 54.40 39.02 90 156 15 5502 Matthew Elliot Australia 1.38 46.20 33.49 21 36 1 1172 Madan Lal India 1.38 31.27 22.65 39 62 16 1042 Ridley Jacobs West Indies 1.37 38.70 28.32 65 112 21 2577 Tim Robinson England 1.36 49.34 36.39 29 49 5 1601 Bill Ponsford Australia 1.35 65.00 48.23 29 48 4 2122 John Bracewell New Zealand 1.35 27.56 20.43 41 60 11 1001 Jimmy Adams West Indies 1.35 55.72 41.26 54 90 17 3012

Now for the serious Test batsmen:

 Batsman Team CI SD Average Matches Innings Not Out Runs Jack Hobbs England 0.92 52.33 56.95 61 102 7 5410 Don Bradman Australia 0.94 93.49 99.94 52 80 10 6996 Arjuna Ranatunga Sri Lanka 0.94 33.48 35.50 93 155 12 5105 John Wright New Zealand 0.97 36.58 37.83 82 148 7 5334 Mark Waugh Australia 0.97 40.58 41.82 128 209 17 8029 Graham Thorpe England 0.98 43.25 44.23 100 179 28 6744 Rohan Kanhai West Indies 0.98 46.58 47.53 79 137 6 6227 Clive Lloyd West Indies 0.99 46.44 46.68 110 175 14 7515 Denis Compton England 1.00 49.9 50.06 78 131 15 5807 Sourav Ganguly India 1.00 42.22 42.18 113 188 17 7212 Bill Lawry Australia 1.03 48.43 47.15 67 123 12 5234 Ken Barrington England 1.03 59.9 58.28 82 131 15 6806 Matthew Hayden Australia 1.04 52.77 50.74 103 184 14 8625 Ricky Ponting Australia 1.05 59.47 56.88 128 215 26 10750 Michael Slater Australia 1.05 45.09 42.84 74 131 7 5312 Doug Walters Australia 1.06 50.86 48.10 74 125 14 5357 Marcus Trescothick England 1.06 46.34 43.80 76 143 10 5825 Sunil Gavaskar India 1.06 54.42 51.12 125 214 16 10122 David Gower England 1.07 47.29 44.25 117 204 18 8231 Vivian Richards West Indies 1.07 53.69 50.24 121 182 12 8540 Michael Atherton England 1.07 40.41 37.70 115 212 7 7728 Len Hutton England 1.07 60.86 56.67 79 138 15 6971

The higher Consistency Indices show that it is much harder to maintain consistency over a longer career. It is interesting to observe that the two most consistent batsmen are two "old-timers", Hobbs and Bradman - class will out! And who would have thought that the most consistent Australian after Bradman in this category was Mark Waugh!

At the other end of the scale for this category, we find Waugh's twin brother prominently placed:

 Player For CI SD Ave M I NO Runs Marvan Atapattu SL 1.39 54.40 39.02 90 156 15 5502 Zaheer Abbas Pak 1.32 59.29 44.80 78 124 11 5062 Kumar Sangakkara SL 1.31 71.23 54.38 78 129 9 6525 Virender Sehwag Ind 1.27 64.81 51.06 66 114 4 5617 Steve Waugh Aus 1.26 64.16 51.06 168 260 46 10927 Shivnarine Chanderpaul WI 1.25 62.37 49.72 114 196 31 8203 Brian Lara WI 1.24 65.33 52.89 131 232 6 11953 Herschelle Gibbs SA 1.24 51.85 41.95 90 154 7 6167 Ian Botham Eng 1.24 41.69 33.55 102 161 6 5200 Sanath Jayasuriya SL 1.23 49.15 40.07 110 188 14 6973 VVS Laxman Ind 1.22 54.24 44.46 102 169 24 6446 Aravinda de Silva SL 1.21 52.21 42.98 93 159 11 6361 Mark Taylor Aus 1.19 51.55 43.50 104 186 13 7525 Wally Hammond Eng 1.19 69.46 58.46 85 140 16 7249 Jacques Kallis SA 1.19 64.91 54.58 128 216 33 9988 Mahela Jayawardene SL 1.18 61.73 52.36 100 164 12 7959 Carl Hooper WI 1.18 43.09 36.47 102 173 15 5762 Sachin Tendulkar Ind 1.1 64.28 54.28 156 256 27 12429 Rahul Dravid Ind 1.17 61.07 52.28 131 227 26 10509 Stephen Fleming NZ 1.17 47.05 40.07 111 189 10 7172

The case of Chanderpaul is interesting. Ten years ago, he was heading towards being one of the most consistent batsmen ever, with a CI of 0.82. Over the last decade, while he has been one the Windies few shining lights, there has also been much greater variation in his scoring.

This group also contains a few batsmen who play more aggressively than most: Sehwag, Jayasuriya and Botham are notable here. One would expect, naturally, their consistency to suffer as a result of their aggression.

Finally, a table just for the mega-stars, those who have scored 10000 Test runs, plus Kallis, who will surely join them the next time he goes to bat:

 Player For CI SD Ave M I NO Runs Ricky Ponting Aus 1.05 59.47 56.88 128 215 26 10750 Sunil Gavaskar Ind 1.06 54.42 51.12 125 214 16 10122 Allan Border Aus 1.08 54.45 50.37 156 265 44 11174 Rahul Dravid Ind 1.17 61.07 52.28 131 227 26 10509 Sachin Tendulkar Ind 1.18 64.28 54.28 156 256 27 12429 Jacques Kallis SA 1.19 64.91 54.58 128 216 33 9988 Brian Lara WI 1.24 65.33 52.89 131 232 6 11953 Steve Waugh Aus 1.26 64.16 51.06 168 260 46 10927

I for one was surprised to find the Aussie captain heading this list, and Tendulkar so far down the table. And perhaps Gavaskar was a better player than he is perhaps given credit for.

I hope the browsers of this site find this a worthwhile exercise. I would value their comments.