What is the Most Important Sitting Volleyball Skill in the Men’s Game? Using Match Data from the 2012 Men’s Sitting Volleyball Paralympics Games

INTRODUCTION I done a review of the research on the most important skill in volleyball, i.e. which statistics is associated with a successful outcome.  I have looked at the Olympics to see whether this still held true, using the men’s and women’s official statistics.  However, I have not seen any research into the most important skill in sitting volleyball.  With my experience as a Sitting Volleyball Statistician at the Paralympics, I wanted to know whether there is any differences.

WHAT DID I FOUND OUT?  (FOR THOSE WHO WANT A QUICK ANSWER)BUT… Again, this is not a definitive answer.  There are many sources of potential error.  No statistical testing was performed so it is not known whether any result is significant.  It is known that the majority of the statisticians were novices so not all ball touches were called out (I know myself I missed some calls) and even then it may not have been recorded properly into the system.  I have seen ball actions being changed or even deleted by the Omega operator to ensure the rally sequence is logical.  No inter-operator reliability testing was done (whether different statisticians will record the same performance in the same way).  Operational terminology was discussed and agreed upon prior to the tournament but it may have been useful to have some sort of manual and associated videos to make it clearly defined and referred to.

METHODOLOGY (FOR THOSE WHO WANT A LONG ANSWER)

I have compared a team’s tournament rank with their performance indicator rank.  There are two performance indicators for each 6 technical skill, except for setting where there is only one.  If their tournament rank matches their performance indicator rank then I have highlighted it green.  If it is one rank away then I have highlighted it orange.  If it two or more ranks away then I have highlighted it red.  Achieving a green highlight is stricter than the Olympics because every team individually ranked in the Paralympics.  For example, teams that lose in the Olympic Quarters Finals are ranked 5th to 8th and any performance indicator rank between 5th and 8th are highlighted green.  In the Paralympics, teams that lose in the quarter finals play each other for the 5th to 8th classification.  I have also grouped the teams’ tournament rank to those who reached the finals (1st to 2nd), teams that lost the semi-finals (3rd to 4th), teams that played the 5th/6th classification (5th to 6th), teams that played the 7th/8th classification (7th to 8th) and teams that did not progressed beyond the group stages (9th to 10th).  No statistical testing have been performed so no significant results are known.

ATTACK ANALYSIS The huge number of orange squares and few red squares mean there is a close association to a successful performance.

Tour. Rank	Team	Spikes	Faults	Shots	Total	H%	H% Rank	AER	AER Rank
1	Bosnia & H	269	130	385	784	17.73%	3	2.069	2
2	Iran	303	145	326	774	20.41%	1	2.090	1
3	Germany	347	176	440	963	17.76%	2	1.972	4
4	Russia	318	177	398	893	15.79%	6	1.797	6
5	Brazil	255	131	348	734	16.89%	5	1.947	5
6	Egypt	319	205	491	1015	11.23%	7	1.556	7
7	China	310	151	461	922	17.25%	4	2.053	3
8	GB	183	146	353	682	5.43%	8	1.253	8
9	Rwanda	105	150	236	491	-9.16%	10	0.700	10
10	Morocco	111	104	291	506	1.38%	9	1.067	9
Tour. Rank	Team	Spikes	Faults	Shots	Total	H%	H% Rank	AER	AER Rank
1st – 2nd		572	275	711	1558	19.06%	1	2.080	1
3rd – 4th		665	353	838	1856	16.81%	2	1.884	2
5th – 6th		574	336	839	1749	13.61%	3	1.708	3
7th – 8th		493	297	814	1604	12.22%	4	1.660	4
9th – 10th		216	254	527	997	-3.81%	5	0.850	5

SERVE ANALYSIS Although it has two green squares, same as the attack, there are too many red squares to make it a reliable performance indicator.

Tour. Rank	Team	Aces	Faults	Hits	Total	S%	S% Rank	SER	SER Rank
1	Bosnia & H	32	20	493	545	2.20%	3	0.625	3
2	Iran	39	12	495	546	4.95%	1	0.308	1
3	Germany	30	26	547	603	0.66%	6	0.867	5
4	Russia	56	34	525	615	3.58%	2	0.607	2
5	Brazil	30	26	454	510	0.78%	5	0.867	5
6	Egypt	25	17	545	587	1.36%	4	0.680	4
7	China	34	31	461	526	0.57%	7	0.912	7
8	GB	28	36	323	387	-2.07%	9	1.286	9
9	Rwanda	12	19	187	218	-3.21%	10	1.583	10
10	Morocco	15	19	228	262	-1.53%	8	1.267	8
Tour. Rank	Team	Aces	Faults	Hits	Total	S%	S% Rank	SER	SER Rank
1st – 2nd		71	32	988	1091	3.57%	1	0.451	1
3rd – 4th		86	60	1072	1218	2.13%	2	0.698	2
5th – 6th		55	43	999	1097	1.09%	3	0.782	3
7th – 8th		62	67	784	913	-0.55%	4	1.081	4
9th – 10th		27	38	415	480	-2.29%	5	1.407	5

BLOCK ANALYSIS It looks like the block efficiency ratio (BER) is a good predicator of success with the block percentage not so.  The may be explained due to the fact that serves are able to be blocked.

Tour. Rank	Team	Blocks	Faults	Rebounds	Total	B%	B% Rank	BER	BER Rank
1	Bosnia & H	99	127	160	386	-7.25%	1	1.283	1
2	Iran	72	110	119	301	-12.62%	3	1.528	2
3	Germany	81	148	175	404	-16.58%	7	1.827	6
4	Russia	86	144	164	394	-14.72%	5	1.674	5
5	Brazil	88	137	167	392	-12.50%	2	1.557	3
6	Egypt	93	155	204	452	-13.72%	4	1.667	4
7	China	49	120	171	340	-20.88%	8	2.449	8
8	GB	54	99	128	281	-16.01%	6	1.833	7
9	Rwanda	24	71	87	182	-25.82%	10	2.958	10
10	Morocco	30	76	89	195	-23.59%	9	2.533	9
Tour. Rank	Team	Blocks	Faults	Rebounds	Total	B%	B% Rank	BER	BER Rank
1st – 2nd		171	237	279	687	-9.61%	1	1.386	1
3rd – 4th		167	292	339	798	-15.66%	3	1.749	3
5th – 6th		181	292	371	844	-13.15%	2	1.613	2
7th – 8th		103	219	299	621	-18.68%	4	2.126	4
9th – 10th		54	147	176	377	-24.67%	5	2.722	5

SETTING ANALYSIS Again, the assist percentage (A%) looks like to be a good performance indicator, especially distinguishing between the bottom three teams (who were really the worst three teams).

Tour. Rank	Team	Sets	Faults	Still Sets	Total	A%	A% Rank
1	Bosnia & H	216	6	434	656	32.01%	3
2	Iran	261	12	413	686	36.30%	1
3	Germany	253	14	495	762	31.36%	4
4	Russia	231	12	437	680	32.21%	2
5	Brazil	209	13	424	646	30.34%	6
6	Egypt	247	17	593	857	26.84%	7
7	China	254	13	507	774	31.14%	5
8	GB	157	11	447	615	23.74%	8
9	Rwanda	74	7	301	382	17.54%	9
10	Morocco	80	13	331	424	15.80%	10
Tour. Rank	Team	Sets	Faults	Still Sets	Total	A%	A% Rank
1st – 2nd		477	18	847	1342	34.20%	1
3rd – 4th		484	26	932	1442	31.76%	2
5th – 6th		456	30	1017	1503	28.34%	3
7th – 8th		411	24	954	1389	27.86%	4
9th – 10th		154	20	632	806	16.63%	5

RECEPTION ANALYSIS With so many red squares, reception does not look like a good performance indicator.  Even the team groupings has some orange squares in which the other skills do not have.

Tour. Rank	Team	Excellent	Faults	Recep.	Total	R%	R% Rank	ER%	ER% Rank
1	Bosnia & H	282	17	68	367	95.37%	7	76.84%	3
2	Iran	320	7	31	358	98.04%	1	89.39%	1
3	Germany	361	21	89	471	95.54%	6	76.65%	4
4	Russia	361	11	64	436	97.48%	2	82.80%	2
5	Brazil	280	22	91	393	94.40%	8	71.25%	8
6	Egypt	349	20	112	481	95.84%	4	72.56%	7
7	China	333	19	87	439	95.67%	5	75.85%	5
8	GB	305	15	85	405	96.30%	3	75.31%	6
9	Rwanda	167	30	125	322	90.68%	10	51.86%	10
10	Morocco	196	28	103	327	91.44%	9	59.94%	9
Tour. Rank	Team	Excellent	Faults	Recep.	Total	R%	R% Rank	ER%	ER% Rank
1st – 2nd		602	24	99	725	96.69%	1	83.03%	1
3rd – 4th		722	32	153	907	96.47%	2	79.60%	2
5th – 6th		629	42	203	874	95.19%	4	71.97%	4
7th – 8th		638	34	172	844	95.97%	3	75.59%	3
9th – 10th		363	58	228	649	91.06%	5	55.93%	5

DIG ANALYSIS This is the same situation with the reception, it does not look like a good performance indicator.

Tour. Rank	Team	Digs	Faults	Recep.	Total	D%	D% Rank	PD%	PD% Rank
1	Bosnia & H	220	88	214	522	83.14%	3	42.15%	3
2	Iran	265	76	152	493	84.58%	2	53.75%	1
3	Germany	207	96	266	569	83.13%	4	36.38%	6
4	Russia	179	89	222	490	81.84%	5	36.53%	5
5	Brazil	179	93	178	450	79.33%	7	39.78%	4
6	Egypt	313	92	247	652	85.89%	1	48.01%	2
7	China	191	107	285	583	81.65%	6	32.76%	9
8	GB	151	125	174	450	72.22%	10	33.56%	7
9	Rwanda	89	74	141	304	75.66%	8	29.28%	10
10	Morocco	116	94	143	353	73.37%	9	32.86%	8
Tour. Rank	Team	Digs	Faults	Recep.	Total	D%	D% Rank	PD%	PD% Rank
1st – 2nd		485	164	366	1015	83.84%	1	47.78%	1
3rd – 4th		386	185	488	1059	82.53%	3	36.45%	3
5th – 6th		492	185	425	1102	83.21%	2	44.65%	2
7th – 8th		342	232	459	1033	77.54%	4	33.11%	4
9th – 10th		205	168	284	657	74.43%	5	31.20%	5

POINT-SCORING ANALYSIS This looks like the strongest performance indicator.  The top 2 point scoring teams are ranked 1st and 2nd.  The next top 2 point scoring teams are ranked 3rd and 4th.  The worst 2 point scoring teams are ranked bottom 2.

Tour. Rank	Team	Points	Faults	Total	P%	P% Rank	PER	PER %
1	Bosnia & H	400	300	2738	3.65%	2	1.333	2
2	Iran	414	286	2665	4.80%	1	1.448	1
3	Germany	458	385	3203	2.28%	4	1.190	4
4	Russia	460	378	3018	2.72%	3	1.217	3
5	Brazil	373	329	2675	1.64%	6	1.134	6
6	Egypt	437	414	3392	0.68%	7	1.056	7
7	China	393	334	3001	1.97%	5	1.177	5
8	GB	265	307	2370	-1.77%	8	0.863	8
9	Rwanda	141	277	1595	-8.53%	10	0.509	10
10	Morocco	156	240	1714	-4.90%	9	0.650	9
Tour. Rank	Team	Points	Faults	Total	P%	P% Rank	PER	PER %
1st – 2nd		814	586	5403	4.22%	1	1.389	1
3rd – 4th		918	763	6221	2.49%	2	1.203	2
5th – 6th		810	743	6067	1.10%	3	1.090	3
7th – 8th		658	641	5371	0.32%	4	1.027	4
9th – 10th		297	517	3309	-6.65%	5	0.574	5