Abstract | Svrha ovog istraživanja je utvrditi povezanost pokazatelja situacijske uspješnosti izvedbe pet faza odbojkaške igre s rezultatom u setovima odigranim prema službenim i prema eksperimentalnim odbojkaškim pravilima te utvrditi razlike u navedenoj povezanosti nakon promjene pravila. Uzorak entiteta za istraživanje predstavlja 80 setova od kojih je 40 odigrano prema službenim pravilima 2011. i 2012. godine, a 40 prema eksperimentalnim pravilima 2013. godine u Europskoj ligi za muškarce. Sa svake utakmice slučajnim odabirom analiziran je po jedan set. Skup varijabli je sastavljen od šest varijabli. Pet varijabli su koeficijenti uspješnosti pet faza odbojkaške igre, servisa, prijema servisa, smeča, bloka i obrane polja. Koeficijenti uspješnosti procijenjeni su na Likertovoj skali od 1 do 4 gdje 1 predstavlja minimalnu, a 4 maksimalnu vrijednost. Šesta varijabla je rezultat u setu. Rezultat u setu je definiran kao relativna bodovna razlika, odnosno bodovna razlika je podijeljena sa ukupnim brojem bodova u setu. Prema deskriptivnim pokazateljima (službena pravila) smeč je faza odbojkaške igre koja ima najveći koeficijent uspješnosti te iznosi 3,04. Iza njega slijedi prijem servisa sa gotovo podjednakim vrijednostima (2,98), zatim blok (2,29) pa servis (2,14), dok je najniži koeficijent uspješnosti zabilježen u obrani polja i iznosi 1,95. Svih pet faza odbojkaške igre kod setova odigranih prema eksperimentalnim pravilima ima gotovo podjednake koeficijene uspješnosti kao i kod službenih pravila. Od najvećeg prema najmanjem iznose: smeč (3,07), prijem servisa (2,98), blok (2,32), servis (2,14) i obrana polja (1,97). Sa strukturalnog aspekta, prema eksperimentalnim pravilima bilo je ukupno 14,6 do 18,9 % manje izvedenih tehničkih elemenata. To je u skladu sa prosječnih 16,7 % manje nadigravanja u jednome setu. Regresijskom analizom je utvrđeno da i prema službenim (R = 0,89; R2 = 80 %) i prema eksperimentalnim pravilima (R = 0,85; R2 = 73 %) postoji visoka i gotovo podjednaka povezanost faza odbojkaške igre s rezultatom u setu. Prema službenim pravilima smeč objašnjava najviše varijance rezultata u setu kao kriterija (32,6 %), slijedi mu servis (17,0 %) pa obrana polja (12,8 %) i prijem servisa (11,8 %) te na kraju blok sa svega 5,4 %. Razlike u povezanosti pokazatelja situacijske uspješnosti faza odbojkaške igre s rezultatom između dvaju pravila nisu utvrđene. Povezanost interakcija pravila i koeficijenata uspješnosti bloka te obrane polja s rezultatom se zbog veličine razlika u povezanosti s rezultatom između dvaju pravila pokazala statistički značajnim, no navedene interakcije nisu statistički značajno povećale udio objašnjene varijance rezultata te time slijedi da razlike u pravilima niti nisu statistički značajne. Povezanost koeficijenta uspješnosti bloka s rezultatom se povećala, a obrane polja smanjila. Udio zajedničke varijance bloka i rezultata se povećao sa 5,4 % na 17,2 %, a obrane polja smanjio sa 12,8 % na 4,6 %. U setovima odigranim prema eksperimentalnim pravilima dodatno se smanjila povezanost s rezultatom onih faza odbojkaške igre kojima se ne mogu osvojiti bodovi te isto tako ravnomjernije rasporedila važnost između onih kojima se može, smanjivši važnost smeča, a povećavši važnost prvenstveno bloka, ali i servisa. Upravo je promjena taktike ekipa uslijed pritiska postizanja veće bodovne razlike u ranijim fazama seta mogla uzrokovati ovakvu pojavnost. |
Abstract (english) | The purpose of this research is to determine the relationship between situational efficiency parameters of five phases of the volleyball game and a set score in the sets played by the official volleyball rules and the sets played by the experimental volleyball rules and also to determine the differences in the aforementioned relationship after changing the rules. The sample of entities is represented by 80 volleyball sets, 40 of which played according to the official rules in years 2011 and 2012 and 40 played according to the experimental rules in year 2013 in the European League for Men. A set was randomly selected from a match. The sample of variables is composed of six variables, five of which are: situational efficiency coefficient of volleyball game phases, serve, reception, spike, block and dig. The situational efficiency coefficient was estimated on the Likert scale from 1 to 4, 1 representing minimal and 4 representing maximal value. The sixth variable is a set score. The set score is defined as a relative score difference, the total score difference is divided by a total number of points in a set. According to descriptive parameters (official rules) a spike is a skill with the highest efficiency coefficient and it amounts to 3,04. Reception is second in a role with almost equal value (2,98), following block (2,29), then serve (2,14). A dig is the skill with the lowest efficiency coefficient and it amounts to 1.95. All five game phases according to the experimental rules has almost equal efficiency coefficient as the ones according to the official rules. Aligned from the highest to the lowest value, coefficients amount to: spike (3,07), reception (2,98), block (2,32), serve (2,14) and dig (1,97). Structurally, according to the experimental rules there were 14,6 to 18,9 % less skills performed. That is according to the average 16,7 % less rallies in one set. Regression analysis determined a high and almost equal relationship between five phases of the volleyball game with the set score within the official rules (R = 0.89; R2 = 80 %) and the experimental rules (R = 0.86, R2 = 74 %). According to the official rules, spike explains the highest part of variance of the set score as the criteria (32.6 %), followed by service (17.0 %), dig (12.8 %), reception (11.8 %) and finally block with only 5,4 %. Differences in the relationship between the efficiency of the five game phases with the set score between the two rules were not determined. The relationship between the interactions of the rules and the situational efficiency of the block and the dig was statistically significant. The reason to that is the size of the differences in the realationship with the score between the two rules. But the aforementioned interactions did not statistically significant increase the part of common variance of the set score so therefore the differences between the rules are not statistically significant. Within the experimental rules, the relationship between the score and the situational efficiency of the block has increased and the one with the dig has reduced. The part of common variance between the block and the set score increased from 5,4 % to 17,2 % and the dig reduced from 12,8 % to 4,6 %. The emphasis on phases that do not win the points is additionally reduced in matches played according to the experimental rules and the importance of those that do is more evenly distributed, slightly reducing the importance of spike, and increasing the importance of primarily block and then serve. The change of team’s tactics due to the pressure of achieving a higher score difference in earlier stages of set could have caused such an occurrence. |