The magnitude of the home advantage (HA) in team sports depends on e.g., the type of sport, gender and more (cf. Gomez et al., 2021). The few studies on volleyball (overview: Paloa et al., 2021) mainly investigated female leagues (exceptions: Paloa et al., 2015; Pollard & Gomez, 2017) without assessing potential HA drivers and while being methodologically limited (e.g., small samples, neglecting nested structure). The present archival analysis examines HA at the highest level of German volleyball (men & women), including a series of COVID-19 crowd-restricted games, in a hierarchical multilevel model. We analyse how audience size (absolute & relative to capacity), travel distances, and COVID-19 affect the home team (HT) and away team (AT).
Data from volleyball-bundesliga.de on all matches from 1996 to 2021 (N=6,811, 52.8% female, HA=53%-60%) includes details on match statistics, venue, and spectator numbers. Allowing intercepts to vary between teams (2-level model), accounted for ICCmodel 0=27% of the variance. The chance of winning increased by OR=2.96, 95% CI [2.53; 3.47] when playing at home, while controlling for team strengths (OR=4.86 [4.49; 5.26], ICC=5%) and gender (ORhome:female=0.81 [0.63; 1.03]). More spectators decreased the probability of winning for HT (ORhome:spectator=0.92 [0.83; 1.01]) and even more for AT (ORaway:spectator=0.81 [0.74; 0.88]). The further AT had to travel, the lower the winning chances of HT (OR=0.91 [0.84; 0.98]). We observed similar trends for the number of sets won. These findings indicate that spectators and travelled distance drive HA less than expected (Carron et al., 2005), at least in German volleyball.