The Influence of Crowd Noise upon Judging Decisions in Muay Thai

doi:10.4236/ape.2012.24026

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Advances in Physical Education

2012. Vol.2, No.4, 148-152

Published Online November 2012 in SciRes (http://www.SciRP.org/journal/ape) http://dx.doi.org/10.4236/ape.2012.24026

148

The Influence of Crowd Noise upon Judging Decisions in

Muay Thai

Tony Myers1, Alan Nevill2, Yahya Al-Nakeeb1

1Newman University College, Birmingham, UK

2University of Wolverhampton, Wolverhampton, UK

Email: [email protected]

Received August 14th, 2012; revised September 15th, 2012; accepted September 30th, 2012

Background: Home advantage has been demonstrated across a number of sports, yet questions still re-

main over the causes of the phenomenon. Crowd effects on sport officials have been one mechanism

proposed in the literature. This study attempted to investigate the impact of crowd noise on home advan-

tage by examining the influence of crowd noise on the judgement decisions of Muay Thai officials.

Method: Using a repeated measures design, 10 experienced Muay Thai judges observed a video of a

Muay Thai contest in two different conditions: one with and one without crowd noise. Judges recorded

the number of strikes each competitor made using mechanical counters with a comparison made between

conditions. Results: Judges awarded 1.23 more strikes on average in the presence of crowd noise when

compared to the no crowd noise condition. Crowd noise influenced some judges greatly but other far less.

The results from a within subject ANOVA analysis suggested the differences between noise conditions

were statistically significant (F(1,39) = 4.513, P = .04, η2 = .104) as was the home advantage effect

(F(1,39) = 4.087, P = .05, η2 = .095). Conclusion: Crowd noise increased the scores of Muay Thai judges

resulting in an advantage to the home competitor. Possible reasons for the findings include informational

conformity, the use of a noise heuristic, cue learning or perceptual errors. Avenues for future research are

offered.

Keywords: Home Advantage; Crowd Noise; Decision Making; Officiating Bias; Muay Thai

Introduction

Historically, sports spectators appear to have held the belief

that they can influence performance, as early as 216 BC, Poly-

bius suggested that a cheering crowd influenced the outcome of

a boxing match (Guttmann, 1986). This belief appears to be an

enduring one. Strauss (2002) found in a survey of 10,063 spec-

tators at an American football match held in Germany, that

61.2% of those who responded felt spectators exerted a strong

influence on the outcome of American football games. Along

with the positive influence supporters’ perceive that their

cheering may have on their player’s performances, they also

presume that their taunts and boos can distract the away team

and influence referees’ decisions (Wolfson, Wakelin, & Lewis,

2005).

Home advantage research suggests that sport fans’ assump-

tions may have some foundation. Nevill, Newell and Gale

(1996) found that absolute crowd size was positively related to

the home advantage in English and Scottish soccer. They exa-

mined crowd factors associated with home advantage in Eng-

lish and Scottish soccer matches and concluded that the home

crowd influenced officials’ decisions. Home advantage appears

to decrease with referee experience, with referees of different

experience varying significantly in awarding yellow card and

penalties (Boyko, Boyko, & Boyko, 2007). The mechanism

postulated for this difference is crowd noise.

A number of researchers have chosen to use video evidence

to investigate crowd noise effects on sports officials’ decisions.

Nevill, Balmer and Williams (2002) used a quasi-experimental

design to examine if the presence or absence of crowd noise

would influence officials’ assessments of the legality of 47

challenges/incidents during a recorded English Premier League

match between Liverpool and Leicester City. The study in-

volved referees watching and assessing various tackles and

challenges recorded on videotape and found that the presence

of crowd noise had a significant effect on the decisions made

by the referees. The officials (n = 40) viewing the challenges

with background crowd noise were in close agreement with

those of the match referee and awarded significantly fewer

fouls (15.5%) against the home team when compared with

those watching in silence. The author’s found that there were

no real differences between conditions in how many times offi-

cials penalized the away team, suggesting crowd noise reduced

the number of fouls awarded against the home team rather than

increasing the number of infractions called against the visiting

team. A similar study was conducted recently by Unkelbach

and Memmert (2010) but instead of using video footage from

the same match, they instead used 56 foul scenes from 56 dif-

ferent soccer games. However, their results differed from those

of Nevill, Balmer, and Williams (2002) in that they found an

increase the number of yellow cards awarded to the away team

rather than fewer challenges awarded for the home team when

crowd noise was present.

The observed effects of crowd noise found by in a laboratory

setting have been supported by findings in a “real world” set-

ting by Pettersson-Lidbom, and Priks (2007). In 2007 the Ital-

ian government forced the football clubs that had stadiums with

deficient safety standards to temporarily play their home games

T. MYERS ET AL.

without spectators (Pettersson-Lidbom & Priks, 2007). In total

24 games were played without spectators and this allowed Pet-

tersson-Lidbom and Priks the opportunity to make a direct

comparison with games played with a crowd. They were able to

compare the decisions made by the same referee in games with

no spectators at all, and with many thousands of spectators.

They made comparisons of the number of punishments (fouls,

yellow cards and red cards) awarded by the referee. The find-

ings suggested Italian referees punished away players more

harshly and home players more lightly when the games are

played in front of spectators. The authors suggested this was

evidence of social pressure applied to officials by the crowd

who consciously modified behaviour. In a recent qualitative

study involving semi-structured interviews of five soccer refe-

rees the referees reported they did not feel the crowd influenced

them in any conscious way, but they acknowledged crowds

may influence their decisions in an indirect manner (Lane,

Nevill, Ahmad, & Balmer, 2006).

While the impact of crowd noise on officials’ decisions has

been demonstrated using different methodologies, the mecha-

nism for this is still largely speculative. Explanations for the

phenomena can be considered from different theoretical per-

spectives, with explanations ranging from social conformity to

cognitive biases. The social conformity explanation centres on

referees and judges conforming to the views of the majority of

spectators in attendance when making certain decisions. The

majority view is generally clearly discernible by a referee or

judge when officiating, particularly given a vocal partisan

crowd. Several studies conducted in a sporting context have

demonstrated that judges are influenced by conformity effects

(e.g., Scheer et al., 1983; Vanden Auweele et al., 2004; Boen et

al., 2006, 2008). These studies have focused on what has been

labelled the conformity effect or the tendency of judges to adapt

their scores to be similar to the scores of their colleague judges.

However, it could be argued that in certain circumstances

judges may adapt their scores to the views of supporters in a

similar way.

Conformity may be the result of either normative influence

or informational influence (Deutsch & Gerard, 1955). It has

been suggested that individuals’ motives for conforming in-

clude accuracy, self-related factors and other-related factors

(Pool & Schwegler, 2007). Cialdini and Goldstein (2004) im-

plied people conform because of a desire for accuracy, affilia-

tion or maintaining positive self-concept. In the case of judges

and referees it is possible that one or more of these influences

may impact on their decisions. Certainly it appears that most of

the time people have multiple motives and informational and

normative conformity occurs simultaneously (Stangor, 2004).

A number of authors have suggested motivational hypothe-

sises associated with conformity to explain for their findings.

For example, Nevill and colleagues (2002) suggested referees

award fewer fouls as they wished to avoid displeasing the home

crowd, thus conforming to the views of majority of supporters.

In a similar vein, Sutter and Kocher (2004) suggested while

soccer officials attempt to balance pleasing governing institu-

tions by being impartial with attempting to please the crowd,

home bias results from the crowd’s more immediate influence.

A plausible alternative explanation is that officials use crowd

noise as a heuristic, by providing additional information outside

of the actual evaluation criteria to simplify the judgement task.

Simon (1990) has described heuristics as “methods for arriving

at satisfactory solutions with modest amounts of computation,

(p. 11)”. These mental short cuts have been associated with the

automatic and unconscious functions of the mind. Stanovich

and West (2000) proposed that humans have two mental sys-

tems; one that is largely unconscious, automatic with a propen-

sity to makes quick intuitive decisions, and a second encom-

passes the other slower more deliberate contemplation involved

in analytic intelligence. Tversky and Kahneman (1974) demon-

strated that in particular situations the automatic intuitive sys-

tem uses a heuristic to assist in a difficult judgment, such as the

instantaneous decisions performed by sports officials.

While such heuristics play in a role in reducing the effort re-

quired by a particular task and can be beneficial in a number of

situations, they also causes predictable biases (systematic errors)

in judgement (Shah & Oppenheimer, 2008; Tversky & Kahne-

man, 1974). In making a decision, a sport official may errone-

ously place equal or more importance on the auditory informa-

tion from the crowd as they do on the visual information from

the observed action, causing a biased judgement that is influ-

enced by the vocal support of the crowd.

In combat sports such as boxing and Muay Thai, judges have

to make an assessment of the quantity and quality of blows

delivered. One of the tasks required to achieve this is to deter-

mine if a blow delivered by one contestant makes contact with

an appropriate target area on their opponent’s body. They have

to do this while at the same time assessing a blow’s effective-

ness. This is not always a straightforward task. Not only are

blows delivered very quickly but a judge’s view may also be

obstructed by corner posts, the referee or the boxers themselves.

Any of these factors lead to a level of visual ambiguity that

could allow influence by the sound information provided by a

crowd cheering on or just after delivery.

The possibility of crowd noise influencing the decisions of

Muay Thai judges is potentially greater than the effect demon-

strated on soccer referees (Nevill, Balmer, & Williams, 2002;

Pettersson-Lidbom & Priks, 2007; Unkelbach & Memmert,

2010). The average number of attacks used in an elite Muay

Thai during match has been found to be 183.5 (±27.45) (Myers

& Nevill, 2008). As such, during each round a Muay Thai

judge has to make numerous subjective decisions, deciding if a

particular blow is effective and if it strikes an appropriate target

(Myers, 2007). It is quite common to see a “home town” fighter

being cheered enthusiastically with every kick, punch, elbow or

knee delivered, whether these successfully land on target or not.

If crowd noise influences soccer referees decisions when view-

ing taped tackles. It seems a distinct possibility that the judg-

ments made by Muay Thai officials could also be influenced by

crowd noise. Balmer, Nevill, & Lane (2005) found home ad-

vantage in European championship boxing and a similar effect

may also be evident in Muay Thai as a result of crowd noise.

The aim of the present study was to explore the effect of

crowd noise on the scores awarded by qualified Muay Thai

judges and if this resulted in any home advantage effect. To do

this we used a repeated measures design similar to that used by

Balmer et al., (2007) to investigate crowd noise effects on soc-

cer referees. However, rather than investigating the influence of

noise on soccer referees, we assessed crowd noise influences on

qualified Muay Thai judges. It was hypothesised that crowd

noise would results in judges awarding inflated scores to the

contestant receiving the greater level of crowd support and this

would result in an advantage to the home competitor.

T. MYERS ET AL.

Method

Participants

Following a priori power analysis (see analysis subsection

for details), ten qualified and highly experienced Muay Thai

judges were recruited from the UK (n = 7) and Thailand (n = 3)

to take part in the present study. Institutional ethical was gained

and all participants gave their informed consent to take part in

the study prior to any testing commencing.

Test Video and Apparatus

A Muay Thai fight videoed from the perspective of a judge

from a single angle involving a fight held a stadium in Thailand

between two high ranking competitors was projected onto a

screen using a video-projection system. The eventual winner of

the bout (the home boxer) had the greatest vocal support with

the greatest number of cheers over the course of the bout (70

cheers associated with kicks, punches and knees thrown). Ne-

vertheless, to ensure a representative experimental design and

replicate what is generally the case in an actual competition

environment, the other competitor (the away boxer) did have

some crowd support (44 cheers). Noise level was measured

using a digital sound level meter at 73dB (A) at 2 m. Blows

were recorded using two mechanical hand tally counters with

the counter display covered by electrical insulation tape to ob-

scure the recorded count score from participant.

Procedure

A counterbalanced repeated measures design was used with

the judges being randomly allocated to either a noise condition

first followed by a no crowd noise condition or vice versa; no

crowd noise condition and then a crowd noise condition. This

was done to reduce the possibility of order effects. Each judge

observed the video with the crowd noise audible (the crowd

noise condition) and with a low level of white noise (no crowd

noise condition). After each round of the bout, the video was

paused and scores for each boxer recorded. There was a mini-

mum of two days between trials.

Preceding the start of the first trial instructions were read to

participants. These instructions advised the participants that

they would be watching five rounds of a Muay Thai bout twice,

in two separate trials; one after the instructions were given and

a second after a two-hour period. They were asked to register

strikes delivered by both boxers as accurately as possible using

two hand counters; one counter held their left hand and the

other in their right hand. They were informed that one counter

should be used to record the successful strikes of one boxer (red

corner boxer) and the other counter the scores of the other

boxer (blue corner boxer). They were told to do this by pressing

the relevant counter once each and every time they observed a

punch, kick, knee or elbow delivered by landing on the other

boxer’s body or head. They were advised that they would not

be informed of any of the scores they had recorded until both

trials had been completed to avoid any anchoring effect.

Participants were then given a demonstration and questioned

to determine if they understood the procedure. After this they

were told they would begin a three minute trial (one round of a

different Muay Thai bout) so they could familiarise themselves

with the procedure. Each participant watched the complete bout

(5 × 3 minute rounds) in both conditions and registered strikes

with no other participant present.

Analysis

We designed the experiment with a .8 probability of finding

a significant difference should such a difference exist in our

population of interest. To this end we conducted a priori power

test using G power 3 software to determine appropriate sample

size (Erdfelder, Faul, & Buchner, 1996) for background and a

description). Using an alpha level of .05, 1-β set at .8, with a

partial 2 .15 (an effect we considered represented a meaningful

difference). The calculation suggested ten participants were

required to achieve this. Descriptive statistics were calculated

for the noise and no noise conditions. A repeated measures

ANOVA was conducted with two within subject factors, noise

and boxer. The within subject factor noise had two levels, noise

and no noise. Similarly, the within subject factor for boxer also

had two levels; home and away. Partial eta squared was used to

determine the size of effect.

Results

There were differences in the main effect of crowd noise vs.

no noise (Table 1). However, the standard deviations were

large suggesting sizeable variations in judge’s scores (Table 1).

Interestingly, while 8 judges awarded higher scores in the

crowd noise condition, two judges awarded higher scores in the

no crowd noise condition.

The estimated marginal means between the crowd noise (M =

14.66, with 95% confidence intervals from 12.12 to 17.21) no

crowd noise (M = 13.4, with 95% confidence interval from

11.34 to 15.46) conditions suggest that in the presence of crowd

noise, judges on average awarded 1.23 more strikes than in the

no noise condition. The repeated measures ANOVA suggested

these observed difference was statistically significant for the

crowd noise conditions to a .05 alpha level (F(1,39) = 4.513, P = .04,

2 = .104). The noise-by-home vs. away boxer interaction was

also statistically significant to a .05 alpha level (F(1,39) = 4.087,

P = .05, 2 = .095).

Discussion

The presence of crowd noise did have an effect on the deci-

sions made by the qualified Muay Thai judges and this resulted

in a home advantage. Although the differences were small in

terms of a noise effect, they were statistically significant. The

partial eta squared result for the crowd noise effect suggests

that that 10.4% of the variance in the scores awarded by judges

is attributable to crowd noise, and 9.5% of the variance being

attributing to crowd noise influencing home advantage. Overall

crowd noise resulted in judges awarding 1.23 (5%) more strikes

Table 1.

The means and standard deviations of judges’ scores in noise and no

crowd noise conditions.

Conditions

Boxer

Corner No Noise Noise Difference in Means

Red 17.1 (±9.77)

15.43 (±8.18) 1.67

Blue 12.23 (±6.65)

11.38 (±5.24) .85

150

T. MYERS ET AL.

on average in the presence of crowd noise. This supported the

hypothesis that a crowd can have an influence on officiating

(Nevill & Holder, 1999; Nevill, Balmer, & Williams, 2002;

Unkelbach & Memmert, 2010) and this resulted in a home ad-

vantage, with the interaction between the boxers (home v away)

resulting in a significant effect.

We believe the absence of a real crowd means normative so-

cial conformity influences are an unlikely explanation for the

results of our study. Nevertheless, there are several possible

explanations for the findings, which while have different theo-

retical foundations. Firstly, informational conformity could

have played a role (Deutsch & Gerard, 1955). When a judge

was viewing somewhat ambiguous exchanges during the bout,

they may have used information from the crowd to help them

determine the success or otherwise of a particular blow landing.

For example, when a competitor’s body is turned away from a

judge and they see a kick initiated but not actually land, the

crowd’s cheer may well provide additional information and,

rightly or wrongly, result in that judge considering the kick to

have landed on target. Informational influence has been dem-

onstrated in judging sport previously (Boen et al., 2008) al-

though in that case the influence of other judges rather than a

crowd.

A further explanation of the findings is the possibility judges

used a “noise heuristic” (Kahnerman & Tversky, 1996). Given

judges are required to make an almost instant decision on

whether a blow landed or not, and the criteria for deciding that

can be reasonably complex, judges may well have fallen back

on schemas they had previous used by applying a “mental short

cut” with noise used alongside other signals they had learned to

associate with a scoring blow. In a similar way judges may well

have used noise as a cue, something convincingly argued for by

Unkelbach and Memmert (2010) in their recent paper. They

postulated that sports officials learn to associate particular cues

such as crowd noise to a particular decision in a particular con-

text. Arguing that judges or referees might equate similar audi-

ence reactions with different outcomes, suggesting that crowd

noise may lead to more-positive evaluations in figure skating

and conversely a higher probability of a yellow card for fouls in

soccer. In the case of the present study, judges may have

learned to equate the crowd’s cheers with a blow landing.

Interestingly there were very different responses to crowd

noise for different judges in our study. For some judges crowd

noise had the effect of increasing their scores quite dramatically,

for others a relatively small increase was observed, and yet for

two others the complete reverse was found with much higher

scores in the no crowd noise condition. While a counterba-

lanced design was employed in an attempt to minimise any

order effects, since the participant’s viewing of the same bout

was only separated by two days, anchoring bias may have im-

pacted on the results in participant’s observations in subsequent

conditions. The anchoring bias is a phenomenon in which deci-

sion makers adjust too little from their initial judgments as ad-

ditional evidence becomes available and this account for some

of the individual differences found (Tversky & Kahneman,

1974). However, that fact that crowd noise appears to have

differing effects on individual’s judgement decisions may well

be explained plausibly by individual-level factors other than

anchoring.

Decision-making performance can be influenced by differ-

ences in both the experience of making a decision and the abil-

ity to cope with affective states during decision-making (Seo &

Barrett, 2007). Certainly positive affect appears to be related to

better decision making when compared with negative affect

(Forgas, 1995; Isen, 2000). Although given the experimental

conditions it is unlikely that emotion was influential in the re-

sults of the current study. Individual differences in responses to

crowd noise are consistent with previous findings.

Research is needed in this area in an attempt made to identify

the particular factors that are involved in producing individual

decision responses to crowd noise. Lane et al. (2006) have pro-

posed a Referee Decision Scale; a 9-item scale principally de-

signed to assess individual themes and ideal-decision making

themes. We suggest that this could be used to compare referee

decisions between crowd noise and no crowd noise conditions.

This scale, and modifications of it, appears to offer the oppor-

tunity to help determine particular individual level factors in-

volved in evaluative decisions in the presence of crowd noise.

However, until more is known regarding individual differences

and crowd noise interactions and without clearly being able to

identify which judges may be vulnerable to the influence of

crowd noise, it can be argued that that Muay Thai judges should

use some form of nose cancelling earplugs to avoid the influ-

ence of crowd noise.

Before concluding, it is important to consider any methodo-

logical limitations that may have contributed to our findings.

One limitation of the present study is the fairly moderate simu-

lation of the “real-life” situation in our experimental design.

Without a real interactive crowd the possibility of normative

social conformity was reduced. It would be problematic to use

the type of repeated measures design used in the present study

during an actual live bout. However, it would be possible to

have several judges viewing several different bouts in different

conditions. This would increase validity significantly with par-

ticipants being surrounded by an actual crowd in the noise con-

dition. However, it should be noted that since external and rep-

resentative experimental design considerations are independent,

increasing the degree of such “real world” representation might

not increase external validity.

In conclusion, the results from the present study suggest that

crowd noise does affect Muay Thai judges’ decisions when

judging Muay Thai. This adds to previous findings in others

sports and point to the potential for crowd noise to contribute to

the home advantage through referee or judges’ decisions. In the

present study, judges on average awarded more points in the

presence of crowd noise and this was generally in favour of the

home competitor. Several explanations could explain this, in-

formational conformity, the use of a noise heuristic, or cue

learning where judges have previously associated crowd cheers

with a scoring blow. Equally, it may be that judges’ perceptual

accuracy was compromised by crowd noise, the differing re-

sponses the result of unidentified individual differences.

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