1. Role of cognitive bias and skill in fruit machine gambling
Professor Mark Griffiths
International Gaming Research Unit

2. THE STUDY IN CONTEXT (1988-1990)
Exploratory observational/semi-structured interview study of eight adolescent fruit machine gamblers (Griffiths, 1990a - JGS)
Semi-structured interview study of 50 adolescent fruit machine gamblers (Griffiths, 1990b - JGS; 1990c - JGS)
Case studies of adolescent fruit machine gamblers (Griffiths, BJA; JGS)
Longitudinal observational study of adolescent gamblers in amusement arcades (Griffiths, JCASP)
Postal study of ‘Parent of Young Gamblers’ members and their adolescent gambling children (Griffiths, 1993a - JGS)
Experimental study of cognition in fruit machine gamblers (Griffiths, BJP)
Experimental study of arousal in fruit machine gamblers (Griffiths, 1993b - Add.Behs)
09 November 2018

3. GLOBAL MODEL OF GAMBLING BEHAVIOUR (Griffiths, 2006; Parke & Griffiths, 2007)
09 November 2018

4. Individual Characteristics (Griffiths & Delfabbro, 2001)
09 November 2018

5. Situational Characteristics (Griffiths & Parke, 2003) Example: UK Amusement Arcade
09 November 2018

6. Structural characteristics (Griffiths, 1993;1995; Parke & Griffiths, 2001; 2007) Example: Slot machines
09 November 2018

7. COGNITIVE BIAS IN GAMBLING (Wagenaar, 1988)
“Gamblers are motivated by a way of reasoning, not by defects of personality, education or social environment”
“Gamblers gamble not because they have a bigger repertoire of heuristics but because they select heuristics at the wrong occasions”
09 November 2018

8. STUDY’S MAIN HYPOTHESES
Hypothesis 1:
There would be significant differences in the thought processes (irrational verbalisations) between regular and non-regular gamblers
Hypothesis 2:
There would be no significant differences in the (skill-based) behaviours of regular and non-regular gamblers
09 November 2018

9. IV = regular or non-regular gambler
METHOD
Quasi-experiment
Two groups of participants
IV = regular or non-regular gambler
09 November 2018

10. PARTICIPANTS 30 regular gamblers 30 non-regular gamblers
Regular (29 males & 1 female; play at least once week)
Non-regular (15 males & 15 females; play once month or less)
Volunteer Sample
Mainly recruited via a poster
09 November 2018

11. THE ‘SUBJECTIVE’ DVs (1) COGNITIVE ACTIVITY
Measured by ‘thinking aloud’
(2) PERCEPTION OF SKILL
Measured by post-experiment semi- structured interview
09 November 2018

12. THE ‘OBJECTIVE’ (BEHAVIOURAL) DVs
Total number of plays in session
Total minutes of play in session
Play rate - Total plays per minute in session
End stake – total winnings
Total number of wins in session
Win rate (time) – time between wins
Win rate (plays) – number of plays between wins
09 November 2018

13. PROCEDURE
In arcade each participant given £3 to gamble on machine that gave 30 free gambles
Objective: To stay on machine for 60 gambles
To break even and win back the £3
If they achieved 60 gambles they could choose to keep the money or carry on gambling
09 November 2018

14. CONTROLS Participants played same machine ‘FRUITSKILL’
Randomly assigned to thinking aloud/non-thinking aloud
All recordings transcribed within 24 hours
- Say everything that goes through your mind
- Do not censor your thoughts
- Keep talking continuously
- Don’t have to speak in complete sentences
09 November 2018

15. Behavioural FINDINGS: DV Non Regular NTA Regular Non TA Total Plays
Non TA
Total Plays
47.8
56.3
55.7
65.6
Total Time
8.4
8.5
11.5
9.9
Play Rate **
6.5
7.5
5.3
End Stake
4.0
7.3
13.9
Win
6.1
8.0
8.3
6.0
Win rate - time
2.0
1.0
1.7
1.8
Win rate plays **
12.5
14.6
09 November 2018

16. MAIN RESULTS (Behavioural variables)
ANOVAs showed no significant differences on all variables except:
Regular gamblers stayed on the machine slightly longer (F(1,56) = 4.27, p=0.044)
Regular gamblers had a significantly higher play rate (F(1,56) = 7.96, p=0.007)
Non-regular gamblers who thought aloud had slightly more wins than any other group (F(1,56) = 5.09, p=0.028)
Regular gamblers who thought aloud had a significantly lower win rate than any other group (F(1,56) = 7.85, p=0.007)
09 November 2018

17. MAIN RESULTS (Cognitive variables)
Content analysis of thinking aloud transcripts
31 different categories (4 irrational, 27 rational)
Regular gamblers produced significantly more irrational verbalisations than non-regular gamblers (14% vs. 2.5%; p < 0.001)
Further analysis of transcripts revealed gamblers using a variety of heuristics (e.g., hindsight bias)
09 November 2018

18. Content Analysis Examples of FINDINGS: DV Non-Regular gamblers (%)
 (%)
Machine personification
1.14
7.54 **
Explaining away losses
0.41
3.12 *
Referencing the ‘number’ system
0.90
2.64 **
Swearing at machine
0.08
0.60 *
Referencing skill
1.47
5.34 *
Verbalising confusion
(statements/questions)
4.81 **
13.24 **
1.72
1.56
09 November 2018

19. IRRATIONAL VERBALISATION
“This ‘fruity’ is not in a good mood”
“It wants its money back”
“Putting only a quid in ‘bluffs’ the machine”
“The machine thinks I am a F***wit”
“This machine won’t pay out happily”
09 November 2018

20. CONCLUSIONS
Regular gamblers are slightly more skilful (e.g. knowing the reels and when to nudge)
Regular gamblers believe they are more skilful than they are
Gamblers know they will ‘lose’ but they play with money not for it (staying on the machine is the objective)
Regular gamblers make more irrational verbalisations demonstrating cognitive bias
09 November 2018

21. e.g. by playing back their irrational thinking
APPLICATIONS?
May help to rehabilitate ‘gambling addicts’ through cognitive behavioural therapy
Can be used to help ‘problem gamblers’ change the way they think (recognise and change their cognitive bias) and behave
e.g. by playing back their irrational thinking
09 November 2018

22. EVALUATION Both quantitative and qualitative DVs
Validity the ‘thinking aloud method’??
Reliability of content analysis??
Biased sample (29 male regular gamblers) - does this matter??
Ecological validity (level of realism)
Generalisability to other forms of ‘gambling’ (e.g horse racing, dice, roulette)
09 November 2018

23. Thankyou! Any questions?
09 November 2018