The influence of cognitive skills and team cohesion on player performance in Multiplayer Online Battle Arena

Tuuli Pöllänen, 15.12.2014

My intentions

1. Do cognitve skills and team cohesion relate to performance in League of Legends?

2. Which cognitive skills are relevant to gameplay in MOBAs ( + usability of GEQ and NASA TLX for game studies)

  • Implications for:
    • instrument selection for training studies
    • contribute to the tiny body of academic literature on MOBAs
    • help players and their teams understand success factors

3. Get experience building JavaScript-based web experiments ( + contribute something to jsPsych)

4. Gauge the usability of web-based methods and data for cognitive psychology game studies


The work split 

  • 20% preliminary research 

  • 60% web development

  • 20% sampling and analysis

Technical bits on GitHub:

Why research video games?

a) they involve millions of people

b) also for non-game research

  • genuine teams for research on team processes
    • ​different levels of 'teamedness'
  • intrinsically motivated experts in their native niche for computerized testing 
  • quantified level of expertise (rankings/ratings)
  • easily accessible for web-based experiments

c)  e-sports psychology

  • professional gaming is a billion dollar business
  • LoL - $8.000.000 price money/season plus yearly salary
    • rigorous training regimes, competitions, sponsorship...
    • pro gamers can benefit from psychological techniques 

League of Legends

  • Competitive free to play PvP MOBA / action real-time strategy (ARTS)
  • 67 million monthly active players, 27 million active daily

How does it work?

  • From level 1 to 30 with normal games
    • 'unranked' games against other players or AI
    • award XP and IP
  • Level 30 and access to 16 champions -> ranked games
    • solo, 3v3, 5v5
    • first 10 games for placement
      • MMR used to match with similar opponents
  1. Two teams, 3 or 5 players each
  2. 1 "champion" per player
  3. different roles:
  • carry
  • support
  • tank
  • bruiser
  • jungler

4.  kill towers, minions, monsters (jungle) and enemy champions to collect resources

5.  overpower the enemy and destroy their nexus (base)

League System

The development process


1. Exploring existing solutions

  • Java, Flash or JavaScript

2. Flash: nope.

3. Java:

  • Well researched, existing platforms for creating experiments
    • Client side Java?
      • Your Java version is out-of-date. 
      • Application Blocked
      • Application Blocked by Security Settings 
      • Your security settings have blocked an application from running with an out-of-date or expired version of Java. 
      • Your security settings have blocked an untrusted application from running.

4. JavaScript...

Creating web-based cognitive tasks in JavaScript

  • No prior research on RT accuracy
  • Only one open source platform
    • JsPsych (de Leeuw, 2014)
      • flexible plugins to create experiments (jQuery)
      • ! styling and back end are all up to you
      • I forked my own version:
        • Altered some of the features in the core
        • Wrote two plugins for my own use
        • Added some pages without jsPsych
        • NOT COMPATIBLE with recent changes to jsPsych
          • I'm working on it...

Back end

  • Node.js + Express 4.0
    • modular, easy to build on
    • Nginx as proxy 
  • Sequelize for MySQL database
    • jsPsych spits out CSV or JSON 
      • maybe experiment with MongoDB
  • ... on a DigitalOceans virtual server in San Francisco
    • SSDs!

...with very little time for sampling before the end of season 2014.

The battery

A total of ~20-30 minutes of participation:

  1. Informed consent
  2. Demographic items
  3. Group Environment Questionnaire
  4. Nasa Task Load Index
  5. Eriksen Flanker task
  6. 2D mental rotation
  7. Spatial Span
  8. Tower of London
  9. Feedback page

live at



Carron, Widmeyer & Brawley, 1985) - group cohesion in sports psychology

  • group integration - social
  • group integration - task
  • individual attractions to the group - social
  • individual attractions to the group - task

Promax PCA - task + social


Hart & Staveland, 1988 - task load inventory

  • mental demand
  • physical demand
  • temporal demand
  • performance
  • frustration
  • effort

Conflict adaptation 

Processing speed


Implementation similar to PEBL

  • fast pace, constant time between stimuli
  • 12 x 4

Mental rotation

Two-dimensional version

  • 2AFC
  • mirrored (P) or identical (Q) 
  • three stimuli
  • at 0, 60, 120, 180, 240 and 300 degrees
  • feedback between trials

Eriksen flanker

Spatial span

  • 4x4 grey grid with flashing rectangles
  • reproduce the sequence with clicking
  • decrement after two mistakes, incremented after a success
  • over after four mistakes

Tower of London

  • planning
  • how many moves (minimum) from image A to image B
  • 24 stimuli
    • between 2 and 6 difficulty


Online forums and communities:

  • MOBA fire
  • Riot Gaming boards and forums
  • Reddit League of Legends community
  • League of Legends streamers on
  • Twitter
  • Personal contact with players
  • An e-sports community in Singapore
  • No response from Riot


  • = 278, eligible = 218, finished N = 146

  • between ages 15 and 45 (M = 21.42, SD = 4.15)

Geographics by game regions:

  • North America (N=143)

  • EU-West (N=94)

  • EU-North and East (N=21)

  • Latin America (N=7)

  • New Zealand (N=8)

  • Turkey (N=2)

Play style (ranked):

  • solo queue N=206
  • 5v5 N= 51
  • 3v3 N=18

Structure in the GEQ

  • R - psych (Revelle, 2014)
  • PCA, Promax rotation, = 0.36.
  • PC1 = task-oriented, = 0.83
  • PC2 = social, = 0.79
  • Distribution of the scores is not great

PCA for cognitive tasks

  • R - psych (Revelle, 2014)
  • 4 - component varimax
  • Scoring with regression
  • No missing value imputation

Spearman's correlations, solo

Spearman correlations, team



Note - no imputation!

  • Step-wise analysis with stepAIC function in MASS R package (Venables & Ripley, 2002)
  • Best functioning models:
    • Solo rating: 
      • Flanker accuracy, planning and frustration:
        • R^2 =.16, F(3,57)=3.52, p<.05); 
          • b(RC3) = 0.22, p = 0.08
          • b(frustration) = -0.24, p = 0.06
          • b(RC4) = 0.18, p < 0.05
    • Team rating: 
      • Impossible models with TLX
      • 5v5 rating ~ task load + mental rotation:
        • R^2 = 1. , F(2,20)= 2.464e+3, <.0001
          • b(task load) = 0.99, p < 0.0001
          • b(RC2) = 0.05, < 0.0001
            • Similar model with RC3 and RC2
            • TLX is overpowering but non-significant on its own?



  1. TLX works remarkably well - effort/frustration
  2. Spatial span works remarkably unwell
  3. Participant motivation and response styles are a huge challenge

As to the intentions...

1. Do cognitve skills and team cohesion relate to performance in League of Legends?

  • Cognitive tasks appear important, but better test selection is needed
  • Check out communication style instead of team cohesion, try different conative factors 

2. Which cognitive skills are relevant to gameplay in MOBAs ( + usability of GEQ and NASA TLX for game studies)

  • Explore other cognitive skills - 3D rotation, task switching, ToL with CAT, go/no go
  • GEQ somewhat lacks discriminativeness
  • NASA TLX works great

3. Get experience building JavaScript-based web experiments ( + contribute something to jsPsych)

  • Yes. Working on the plugins.

4. Gauge the usability of web-based methods and data for cognitive psychology game studies

  • Yes - with care and certain reservations

Last things about the web experiments...


  •  All the shortcomings of web-based survey research:
    •  participant drop-out
    •  invalid responses
    •  submitting false data
    •  multiple entries
    •  self-selective sample
    •  ...
  • ... and more!
    •  invalid response times
    •  bugs (and poor bug reports)
    •  different hardware
    •  mobile access (!!)
    •  confounding environmental variables
    •  batteries are longer and strenuous than in survey research -> question of motivation
  • Great for prototyping
  • Oversample
  • Triangulate with APIs

Question of motivation


  • Bugs and poor usability:
    • drop outs
    • bad data
  • Information and feedback
  • Use adaptive testing
  • Try some gamification
  • Implement motivating features
    • login systems
    • data from API
    • spreadsheets with feedback
    • ...


Unreliable/malicious use?

  • use an ORM
  • aggregate AFTER cleaning up invalid trials
  • discard data from 'non-serious' participants
  • social network login, data from APIs
    • more reliable data
      • and more of it
    • less work for participants
    • reduces number of non-serious participants
    • anonymity?
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The influence of cognitive skills and team cohesion on player performance in Multiplayer Online Battle Arena

By tuuli

The influence of cognitive skills and team cohesion on player performance in Multiplayer Online Battle Arena

Presentation for my thesis defense

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