Exploring
the relationship between video game expertise and fluid Intelligence
A.V. Kokkinakis, P. Cowling, A., Drachen, A.R. Wade
Supplementary Material – 1
Data pre-processing
ELO/MMR ratings
After 10 placement games LoL players are assigned a Tier and a Division based on their win/loss
performance. They subsequently move up and down on that Division and move between Tiers based
on their win ratio. Tiers and Divisions therefore correspond to MMR ranges. In addition, there may
be non-linearities in MMR within and between Tiers and data in our relatively small sample do not
pass standard tests for normality. For these reasons, we show parametric statistics here only for
visualisation purposes and all correlations are computed using Spearman’s rho. We note that the
results from parametric and non-parametric analyses are almost identical.
Study 1
Rank Nonparametric correlations
We treat our data as parametric for visualisation purposes. However, League Tiers and Divisions are
not normally distributed and thus we opted for non-parametric calculations throughout our analysis.
We note that the results from parametric and non-parametric analyses are almost identical.
Study 2
All distributions were inspected for outliers and we then used Tukey’s outlier technique (k=2.2) to
identify other candidate points. Here we provide illustrations of the distributions before and after
outlier rejection.
Note all these terms in the x-axis (ELO, Matchmaking Rating, Combat_PVP) are interchangeable
(different naming conventions depending on the company) and they use win-ratio as a primary
determinant of a player’s “skill-level”.
League of Legends
S1 Fig 1 Histograms of League of Legends MMRs before (Left) and after (right) outlier rejection
Exploring the relationship between video game expertise and fluid Intelligence
A.V. Kokkinakis, P. Cowling, A., Drachen, A.R. Wade
Battlefield 3
S1 Fig 2 Histograms of Battlefield3 ELOs before (Left) and after (right) outlier rejection
Destiny
S1 Fig 3 Histograms of Destiny PVPs before (Left) and after (right) outlier rejection
DOTA 2
S1 Fig 4 Histograms of DOTA2 MMRs. No outliers were detected in this dataset