Manny and Andrew

What is Starcraft II

• RTS (real time strategy game)• Made by Blizzard entertainment• Came out in 2010• Sequel to original Starcraft (1998)• Over 5 million copies sold

Competitive Starcraft

• Starcraft is a huge competitive game• Played in large tournaments for huge cash

prizes• Played all around the world• Especially in South Korea• Starcraft II starting to gain popularity, in the

current American MLG circuit

South Korean Starcraft in a Nutshell

What we wanted to research

• See if APM was indicative of a better player (better ladder)

• What was the most played race?• How did the APM vary between the races?

Procedure

• Joined rooms of 16 people via the random matchmaking system

• Picked 2 via calculator’s random function • Looked at their 1v1 match history • Downloaded replay• Used SC2gears to analyze data

Race Distribution

2

4

6

8

10

12

14

16

18

Protoss Terran ZergRace

count

Collection 1 Bar Chart

40%

25%35%

Actions Per Minute

• APM: ‘Actions per minute’• Every time you do something (keystroke,

mouse click, etc)• http://www.youtube.com/watch?v=YbpCLqry

N-Q

APM by LeagueGrand Master

Master

Diamond

Platinum

Gold

Silver

0 50 100 150 200 250 300APM

Collection 1 Box Plot

Grand master: Left skewed, median is the center @ 181.5, Fairly tight, w/ 2 outliers, highest, range 82-260Master: Right skewed, Median is the center@157.5, largest spread, no outliers, second highest, range 79-287

Diamond: Symmetric, Mean center@ 113.14, looser spread, no outliers, third highest, range 66-178Platinum: Right skewed, median center@71 , tight spread, no outliers, fifth highest, range 580123Gold: Left skewed, median center@ 81, tightest spread, no outliers, fourth highest, range 68-81Silver: Symmetric, mean center@ 69.75, tight spread, no outliers, smallest center, range 54-83

Actions per minute by Race

Rac

e

0

1

2

3

4

5

Protoss

0

1

2

3

4

5

Terran

1

2

3

4

5

Zerg

0 50 100 150 200 250 300 350APM

Collection 1 Histogram

Protoss: Right Skewed, median as Center@144 ,bimodal, fairly tight spread, range 58-227

Terran: Right skewed, unimodal, Median center@ 126, looser spread, range 54-287

Zerg: Right skewed, median as Center@152.2, unimodal, loose spread, range 60-271

Regression Slope T-Test

,,::0

AHH

-30

-20

-10

0

10

20

0 200 400 600 800 1000 1200 1400 1600TOG_sec

0

10

20

30

40

50

60

70

0 200 400 600 800 1000 1200 1400 1600TOG_sec

Resources_Spent = 39.9TOG_sec - 7.4e+03; r2 = 0.70

Collection 1 Scatter Plot

1. Linearity Assumption 1. Yes, looks linear 2. Independence assumption 2. checked residual

plot, no pattern3. Equal variance assumption 3. no fanning/thickening

on plot X v Y4. Normal Population assumption 4. Normal prob. Plot of

residuals looks linear

Data1 Residual Plot

-400-200

0200400600800

0 20000 40000 60000 80000

Data1

Res

idua

ls

Normality Ploty = 0.9499x - 4E-16

R2 = 0.9081

-3

-2

-1

0

1

2

3

-2.371393613 -1.371393613 -0.371393613 0.628606387 1.628606387 2.628606387 3.628606387 4.628606387

Z

H0: Β = 0 (no change in resources spent) Ha: Β ≠ 0 (change in resources spent)

Conditions met T Distribution Regression slope T-Test

We reject Ho because our p-val of 1.13454x10^-11 < .05=alpha

We have sufficient evidence to say that there is a change in resources spent over the Time period of game.

GOF TestAttribute: (categorical): Race

Attribute: RaceNumber of categories: 3Alternative hypothesis: Categories of Race are not equally likely

The test statistic, chi-square, is 1.4. There are 2 degrees of freedom (one less than the number of categories).

If it w ere true that the categories of Race were equally likely (the null hypothesis), and the sampling process w ere performed repeatedly, the probability of getting a value for chi-square this great or greater w ould be 0.5.

Column Summary

Count

Protoss

Terran

Zerg

Race

14

16

10

40

Conditions:State: Check:1.SRS 1. Our

collected data was random

2.Categorical data 2. Yes, race is categorical

3.Population > 10n 3. There are more than 400 Starcraft players

4.All exp. Cell counts >5 4. Yes

Exp.

12.552

14.224

13.224

Ho: The data is consistent with a specified distribution. Ha: The data is not consistent with a specified distribution.

• We fail to reject Ho because the p-value of .556>(alpha)=.05

• We have sufficient evidence to say that our sample races matches the race distribution of all Starcraft players

T-Interval APM

Conditions:State: Check:1.SRS 1. Our

collected data was random

2.Independence 2. Assumed3.Population > 10n 3. There are

more than 400 Starcraft players

4.N>30 4. 40>30Conditions met T Distribution 1 sample T-interval

137.6 +- 2.02269 (62.1812/6.3246)INVT(2.02269)

We are 95% confident that the population mean of APM ranges from(117.713, 157.487)

Conditions:State: Check:1.SRS 1. Our

collected data was random

2.Independence 2. Assumed3.Population > 10n 3. There are

more than 400 Starcraft players

4.N>30 4. 40>30Conditions met T Distribution 1 sample T-interval

INVT(2.02269) 706.525 +- 2.02269 (334.138/6.3246)

We are 95% confident that the population mean of time of game ranges from(599.663, 813.387)

T-Interval Time of Game

Bias/Error

• Different styles of keyboard (mechanical/rubber dome/scissor switch)

• Playing a different race for a little while• Undercoverage• ‘going easy’

Personal opinions

• Manny:– Blizzard fanboy– Love the competitive scene that it spawns– Believe APM is reflective of better players– APM based on race

• Andrew– Love the game– Also believe APM is reflective of better players– APM based on race as well

Conclusions/applications to population

• APM can be a very good judgment of the skill of a player

• Most played race to be found was Terran• Highest APM was found to be Zerg• Resource spending increases over time• APM between 117.713 and 157.487 (95%

conf.)• Time of game between 599.663 and 813.387

seconds (95% conf.)

Sources

• http://sites.google.com/site/sc2gears/ • http://www.sc2ranks.com/