correlation coefficient - 2025 ACF Fall

Question

Various types of this quantity include the intra-class one and one named for Pearson, the latter of which always lies between -1 and 1. For 10 points each:

[10e] Name this quantity that measures the strength of the association between two variables. The phenomenon this quantity is named after is often incorrectly conflated with causation.

ANSWER: correlation coefficient

[10m] The square of the sample correlation coefficient is equal to the coefficient of determination in the simple form of this task. This task is commonly done using the ordinary least squares, or OLS, method.

ANSWER: linear regression [accept simple linear regression; reject “multiple regression”]

[10h] Even though correlation does not imply causation, causal claims might still be valid if there are no unobserved examples of these variables that produce spurious associations between the independent and dependent variables.

ANSWER: confounding variables [accept confounders]

Back to bonuses

Summary


Northern California	Main	Y	4	27.50	100%	100%	75%
Southern California	Main	Y	7	28.57	100%	100%	86%
Eastern Canada (1)	Main	Y	5	18.00	80%	60%	40%
Eastern Canada (2)	Main	Y	9	20.00	89%	78%	33%
Florida	Main	Y	4	20.00	100%	50%	50%
Great Lakes	Main	Y	11	25.45	100%	82%	73%
Lower Mid-Atlantic	Main	Y	9	22.22	100%	89%	33%
Upper Mid-Atlantic	Main	Y	1	20.00	100%	100%	0%
Upper Mid-Atlantic	Main	Y	9	24.44	100%	78%	67%
Upper Mid-Atlantic	Main	Y	2	10.00	50%	50%	0%
Midwest	Main	Y	9	25.56	100%	78%	78%
North	Main	Y	4	27.50	100%	75%	100%
Northeast	Main	Y	1	20.00	100%	100%	0%
Pacific	Main	Y	8	25.00	100%	88%	63%
South Central	Main	Y	6	21.67	100%	83%	33%
Southeast	Main	Y	12	21.67	100%	83%	33%
UK (North)	UK	Y	5	18.00	100%	60%	20%
UK (South)	UK	Y	8	20.00	100%	88%	13%
Upstate NY	Main	Y	5	24.00	80%	100%	60%

Data


Stanford A	Berkeley Little Prince	10	10	10	30
UCSC	Berkeley Mighty Miner	10	10	0	20
Berkeley Archer Queen	Berkeley Skeleton King	10	10	10	30
Stanford B	Berkeley Boss Bandit	10	10	10	30
Claremont A	UCSD A	10	10	10	30
Claremont C	Claremont B	10	10	10	30
UCLA C	UC Irvine	10	10	10	30
UCLA B	UCLA E	10	10	0	20
UCLA D	UCLA F	10	10	10	30
UC Santa Barbara	UCSD B	10	10	10	30
USC B	USC A	10	10	10	30
Ottawa B	McGill A	10	10	0	20
McGill B	Ottawa A	10	10	0	20
Ottawa D	McGill C	0	10	10	20
Carleton A	McGill E	10	0	10	20
Carleton B	Ottawa C	10	0	0	10
Brock A	Waterloo C	10	10	0	20
Guelph A	Toronto D	10	0	0	10
Toronto F	McMaster A	10	10	0	20
Toronto B	McMaster B	0	10	10	20
Toronto E	Toronto C	10	10	0	20
Waterloo A	Toronto G	10	10	10	30
Toronto H	McMaster C	10	0	0	10
Queen's A	Toronto I	10	10	0	20
Waterloo B	Toronto A	10	10	10	30
Florida A	South Florida A	10	10	10	30
UCF A	Florida B	10	10	10	30
ERAU Daytona A	Florida Tech A	10	0	0	10
Florida Tech B	Florida State A	10	0	0	10
Ohio State B	CWRU B	10	10	10	30
WVU B	CWRU D	10	10	10	30
Kentucky	Michigan State B	10	10	10	30
CWRU A	Louisville D	10	10	10	30
Michigan A	Michigan C	10	10	10	30
Michigan State A	Michigan D	10	10	10	30
CWRU C	Michigan State C	10	10	0	20
Michigan State D	Louisville B	10	0	10	20
Louisville A	Ohio State C	10	10	0	20
Ohio State A	Ohio State D	10	10	10	30
WVU A	Michigan B	10	0	0	10
Duke A	UNC B	10	10	10	30
JMU A	Tusculum A	10	0	0	10
William & Mary C	JMU B	10	10	0	20
Virginia A	NCSU A	10	10	0	20
Virginia Tech B	UNC A	10	10	0	20
UNC D	William & Mary B	10	10	10	30
VCU A	UNC C	10	10	10	30
Virginia Tech C	Liberty C	10	10	0	20
Virginia Tech A	William & Mary A	10	10	0	20
Columbia B	Columbia A	10	10	0	20
Rowan	Lehigh A	0	0	0	0
Rutgers A	Rutgers B	10	10	0	20
George Mason A	Maryland C	10	10	0	20
Maryland A	George Mason B	10	10	10	30
NYU A	George Mason C	10	10	10	30
Maryland B	NYU C	10	10	10	30
Princeton	Rutgers C	10	10	10	30
Rutgers D	Johns Hopkins	10	10	10	30
Stony Brook	NYU B	10	10	0	20
Vassar A	Penn	10	0	0	10
Vassar B	Lehigh B	10	0	10	20
Iowa State	Michigan Tech	10	10	10	30
Wisconsin A	Macalester	10	10	10	30
Minnesota	Wisconsin C	10	0	10	20
St. Thomas	Wisconsin B	10	10	10	30
Boston College B	Southern Connecticut State University A	10	10	0	20
Chicago A	Purdue C	10	10	10	30
Chicago B	Indiana B	10	10	10	30
Illinois Champaign	Illinois Canada	10	0	0	10
Illinois Urbana	Illinois Orange	10	10	10	30
Illinois Blue	Indiana A	10	10	10	30
WashU Grolars	Iowa B	10	0	0	10
Purdue B	Rose-Hulman A	10	10	10	30
WashU Grizzlers	Purdue A	10	10	10	30
William Woods University A	Purdue D	10	10	10	30
Alberta A	Washington Chinook	10	10	10	30
Arizona State A	Boise State	10	0	0	10
British Columbia B	Arizona State B	10	10	0	20
Washington Steelhead	British Columbia A	10	10	10	30
British Columbia C	Alberta B	10	10	0	20
Washington Coho	Texas	10	10	10	30
Washington Chum	Washington Pink	10	10	10	30
Washington Masu	Washington Sockeye	10	10	10	30
Murray State College B	Tulsa A	10	0	0	10
Nebraska A	Rose State	10	10	10	30
Tulsa B	Nebraska C	10	10	10	30
Harding	Central Oklahoma B	10	10	0	20
Chipola College	Montevallo	10	0	0	10
Georgia Tech F	Clemson B	10	0	0	10
Alabama A	Clemson C	10	10	10	30
Georgia A	Auburn A	10	10	0	20
Oklahoma	Kansas State B	10	10	0	20
Central Oklahoma A	Murray State College A	10	10	0	20
York	Durham A	10	10	0	20
Durham D	Durham C	10	0	0	10
Edinburgh C	Edinburgh A	10	10	10	30
Sheffield A	Edinburgh D	10	0	0	10
Sheffield B	Durham B	10	10	0	20
Bristol	Imperial A	10	10	10	30
Cambridge D	Cardiff	10	10	0	20
Cambridge A	Cambridge E	10	10	0	20
Imperial B	Birmingham	10	10	0	20
Imperial D	Cambridge C	10	10	0	20
Cambridge B	LSE	10	10	0	20
Southampton	Oxford	10	0	0	10
Warwick	Imperial C	10	10	0	20
Binghamton A	Cornell C	10	10	0	20
Cornell B	Cornell A	0	10	10	20
Cornell D	ESF	10	10	10	30
RIT A	Binghamton C	10	10	0	20
Rochester	RIT B	10	10	10	30
Georgia Tech A	Georgia Tech D	10	10	10	30
Clemson A	Georgia Tech B	10	10	10	30
Tennessee B	Georgia Tech E	10	10	0	20
Mississippi State A	Vanderbilt A	10	10	0	20
Auburn B	Sewanne	10	10	0	20
South Carolina A	Auburn C	10	10	0	20
Emory A	Tennessee Tech	10	10	10	30
Vanderbilt B	Tennessee A	10	10	0	20