odds - 2026 ACF Regionals

Packet G: Bonus 14

A ratio of these quantities can be directly computed, while relative risk can only be indirectly inferred from a case-control study. For 10 points each:

[10m] Name this measure of exposure–outcome association that, for a 2-by-2 contingency table, equals a times d over b times c. The log of this ratio is the dependent variable of logistic regression.

ANSWER: odds [or odds ratio; accept OR; prompt on p/(1 − p)]

[10e] Odds ratios are subject to the selection form of this phenomenon, since the selected sample does not accurately represent the population of interest.

ANSWER: bias [accept selection bias]

[10h] For a case-cohort study, relative risk approximately equals the odds ratio under this epidemiological assumption first identified by Jerome Cornfield. This assumption is unnecessary when performing “incidence-density” sampling.

ANSWER: the rare disease assumption [accept answers referring to the prevalence or incidence or probability of having the disease or outcome or condition being small; accept answers specifying that both a and c are small or negligible]

<GC, Other Science> | Packet G - McMaster A, Notre Dame C, Rutgers A, NYU A

Heard	PPB	E %	M %	H %
73	10.96	99%	11%	0%

Back to bonuses

Conversion

Team	Opponent	Part 1	Part 2	Total	Parts
Berkeley A	Berkeley C	0	0	0
Birmingham	Edinburgh B	0	10	10	E
Brandeis B	Dartmouth A	0	10	10	E
Bristol	Warwick A	0	10	10	E
Brown	Brandeis A	10	10	20	ME
CWRU A	Ohio State C	0	10	10	E
Cambridge A	Oxford A	10	10	20	ME
Carleton University	Simon Fraser	0	10	10	E
Central Florida C	Central Florida A	0	10	10	E
Chicago B	Illinois C	0	10	10	E
Chicago E	Notre Dame A	0	10	10	E
City St. George's	Southampton B	0	10	10	E
Cornell A	Cornell B	0	10	10	E
Edinburgh A	Cambridge B	0	10	10	E
Florida A	Florida C	0	10	10	E
Florida B	Central Florida B	10	10	20	ME
Georgia Tech B	Louisville B	0	10	10	E
Georgia Tech C	Alabama A	0	10	10	E
Harvard A	Harvard B	0	10	10	E
Illinois A	Purdue A	0	10	10	E
Illinois B	Chicago D	0	10	10	E
Imperial A	Manchester	0	10	10	E
Indiana A	Chicago A	0	10	10	E
Indiana C	Northwestern D	0	10	10	E
Iowa State	Georgia Tech A	0	10	10	E
LSE	Montpellier	0	10	10	E
Liberty A	Virginia	0	10	10	E
Louisville A	Alabama B	0	10	10	E
MIT	Dartmouth B	10	10	20	ME
McGill A	Ottawa	10	10	20	ME
McGill B	Western A	0	10	10	E
Michigan A	Michigan C	0	10	10	E
Michigan B	CWRU B	0	10	10	E
Minnesota A	Carleton College	0	10	10	E
Mississipi State	Vanderbilt B	10	10	20	ME
Missouri A	Missouri B	0	10	10	E
NC State B	South Carolina A	0	10	10	E
North Carolina A	James Madison B	0	10	10	E
Northwestern B	Purdue B	0	10	10	E
Northwestern C	Chicago C	0	10	10	E
Ohio State B	Michigan State	0	10	10	E
Oxford B	Cardiff	0	10	10	E
Oxford C	Imperial C	0	10	10	E
Penn State	Binghamton A	0	10	10	E
Pittsburgh	Ohio State A	0	10	10	E
RIT	Rochester	10	10	20	ME
Southampton A	Durham	0	10	10	E
Stanford A	Berkeley B	0	10	10	E
Stanford B	Berkeley D	0	10	10	E
Tennessee A	Bruin	0	10	10	E
Tennessee B	Kentucky	0	10	10	E
Texas A	Texas A&M A	0	10	10	E
Texas B	Murray State A	0	10	10	E
Toronto B	Toronto Metropolitan	10	10	20	ME
Toronto C	Brock	0	10	10	E
Toronto E	Toronto G	0	10	10	E
Toronto F	Guelph	0	10	10	E
UBC A	Western C	0	10	10	E
UC Irvine	Arizona State	0	10	10	E
UCL	Imperial B	0	10	10	E
UCLA A	UC Santa Barbara	0	10	10	E
UCLA B	UCSD B	0	10	10	E
UCSD C	UCSD A	0	10	10	E
Virginia Tech A	Duke	0	10	10	E
Virginia Tech B	Liberty C	0	10	10	E
Wake Forest	North Carolina B	0	10	10	E
Warwick B	Cambridge C	0	10	10	E
WashU A	Georgia Tech D	0	10	10	E
Washington A	Washington B	0	10	10	E
Waterloo A	UBC B	0	10	10	E
Western B	Queen's	0	10	10	E
William and Mary	North Carolina C	0	10	10	E
Yale	Southern Connecticut State	0	10	10	E

Summary

Tournament	Edition	Match	Heard	PPB	E %	M %	H %
California (North)	Main Site	✓	3	6.67	67%	0%	0%
California (South)	Main Site	✓	4	10.00	100%	0%	0%
Canada	Main Site	✓	10	12.00	100%	20%	0%
Florida	Main Site	✓	3	13.33	100%	33%	0%
Great Lakes	Main Site	✓	5	10.00	100%	0%	0%
Lower Mid-Atlantic	Main Site	✓	7	10.00	100%	0%	0%
Midwest	Main Site	✓	8	10.00	100%	0%	0%
Northeast	Main Site	✓	5	14.00	100%	40%	0%
Overflow	Main Site	✓	4	10.00	100%	0%	0%
South Central	Main Site	✓	2	10.00	100%	0%	0%
Southeast	Main Site	✓	7	11.43	100%	14%	0%
UK	Main Site	✓	12	10.83	100%	8%	0%
Upstate NY	Main Site	✓	3	13.33	100%	33%	0%