Bonus
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]
<UCLA A, Other Science>
| Editions | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|
| 2 | 113 | 22.92 | 97% | 81% | 51% |
Conversion
| Team | Opponent | Part 1 | Part 2 | Part 3 | Total | Parts |
|---|---|---|---|---|---|---|
| Columbia B | Columbia A | 10 | 10 | 0 | 20 | EM |
| George Mason A | Maryland C | 10 | 10 | 0 | 20 | EM |
| Maryland A | George Mason B | 10 | 10 | 10 | 30 | EMH |
| Maryland B | NYU C | 10 | 10 | 10 | 30 | EMH |
| NYU A | George Mason C | 10 | 10 | 10 | 30 | EMH |
| Princeton | Rutgers C | 10 | 10 | 10 | 30 | EMH |
| Rowan | Lehigh A | 0 | 0 | 0 | 0 | |
| Rutgers A | Rutgers B | 10 | 10 | 0 | 20 | EM |
| Rutgers D | Johns Hopkins | 10 | 10 | 10 | 30 | EMH |
| Stony Brook | NYU B | 10 | 10 | 0 | 20 | EM |
| Vassar A | Penn | 10 | 0 | 0 | 10 | E |
| Vassar B | Lehigh B | 10 | 0 | 10 | 20 | EH |
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| UK (North) | UK | Y | 5 | 18.00 | 100% | 60% | 20% |
| UK (South) | UK | Y | 8 | 20.00 | 100% | 88% | 13% |
| Northern California | US | Y | 4 | 27.50 | 100% | 100% | 75% |
| Southern California | US | Y | 7 | 28.57 | 100% | 100% | 86% |
| Eastern Canada (1) | US | Y | 5 | 18.00 | 80% | 60% | 40% |
| Eastern Canada (2) | US | Y | 9 | 20.00 | 89% | 78% | 33% |
| Florida | US | Y | 4 | 20.00 | 100% | 50% | 50% |
| Great Lakes | US | Y | 11 | 25.45 | 100% | 82% | 73% |
| Lower Mid-Atlantic | US | Y | 9 | 22.22 | 100% | 89% | 33% |
| Upper Mid-Atlantic | US | Y | 1 | 20.00 | 100% | 100% | 0% |
| Upper Mid-Atlantic | US | Y | 9 | 24.44 | 100% | 78% | 67% |
| Upper Mid-Atlantic | US | Y | 2 | 10.00 | 50% | 50% | 0% |
| Midwest | US | Y | 9 | 25.56 | 100% | 78% | 78% |
| North | US | Y | 4 | 27.50 | 100% | 75% | 100% |
| Northeast | US | Y | 1 | 20.00 | 100% | 100% | 0% |
| Pacific | US | Y | 8 | 25.00 | 100% | 88% | 63% |
| Southeast | US | Y | 12 | 21.67 | 100% | 83% | 33% |
| Upstate NY | US | Y | 5 | 24.00 | 80% | 100% | 60% |