C. Hinsley

12 August 2020

It can often be useful to let statistical correlations drive decisions. When you're trying to maximize ROI for your efforts, drilling in on highly correlated parameters helps — many times, this is true even when no causative relationship is established. This page is a concise compilation of "primary predictors," or the main actionable effectors associated with a convincing enumeration of efforts across numerous topics.

Note that inverse correlations are listed here as well; most of the time it should be obvious if this is the case, however. If not, the linked source should be elucidative.

Education

• **Exposure to print media** is the primary predictor of declarative knowledge and deterioration of verbal abilities with age
• **Independent reading time (books)** is the primary predictor of reading achievement (comprehension, vocabulary, speed).
• Practice exam quantity is the primary predictor of grade-point average (GPA).

Health

• **Muscle mass** is the primary predictor of skeletal muscle strength (especially wrt. deterioration with age).

Productivity

• **Clutter** is the primary predictor of procrastination.

Socio-Economic Success

• **Conscientiousness (Diligence, Organization, Perfectionism, Prudence)** is the primary predictor of lifetime earnings.