Mathiness
Mathiness is a term for calculations and formulas that may look and feel like rigorous mathematics but lack true analytical rigor or validity, and often disregard logical coherence or factual accuracy. Carl Bergstrom and Jevin West introduced this term in the book Calling Bullshit as a way to spot bullshit.
Many estimation and scoring methods used in product management tend to fall into the category of bullshit under the definition of mathiness. This is not necessarily an issue if such methods are used informally and expecting a wide margin of error, but it can become horribly misleading and dangerous when those formulas are used expecting scientific rigour.
Many mathiness formulas resemble calculations from popular laws of physics, involving units that cannot logically be combined using basic arithmetic. In that way, fake physics formulas effectively try to convey relevance of one factor for calculating another rather than an actual calculation process.
In Calling Bullshit, the authors give the example of the Virginia Mason Quality Equation Q = [Ax(O+S)÷W] (Quality equals Appropriateness times the sum of Outcomes and Service divided by Waste), a formula used for improving operations management in healthcare. Noting that the various quantities are measured in totally different units, the authors suggest that calculating the formula mathematically doesn’t even make sense (How would outcomes and service be added? What does it mean to divide the formula by waste? In what units?).
