Ahh, the weighted average approach to decision making.
If you want to make a decision but don't want to trust your own intuition and judgment, and don't want to get embroiled in hard arguments where someone can get blamed later when things don't work out, then hey, I guess you need a mathematical model!
"But I only know basic arithmetic," you say.
That's okay! Because the arithmetic behind a weighted average is so easy to do and understand, anyone can do it!
Not only that, but you can take that underlying model and produce any number of pretty charts that make your entirely subjective decision seem like it has some mathematical rigor behind it!
The Weighted Average (tm): for when you absolutely have to make a completely subjective decision and don't want to be blamed for the results.
Studies have shown that often people are so clueless that weighting categories equally produces better results than their best weights.
(The study I read about asked probands to give weights for indicators of prospective university student performance (like good grades in high school, extracurricular activities, IQ, scholarships, etc), later they compared with the grades those students actually got.)
If you want to make a decision but don't want to trust your own intuition and judgment, and don't want to get embroiled in hard arguments where someone can get blamed later when things don't work out, then hey, I guess you need a mathematical model!
"But I only know basic arithmetic," you say.
That's okay! Because the arithmetic behind a weighted average is so easy to do and understand, anyone can do it!
Not only that, but you can take that underlying model and produce any number of pretty charts that make your entirely subjective decision seem like it has some mathematical rigor behind it!
The Weighted Average (tm): for when you absolutely have to make a completely subjective decision and don't want to be blamed for the results.