Time is fixed and the learning is variable, when what we need is a system that makes time variable so that the learning can be fixed.

FORBES: Clearing the Path for Learning

Besides showing that a sense of fairness has a genetic basis, this result also raises a question: why should the sense of what is fair be so variable?

ECONOMIST: Evolution

What is more, performance can be much more variable.

BBC: NHS logo

What these discussions need is the introduction of a fourth variable: The programmers using agile methodology will tell you to consider scope.

FORBES: "Release Early and Often" Only Works If You Do It

"What has precipitated the change is an increasing concern over the very variable performance of exam boards, " said a spokesman for the Independent Schools Council information service (Iscis).

BBC: Top schools' concern over exam results

So, one key variable in evaluating your mortgage, what your mortgage portfolio is worth is, No. 1, what employment is.

FORBES: Intelligent Investing

When a broker makes four times the commission placing a variable mortgage versus a fixed, what did you think is going to happen?

FORBES: Your Financial Advisor's Payday: Are Commissions Contrary to Your Financial Well-Being?

Large solar installations like what Saudi Arabia is contemplating could easily destabilize the grid if they were to consist entirely of variable PV.

FORBES: The Next Trend: Integrating PV with Solar Thermal