Economic efficiency is described as the ratio of economic outputs to economic inputs. This is analogous to mechanical efficiency, which is power (watts, horsepower etc.) output over power input. Since much economics these days has the look and feel of "the study of business," outputs are understood to be the goods (products and/or services) produced by a business, and inputs are understood to be things (assets) the business spends money on, evidently as means to the end of creating these products.
I propose the nomenclature "minimalist efficiency" as a measure of a type of (or perhaps a take on) economic efficiency, viewed from the consumer rather than producer POV.
For now, let's define minimalist efficiency as outputs divided by inputs as with rival efficiencies. Here's how I propose defining "minimalist output" and "minimalist input:"
Obviously, our "definition" of output is complicated and our "definition" of input is both abstract and subjective. It seems unlikely that there will soon be an empirical instrument capable of measuring quantities thus defined in scalar units such as watts, joules, pounds, shillings, ounces, etc.
So far, the approach I have taken to the problem of efficiency as a founding principle of pubwan (see PubwanIs) has come from the jargon of finance rather than economics. I have been exploring the use of efficient frontier analysis. This is a technique that has been invented apparently for negotiating between competing objectives. The textbook presentations of the subject with which I am most familiar deal with investment objectives, specifically the pursuit of income and the avoidance of risk. The concept also seems to apply to design objectives, as evidenced by the presence of optimization theory as part of the discipline of engineering.