In practice to the economist in general and to the financier in particular it is very often necessary to estimate efficiency of work of one or another system. Depending on the features of this system economic sense of efficiency can be invested in different formulas, but sense them always one is attitude of result toward expenses. A result is already got thus, and expenses are produced.

But as far as such a posteriori estimations are important?

Sure, they present a certain value for a book-keeping, characterize work of enterprise year-to-date and т. of п., but much more important for a manager in general and financial in particular to define efficiency of work of enterprise in the future. And in this case the formula of efficiency needs to be a bit corrected.

The point is that we do not know with authenticity 100% neither size of the result got in the future nor size of potential future expenses.

Appears so-called «vagueness» which we must take into account in our calculations, otherwise will simply get an incorrect decision. As a rule, this problem arises up in investment calculations at determination of efficiency of investment project (IP), when an investor is forced to define on your own on what risk he is ready to go, to get the desired result, here the decision of this twocriterion task is complicated that tolerance of investors to the risk is individual.

In general case under a risk understand possibility of offensive of some unfavorable event, entailing different sort of loss (for example, receipt of physical trauma, loss of property, receipt of profits of the below expected level et cetera).

Existence of risk is related to impossibility within 100% to forecast the future. On this basis, it is necessary to select basic property of risk: a risk takes place only in relation to the future and indissolubly related to prognostication and planning, and and with making decision in general (a word “risk” in a word for word translation means a “decision-making”, the result of which is unknown) [11]. Following aforesaid, it is needed also to mark that categories a “risk” and “vagueness” is closely constrained between itself and frequently used as synonyms.

However, an author suggests to distinguish concepts “risk” and “vagueness”.

At first, a risk takes place only in those cases, when to make decision it is necessary (if it not so, there is not sense to risk). Otherwise speaking, preeminently a necessity to make decision in the conditions of vagueness generates a risk, in default of such necessity there is not a risk.

Secondly, a risk is subjective, and a vagueness is objective. For example, objective reliable null information about the potential volume of demand on producible products results in the origin of spectrum of risks for the participants of project. For example, a risk, descendant a vagueness because of absence of marketing research for IP, applies in a credit risk for an investor (bank, financing this IP), and in the case of credit not return in the risk of loss of liquidity and further in the risk of bankruptcy, but for a recipient this risk is transformed in the risk of unforeseen vibrations of the market state of affairs., thus for each of participants of IP the display of risk is individual as in high-quality so in quantitative expression.