## Abraham Wald

Overview page. Subjects: Probability and Statistics — Economics.

(1902–50; b. Cluj, Romania; d. Travancore, India)

Hungarian geometer and statistician. Wald gained his PhD in geometry in 1931 from U Vienna. In 1938, on the Nazi seizure of...

## angel

Overview page. Subjects: Financial Institutions and Services — Computing.

An investor in a high-risk enterprise. Traditionally, the term was applied to the financial backers of stage productions but it is now used increasingly for investors in e-business.

## backward induction

Overview page. Subjects: Mathematics — Economics.

The process of solving multi-stage decision problems by finding the optimal choice in the final stage conditional on earlier choices, and then working back to the beginning taking one stage...

## base period

Overview page. Subjects: Economics — Mathematics.

The period whose data are identified with the index of 100 (sometimes 1) in constructing an index number. In the UK, for example, in 2007 official data on national income aggregates, year...

## bells and whistles

Overview page. Subjects: Economics — Computing.

Additions (such as options or warrants) made to a financial product to increase its appeal to the market.

## BLUE

Overview page. Subjects: Economics — Probability and Statistics.

(best linear unbiased estimator)

An estimator that is unbiased, is formed from a linear combination of the observations, and has the smallest variance of all such estimators.

## Box–Cox transformation

Overview page. Subjects: Probability and Statistics — Economics.

A transformation to normality suggested by Box and Sir David Cox in 1964. They proposed a family of transformations that might be used to convert a general set of *n* observations into a set...

## Box–Jenkins approach

Overview page. Subjects: Probability and Statistics — Economics.

A method of identification, estimation, and diagnostic checking of autoregressive integrated moving average (ARIMA) models. First, sample autocorrelation coefficients and partial...

## Box-Jenkins model

Overview page. Subjects: Mathematics — Economics.

A method for time-series forecasting in econometrics. It was introduced by the statisticians George Box and Gwilym Jenkins in 1970.

## competitive equilibrium

Overview page. Subjects: Economics — Mathematics.

An equilibrium state in game theory and mathematical economics achieved when agents or players act in their own interests without cooperation. Introduced by John * Nash.