SEMAINE D’ETUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 121

It will suffice for our purpose to consider relationships and
eo ipso predictors that are linear. The following terms and
notations will be used throughout:

(3)

>= (Vie Vopp

A

“I

is the vector of current endogenous variables:

(4)

<= (X1p Xap --Xomt



is the vector of exogenous variables: and

(5)

2,=(V, 1s Vas ee) 5

is the vector of predetermined variables.

(.X1. Vector repression (VR-) systems

The general formula for linear vector regression is given .

'6) y, = Li(V,_15 Vio ori Xu Xo qs ...) FV;

where 1=1 ..., n; the functions L; are linear; and we assume
that L. is an eo ipso predictor of v., for all : and £,

(7)

E(ly._1 Yi
L;y,_..

In matrix representation we write the vector regression
system (6)-(7) as follows,

‘8

Mg

+

4 4

‘21 Wold - pag. 7