SEMAINE D'ÉTUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 
machinery must be considerably modified and coordinated if 
he labour force is to accept mobility and equip itself with 
modern skills. 
Second, even where the machinery exists, we may question 
the criteria on which it operates, on which, that is, administra- 
‘ive decisions are taken. It used to be generally believed that 
optimal or near optimal decision-rules were inherent in the 
modus operandi of private enterprise. Experience has shown, 
however, that this is not always so, even if we agree to con- 
sider only private costs and benefits in determining efficiency. 
still less is it so if we consider social costs and benefits which 
the market does not value. Many writers, such as LERNER [22], 
have tried to formulate effective and mutually consistent rules 
for economic decision-making. These ideas should be followed 
1p and as far as possible put into practice. 
Third, the application of any set of administrative criteria 
presupposes an adequate flow of information to enable the con- 
trols to work properly. We must therefore examine the flow 
of information in the system and ensure that the necessary 
information is available in the right place at the right time. 
We must also keep in mind that if a system is to control itself 
oy virtue of the information that flows in it, this information 
must not be distorted by interference; if it is, the system will 
work badly, and if the interference is insistent enough, the 
system will break down altogether. A good deal of the inform- 
ation available in any economy comes from the movement of 
relative prices and costs; without such information, derived 
either from the working of the market or, in the form of 
shadow-prices, from the working of a model, the decentrali- 
sation of decisions is virtually impossible. So we should make 
‘he most of price signals as a source of information and should 
seware of fixing or changing them arbitrarily in the interest of 
some specific policy, or they will defeat their own purpose. The 
stop-and-go measures adopted by Britain in recent years for 
‘he sake of balancing the balance of payments provide a good 
® 
Stone - pag. 25