a. Net Economic Welfare (NEW)
Samuelson has coined the concept of Net Economic Welfare. According to Samuelson, "Net Economic Welfare (NEW) is an adjusted measure of total national output that includes only consumption and investment item that contribute directly to economic welfare".
b. Satisfaction from leisure
As we become rich, generally, we prefer leisure to income. When we allocate more time for leisure gross national product (GNP) may come down. But welfare goes up. So when we estimate GNP, we must include satisfaction. derived from leisure by giving it a value in Net Economic Welfare.
c. Women worth at home
Women do a lot of work at home and it is not taken into account while calculating GNP. But we must include that while estimating GNP. Only then we will get a correct picture of NEW.
d. Social bads
(i) In any society, there will be some illegal activities (eg. durg trade), We should not include it in NEW They are "Social bads".
(ii) There are some underground activities those who earn huge incomes (eg. lawyers, accountants, actors) may not report actual income for tax purposes.
(iii) This unaccounted money (black money) must somehow be included in GNP estimates. Otherwise, we will get a lower figure for GNP.
(iv) During the process of economic growth there will be environmental pollution. To get NEW, we should deduct the cost of pollution from the G.N.P
(v) The concept of Net Economic Welfare has become very important in the study of National Income.

Introduction - Economics has its laws or generalization. The logical process of arriving at a low or generalization in a science is called its method. Economics uses two methods. (Deductive and Inductive).

Conclusions :
Alfred Marshall has rightly remarked "Inductive and deductive methods are both needed for scientific thought as the right and left foot are both needed for walking.

Wealth Definition: Adam Smith
(i) Adam Smith (1723 - 1790), in his book "An Inquiry into Nature and Causes of Wealth of Nations" (1776) defines "Economics c the science of wealth".
(ii) He explains how a nation's wealth is created and increased. He considers that the individual in the society wants to promote his own gain and in this process, he is guided and led by an "invisible hand".
(iii) He states that every man is motivated by his self interest This means that each person works for his own good.
(iv) Smith favours the introduction of "division of labour" to increase the quantum of output.
(v) Severe competition in factories and society helps in bettering the product.
(vi) Supply force is very active and a commodity is made available to the consumers at the lowest price.
Criticism:
(vii) For Smith, Economics consists of 'wealth-getting' activities and 'wealth-spending' activities.
(viii) An undue emphasis is given to material wealth. Wealth is treated to be an end in itself.
(ix) This view leads him to ignore human welfare as an essential part of Economics. Smith gives his definition when religious and spiritual values are held high.
(x) Ruskin and Carlyle regard Economics as a 'dismal science', "pig science" etc. as it teaches selfishness which is against ethics.

Growth definition :
Samuelson Paul Samuelson defines Economics as "the study of how men and society choose, with or without the use of money, to employ scarce productive resources which could have alternative uses, to produce various commodities over time, and distribute them for consumption, now and in the future among various people and groups of society".
The major implications of this definition are as follows:
(a) Like Robbins, Samuelson states that the means are scarce in relation to unlimited ends and that such means could be put to alternative uses.
(b) Samuelson makes his definition dynamic by including the element of time in it. Therefore, his definition covers the theory of economic growth.
(c) Samuelson's definition is applicable also in a barter economy, where money is not used.
(d) His definition covers various aspects like production, distribution and consumption.
(e) Samuelson treats Economics as a social science, whereas Robbins regards it as a science of individual behaviour of all the definitions discussed above, the 'growth' definition stated by Samuelson appears to be the most satisfactory.

Types of Utility: The following are the types of utility
(1) Form Utility: An individual consumer obtains utility from a good or service only when it is available in a particular form. Raw materials in their original form may not possess utility for a consumer. But in their changed forms as they become finished products, they provide utility to him. For example, cotton as a raw material may not possess utility for a consumer; but as it gets a new form as a cloth, it yields the consumer utility.
(2) Time Utility: A sick man derives time utility from blood not at the time of its donation, but only at the operation-time, i.e., when it is used.
(3) Place Utility: A student derives place utility from a book not at the place of its publication (production centre) but only at the place of his education (consumption centre).
(4) Service Utility: An individual consumer derives service utility from a service made available at the time when he most needs it. For example, clients obtain service utility from their lawyers, patients derive service utility from the doctors and so on.
(5) Possession Utility: When a student buys a book or dictionary from a bookseller, then only it gives utility.
(6) Knowledge Utility: It is the utility derived by having knowledge of a particular thing. Advertisement serves as a source of information on an object.