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When can we say than one society is better than another ? Nicolas Gravel (CSH - Delhi & IDEP-GREQAM (Marseille, France)

When can we say than one society is better than another ?

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When can we say than one society is better than another ?. Nicolas Gravel (CSH -Delhi & IDEP-GREQAM (Marseille, France). « The importance of the formal results lies ultimately in their relevance to normal communication, and to things that people argue about and fight for » Amartya K. Sen. - PowerPoint PPT Presentation

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Page 1: When can we say than one society is better than another ?

When can we say than one society is better than another ?

Nicolas Gravel (CSH -Delhi & IDEP-GREQAM (Marseille, France)

Page 2: When can we say than one society is better than another ?

« The importance of the formal results lies ultimately in their relevance to normal communication, and to things that people argue about and fight for »

Amartya K. Sen

Page 3: When can we say than one society is better than another ?

What are the things that people argue about and fight for ?

People argue about and fight for the defense of their private interest (much too often perhaps)

People argue about and fight for the construction of a « better » world

A better world = a world with less suffering, less exploitation, more…justice

Page 4: When can we say than one society is better than another ?

What are the things that people argue about and fight for ?

People argue about and fight for the defense of their private interest (much too often perhaps)

People argue about and fight for the construction of a « better » world

A better world = a world with less suffering, less exploitation, more…justice

Page 5: When can we say than one society is better than another ?

What are the things that people argue about and fight for ?

People argue about and fight for the defense of their private interest (much too often perhaps)

People argue about and fight for the construction of a « better » world

A better world = a world with less suffering, less exploitation, more…justice

Page 6: When can we say than one society is better than another ?

What are the things that people argue about and fight for ?

People argue about and fight for the defense of their private interest (much too often perhaps)

People argue about and fight for the construction of a « better » world

A better world = a world with less suffering, less exploitation, more…justice

Page 7: When can we say than one society is better than another ?

What are the things that people argue about and fight for ?

People argue about and fight for the defense of their private interest (much too often perhaps)

People argue about and fight for the construction of a « better » world

A better world = a world with less suffering, less exploitation, more…justice

Page 8: When can we say than one society is better than another ?

« Justice is the first virtue of social institutions, as truth is of systems of thought. A theory however elegant and economical must be rejected or revised if it is untrue; likewise laws and institutions no matter how efficient and well-arranged must be reformed or abolished if they are unjust. »

John Rawls

Page 9: When can we say than one society is better than another ?

But what is justice ? When can we say that a particular

social arrangement is « just » and another « unjust » ?

When can we say that a social institution is more just than another ?

Page 10: When can we say than one society is better than another ?

Purpose of the talk To present answers proposed by

economists to answer these questions More specifically, to present methods

used by economists to compare societies on the basis of their performance in achieving justice

Methods discussed here are robust

Page 11: When can we say than one society is better than another ?

Comparing societies ? Comparing two different societies at a

given moment (is France more just than the US ?)

Comparing a given society at different points of time (is India better now than fifteen years ago ?)

Comparing a society after a tax reform with the same society without the tax reform

etc.

Page 12: When can we say than one society is better than another ?

Comparing societies ? Society = A list of individuals Approaches focus on specific attributes

of these individuals Attributes: Income, health, education,

access to public good, etc. Comparing societies amount to

comparing distributions of these attributes across individuals

Page 13: When can we say than one society is better than another ?

Robust methods of normative appraisal ?

Method: we want it to be routinely and « easily » implementable

Based on explicit ethical principles Robustness: ethical principles that justify

the methods are widely acceptable Price to pay for robustness:

Incompleteness. The methods may fail to provide a firm answer to the questions above.

Page 14: When can we say than one society is better than another ?

Comparing societies: some examples

Comparing 12 OECD countries (+ India) based on their distribution of disposable income and some public goods

Sample of some 20 000 households in each country Disposable income: income available after all taxes

and social security contributions have been paid and all transfers payment have been received

Incomes are made comparable across households by equivalence scale adjustment

Incomes are made comparable across countries by adjusting for purchasing power differences

Page 15: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 16: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 17: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 18: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 19: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 20: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 21: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 22: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 23: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 24: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 25: When can we say than one society is better than another ?

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Page 26: When can we say than one society is better than another ?

0

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disposable income

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AustraliaFranceGermanyItalySpainswedenUKUSAIndia

Page 27: When can we say than one society is better than another ?

What are these data saying on justice ?

Except for the 10% poorest, americans in every income group have larger income than French, swedish and German. Does that mean that US is a « better » society than UK, France, or Sweden ?

Americans in every income group have larger income than British, Australians, Italians, spanish and Indians. Does that mean that US is a better society than UK, Australia, Italy, Spain or India ?

It would seem so if income was the only relevant attribute. But is that so ?

Page 28: When can we say than one society is better than another ?

Another attribute: regional infant mortality

Infant mortality (number of children who die before the age of one per thousand births) is a good indicator of the overall working of the medical system of the region where individuals live

How do countries compare in terms of the different infant mortality rate that they offer to their citizens on the basis of their place of residence ?

Page 29: When can we say than one society is better than another ?

0.005.00

10.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0065.0070.00

Number of deads per 1000

1 2 3 4 5

infant mortality groups

AustraliaFranceGermanyItalySpainSwedenUKUSIndia

Page 30: When can we say than one society is better than another ?
Page 31: When can we say than one society is better than another ?
Page 32: When can we say than one society is better than another ?
Page 33: When can we say than one society is better than another ?

Other attribute: average class size in public schools

How do the countries compare in terms of the distribution of the class sizes at public school ?

Class size: a good indicator of the school quality

Page 34: When can we say than one society is better than another ?

0.00

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1 2 3 4 5Groups of Class size

AustraliaFranceGermanyItalySpainSwedenUKUS

Page 35: When can we say than one society is better than another ?

General principles that can be derived from these comparisons Countries differ by the total amount of each

attribute they allocate to their citizens :« size of the cake »

They also differ by the way they share this cake

Less obviously, they also differ by the way they correlate the attribute between people between the different attributes

Page 36: When can we say than one society is better than another ?

2 cakes of different sizes: US & Sweden

US

Sweden

Page 37: When can we say than one society is better than another ?

Sharing the US cake

2% 4% 5%6%

8%

9%

10%12%

15%

29%

Page 38: When can we say than one society is better than another ?

Sharing the Swedish cake

4% 6%7%

8%

9%

10%11%

12%

14%

19%

Page 39: When can we say than one society is better than another ?

Our ethical principles will consider that: For a given distribution, a larger cake is

better than a smaller one Given the size, a « more equal »

distribution of the cake is better than a less equal one.

Given sizes and distributions, less correlation between cakes is better

Page 40: When can we say than one society is better than another ?

What is justice ? A welfarist answer (1) Welfarism: The only thing that matters for

evaluating a society is the distribution of welfare – happiness - between individuals

A just society is a society that maximises a function of individual happiness

Philosophical foundations: Hume, Bentham, Beccaria

Page 41: When can we say than one society is better than another ?

What is justice ? A welfarist answer (2)

Fundamental assumption: individual happiness can be measured and compared

We don’t need to know how to measure happiness but we have to accept the idea that we can measure it in a meaningful way.

Individual welfare is assumed to depend upon the individual attributes

The relationship between welfare and attributes is assumed to satisfy basic properties

Page 42: When can we say than one society is better than another ?

Specifically, we assume:

Happiness is increasing with respect to each attribute (more income makes people happier, so does more health, smaller class sizes, etc.)

The extra pleasure brought about by an extra unit of an attribute decreases with the level of the attribute (a rich individual gets less extra pleasure from an additional rupee than an otherwise identical poorer individual)

The rate of increase in happiness with respect to a particular attribute is decreasing with respect to every other attribute

Page 43: When can we say than one society is better than another ?

Which function of individual happiness should we maximize ?

Classical Utilitarianism (Bentham): the sum Modern view point: a function that exhibits

some aversion with respect to happiness-inequality

Extreme form of aversion toward happiness-inequality (John Rawls): Maxi-Min, we should focus only on the welfare of the less happy person in the society.

Page 44: When can we say than one society is better than another ?

Contrasting Maxi-min and Utilitarianism

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Contrasting Maxi-min and Utilitarianism

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Contrasting Maxi-min and Utilitarianism

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sum of income is larger in USthan in UK and in UK than inFrance

Page 47: When can we say than one society is better than another ?

Contrasting Maxi-min and Utilitarianism

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sum of income is larger in USthan in UK and in UK than inFrance but the poorest individualis richer in France than in the USor in the UK

Page 48: When can we say than one society is better than another ?

To sum up, for welfarism: 1: A society = a list of combinations of

observable attributes (one such combination for every individual)

2: Each combination of attributes is transformed into (unobservable) happiness

3: Societies are compared on the basis of their distributions of happiness

Page 49: When can we say than one society is better than another ?

Society A is better than society B if the distribution of happiness in A is considered better than that in B by any function that exhibits aversion to happiness-inequality, under the assumption that the relationship between unobservable individual happiness and obervable individual attributes satisfies the above properties (Welfarist dominance)

Page 50: When can we say than one society is better than another ?

When can we say that one society is better than another ? (the one attribute case)

n individuals identical in every respect other than the considered attribute (income)

y = (y1,…,yn) an income distribution

Q: When are we « sure » that y is « more just » than z ?

Page 51: When can we say than one society is better than another ?

Anwer no 1: Mana and Robin Hood

When y has been obtained from z by giving mana to some, or all, the individuals

When y has been obtained from z by a finite sequence of bilateral (Robin Hood) transfers, each transfer taking place between a donator that is richer than the recipient, and each transfer being insufficient to reverse the ranking of the donator and the recipient.

When y has been obtained from z by both manas and Robin Hood transfers

Page 52: When can we say than one society is better than another ?

Mana ?

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Mana ?

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Page 54: When can we say than one society is better than another ?

Robin Hood and Mana ?

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Robin Hood and Mana ?

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Robin Hood and Mana ?

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Robin Hood and Mana ?

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Robin Hood and Mana ?

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Page 59: When can we say than one society is better than another ?

Robin Hood and Mana ?

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Page 60: When can we say than one society is better than another ?

Robin Hood and Mana ?

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Page 61: When can we say than one society is better than another ?

Robin Hood and Mana ?

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Page 62: When can we say than one society is better than another ?

Answer no 2: Poverty dominance

Important issue: poverty How do we define poverty ? Basic principle: You define a (poverty)

line that partition the population into 2 groups: poor and rich

Page 63: When can we say than one society is better than another ?

2 measures of poverty

1) Headcount: Count the number (or the fraction) of people below the line

2) poverty gap: Calculate the minimal amount of money needed to eliminate poverty as defined by the line

Page 64: When can we say than one society is better than another ?

Contrasting headcount and poverty gap

Australia Austria Canada France Germany Italy Portugal Spain sweden Switz. UK USA India

4733 6815 4285 6170 5855 3554 2546 2747 5808 8679 4898 5403 789

9237 10730 8977 9555 10012 6575 4602 5407 9056 14615 8598 11025 1019

11795 12850 11935 11793 12024 8059 6110 7045 10540 17334 10883 14687 1168

14580 14725 14338 13441 13229 9438 7549 8646 11982 19806 13337 18142 1309

17377 16588 16839 15092 14857 10933 8666 10113 13371 22044 15854 21581 1462

20456 18665 19494 16966 16614 12629 10028 11656 14723 24554 18579 25206 1649

24203 20921 22382 19169 18376 14769 11415 13639 16147 27696 21574 29387 1859

28467 24042 25955 22382 21221 17342 13930 16535 18140 32095 25188 34819 2167

34592 28069 30958 26834 25201 20743 18113 20968 21091 38254 30190 43373 2694

54537 38539 44457 40175 39217 31174 32047 35457 30818 61849 49022 79030 4735

Line = 9 600

There are 2 poor in France and 1 poor in germanybut poverty gap in Germany is 3745 while it is only3475 in France

Page 65: When can we say than one society is better than another ?

Poverty dominance Problem with poverty measurement: how

do we draw the line ? Criterion: society A is better than society

B if, no matter how the line is drawn, poverty is lower in A than in B for the poverty gap (poverty gap dominance)

Page 66: When can we say than one society is better than another ?

Answer no 3: Lorenz dominance Lorenz dominance criterion: Society A

is better than society B if the total income held by individuals below a certain rank is higher in A than in B no matter what the rank is.

Easy to see with Lorenz curves. Let us draw Lorenz curves with our data.

Page 67: When can we say than one society is better than another ?

0

50000

100000

150000

200000

250000

1 2 3 4 5 6 7 8 9 10individual rank

cum

ulat

ed to

tal i

ncom

e

AustraliaFranceGermanyItalySpainSwedenUKUSIndia

Page 68: When can we say than one society is better than another ?

Cool! the 3 answers are all equivalent to the welfarist dominance answer

It is equivalent to say : society A is more just than society B for any

welfarist ethics One can go from B to A by a finite sequence

of Robin Hood transfers and/or mana Poverty gap in A is lower than in B for all

poverty lines Lorenz curve in A is everywhere above that

in B.

Page 69: When can we say than one society is better than another ?

This result is a beautiful one

Comes from mathematics: Hardy, Littlewood & Polya (1936), Berge (1959),

Adapted to economics by Kolm (1966;1969), Dasgupta, Sen and Starett (1973) and Sen (1973)

It provides a solid justification for the use of Lorenz curves

Page 70: When can we say than one society is better than another ?

Lorenz dominance chartSwitzerland US

UKAustralia

Canada

Austria

France Germany

Sweden

Italy

Spain

Portugal

India

Page 71: When can we say than one society is better than another ?

Methodology can be extended to many attributes

Same welfarist ethics Suitable generalization of poverty notions

(poverty in several dimensions) No Lorenz curves New issue: Correlation between

attributes

Page 72: When can we say than one society is better than another ?

Aversion to correlation ?

Literacy rate (%)

Income (rupees/month)400 700

40

70

500

6050

600

a red society

Page 73: When can we say than one society is better than another ?

Aversion to correlation ?

Literacy rate (%)

Income (rupees/month)400 700

40

70

500

6050

600

a red society

and a white society

Page 74: When can we say than one society is better than another ?

Aversion to correlation ?

Literacy rate (%)

Income (rupees/month)400 700

40

70

500

6050

600

a red society

and a white society

white society is more just

Page 75: When can we say than one society is better than another ?

Bidimensional dominance chartSwitzerland

USUKAustralia Canada Austria

FranceGermany Sweden

Italy

Spain

Portugal

India