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# Consumption Patterns in Extended Families: the Role of Guests in African Economies

Benoît Rapoport

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Consumption Patterns in Extended Families:
the Role of Guests in African Economies

Benoît RAPOPORT

2000.86
Consumption Patterns in Extended Families: the Role of Guests in African Economies

Benoît RAPOPORT, TEAM<fnref n="1" />

(August 2000)

<footnote n="1">¹ TEAM, Université de Paris 1, Panthéon Sorbonne et CNRS, Maison des sciences économiques, 106-112 Boulevard de l'Hôpital, 75 647 Pais Cedex 13. Tel (33) 1 44 07 42 48. E-mail : rapopoprt@univ-paris1.fr.</footnote>
# Consumption Patterns in Extended Families: the Role of Guests in African Economies

Benoît Rapoport (August 2000)

**Abstract:** This paper proposes to explain why there are so many guests in African households and to determine the consequences on individual behaviors. The starting point is the assumption that there exists, in traditional societies, a norm, together with a system of sanctions, which states that within the family group (the extended family) everyone should receive the same share of the wealth produced by the group. The mechanism of hospitality resulting from this norm is very similar to the ultimatum game. We use a model in which people refer to a social norm which can be revised by a Bayesian process. This model of social pressure is applied when information is asymmetric, and we show how the structure of consumption is modified by the presence of guests in the household. If a part of information on expenditures of the head is private, the head will probably reduce his expenditures on goods whose consumption is observable, and increase expenditures on goods whose consumption is harder to observe, in order to not redistribute. We estimate a demand system by using a budget-consumption survey carried out in Gabon in 1994. We show that the pattern of consumption depends on the presence of guests in the household and varies with the sex and the age of the guests.

**Résumé :** Ce texte se propose d'expliquer pourquoi les membres accueillis sont si nombreux dans les ménages africains et de déterminer les conséquences de ce phénomène sur les comportements individuels. Le point de départ est l'hypothèse qu'il existe, dans les sociétés traditionnelles, une norme assortie d'un système de sanctions qui établit qu'au sein du groupe familial (la famille étendue), chacun devrait recevoir une part identique de la richesse produite par le groupe. Le mécanisme d'accueil résultant de l'application de cette norme est très similaire au jeu de l'ultimatum. Nous utilisons un modèle dans lequel les individus se réfèrent à une norme sociale pouvant être révisée par un processus bayésien. Ce modèle de pression sociale est appliqué lorsque l'information est asymétrique, et nous montrons comment la structure de consommation est modifiée par la présence de membres accueillis dans le ménage. Si une part de l'information sur les dépenses du chef est privée, celui-ci réduira certainement ces dépenses en biens dont la consommation est observable et réduira ses dépenses en biens dont la consommation est plus difficile à observer, afin d'échapper à la redistribution. Nous estimons un système de demande en utilisant une enquête budget et consommation menée au Gabon en 1994. Nous montrons que la structure de consommation dépend de la présence d'accueillis dans le ménage et varie avec le sexe et l'âge de ceux-ci.

JEL: C78, D12, D31, D64, D82.

Keywords: Intrahousehold Allocation, Family Composition, Demand Systems.

Mots-clés : Allocations intra-ménage, Composition du ménage, système de demande.
# I Introduction*

Almost half of households in Libreville and Port-Gentil (Gabon) have at least one guest. This is not specific to the Gabon: it is very common all over Africa. We define here a guest as a member of the kinship, that is, generally, brothers and sisters, nephews and nieces (see below), so a child of the head of the household, even an adult one, is never considered as a guest. Thus households are larger in African than in occidental countries not only because fertility is high, but due to differential household composition also. Our main goal is to explain the presence of these guests in the household, using a new model which we call the "social pressure model". But as African countries are among the less developed countries, it could be interesting to ask if this particular household structure has an impact on individual behavior and, *in fine*, on economic development. This paper contributes to the discussion about how consumption allocations among members of households result from the interaction of their individual behaviors. For more than a decade this debate has raised a great interest in developed economies, and has been recently extended to developing economies (see the Journal of African Economies, vol. 9, AERC supplement 1) for which the reality of extended families makes it even more relevant.

We identify the process of taking in guests with the structure of the ultimatum game. The experimental observations concerning this game can be simply described by assuming the existence of a social norm (see Lévy-Garboua and Rapoport, 2000). Redistribution within extended families is due to this norm. We assume in this paper that there are three kinds of

<footnote>* The comments of Andrew Clark, Gilles Grenêche, Shoshana Grossbard-Shechtman and Louis Lévy-Garboua are acknowledged with thanks. Earlier version of this paper were presented to the XVIIèmes Journées de Micro-économie Appliquée (juin 2000, Québec), to the June 2000 meeting of the European Society for Population Economics (Bonn, Germany) and to seminars at INRA, at INED and at TEAM. Any errors are mine alone. I also thank</footnote>
people in the household: the head, the members of the nuclear family and the guests. The latter play an ultimatum game with the head to obtain hospitality.<fnref n="1" /> Notice here that it is very important for the players of the game to have complete information at their disposal, especially about the amount to be shared. The head would certainly reduce his expenditure on goods whose consumption is observable, and increase the expenditure on goods whose consumption is hard to observe, in order to not redistribute. We test this prediction on Gabonese data by estimating a demand system. In particular, we show that the food at home share, which can be easily observed by the members of the household, decreases and the food away from home share, which is harder to observe, increases when, at a given household size, the number of guests increases.

The paper is organized as follows. Section II briefly describes the Gabonese data used afterwards. Section III proposes an overview of households in Libreville and Port-Gentil. In section IV, we present the model and some of the predictions. In section V, we test the effect of the composition of household on the structure of consumption. Section VI concludes.

## II Data

The survey we use is the last round of a budget-consumption survey carried out in Libreville and Port-Gentil, the two main Gabonese cities, between 1992 and 1994. In 1992, an exhaustive census took place in Libreville and Port-Gentil in order to build a sampling base. A

<footnote>Martin Wora and the Direction Générale de la Statistique et des Etudes Economiques (Gabon) for the access to the EBC 92-94 data.</footnote>

<footnote n="1">¹ We will use the term "hospitality" to mark out the fact of having one or several guests. It differs however from the tradition of hospitality which consists in giving room and board to relatives or friends for a few days, for example while they are traveling. Although our data do not allow us to measure it, the "hospitality" we study here usually lasts for several months, if not years.</footnote>
retrospective living standard survey was also carried out in 1993, the first since 1962.

However, for a number of reasons, this survey is not satisfactory. In 1994, a sub-sample of 636 households was surveyed, half in June-July 1994 and half in October-December 1994.

These households were followed for one month. Each member (above 16 for the girls and 18 for the boys) was given a notebook in which they noted daily expenditures and incomes. The socio-demographic data are not very extensive as the survey was mainly designed to study incomes and expenditures. One drawback is that we do not have retrospective data, so that some large purchases are probably not measured. However, this survey is quite original, as actual biological relationships between the members of the household were carefully measured. In African societies, it is often difficult to know how people are linked in the household, because of the system of kinship classifications. For example, in a patrilineal society, sons and brother's sons are referred to by the same term.

Only 412 family units are used in our study, because important information is missing
in about a third of surveyed households, particularly when the head did not fill his notebook.
In order to keep the survey representative of the population of Libreville and Port-Gentil, we
use weights computed<fnref n="2" /> on the basis of the sampling variables, assuming that no selectivity
bias arises along with the refusal to fill the notebook. Comparisons with the census show that
reweighting was necessary and a *posteriori* of good quality.

### III An overview of households in Libreville and Port-Gentil

As often in Africa, households are quite large in urban Gabon: 5.49 members on average. Several kinds of households can be distinguished. First, households can be separated by head's origin. 28.5% of households are headed by an African migrant, mainly from West

<footnote n="2">² By Gilles Grenêche.</footnote>
Africa (Mali, Senegal, Benin and Nigeria) or from Central Africa (Cameroon, Equatorial Guinea). Second, they can be classified by the sex of the head, 73.3% of households being headed by a man. Last, they can be separated by the matrimonial status of the head: 54.3% are headed by a man living with his spouse(s). A woman almost never heads a household when she is married.<fnref n="3" /> Among Gabonese one-parent households, the female heads are much more numerous than male heads (three times), although the opposite relation holds in non-Gabonese one-parent households.

The head earns, on average, 83% of the household income. This comes mainly from work in two-parent households and in non-Gabonese one-parent households headed by a man, and from transfers (from family or boy-friend) in other one-parent households. The remaining 17% is often brought by the spouse of the head. It is rare to encounter a household in which two working people co-reside, except when they are married. This is important as it means that households are built on a unique income-earner (or a unique couple). Co-residence of people working together does not seem prevalent in urban Gabon, except in certain non-Gabonese households.

As mentioned above, we know, for each member of the household, her exact ties with the head. Five variables describe this tie.

1) The "side" indicates whether she belongs either to the kinship of the head, or to the kinship of his or her spouse, or if she is a common child or grand-child.

2) The "number of wife" indicates to which wife the member is related when the head is polygamist. Notice that there are only a few polygamist households (2.2% of the

<footnote n="3">³ Here "married" just means that the spouse was present in the household when it was surveyed, although some heads say they are married, whereas they were single at the time of the survey.</footnote>
households whose head is Gabonese). However households headed by a single woman often receive gifts from the "boy-friend" of the head. As generally only the head and his or her spouse(s) earn money, there probably exists a kind of "disguised" polygamy, although the data do not allow this to be measured.

3) The "level of kinship" indicates if the subject is directly tied to the head or through another member of the household.

4) The identifier of this intermediary member.

5) The ties with either the intermediary, or the head, or his (or her) spouse(s).

So a nephew of the head will be labeled "son of the sister of the head" or "son of the brother of the head" if neither his mother nor his father is present, or "son of member x", if x (sister or brother of the head) is present.

Sub-structures are not very common in Libreville and Port-Gentil, but represent 13.7% (15.7% in households headed by a Gabonese, there is no such sub-structure in households headed by a non-Gabonese) of the members of the household, and mainly concern girls with children. There are almost no dependent men with relatives.

The head, his spouse(s) and their children and grand-children common or not<fnref n="4" /> (the "nuclear household") represent 78.2% of the members of the household (73.5% if we exclude the grand-children). This means that about one quarter of the members of the household do not belong to the nuclear household. Notice that if we exclude the children of the spouses of the head, the results we present in the empirical section do not vary very much. Other members will be called "guests" or "members of the extended family". As expected, members of the extended family are less numerous in households whose head is not Gabonese and are

<footnote n="4">⁴ This is not exceptional when the members of the main couple have children from another union than the current union.</footnote>
proportionally more numerous in one-parent households. But even in Gabonese two-parent households, head or spouses represent one quarter of the members, descendants represent about 55% of the household and extended family about 20% of the members. On the whole, there is at least one guest in 46% of the households (55% if the head is Gabonese). Guests belong to what we can call the first circle of the extended family, that is they are parents, siblings, nephews and nieces of the members of the main couple. Table 1 above describes more precisely household composition.

<table><caption>Table 1: Household composition in Libreville and Port-Gentil</caption><thead><tr><th rowspan="3"></th><th colspan="6">TWO-PARENT HOUSEHOLDS</th><th colspan="6">ONE-PARENT HOUSEHOLDS</th></tr><tr><th colspan="6">HEADED BY A</th><th colspan="6">HEADED BY A</th></tr><tr><th colspan="2">MAN</th><th colspan="2">WOMAN</th><th colspan="2">MAN</th><th colspan="2">WOMAN</th><th colspan="2">MAN</th><th colspan="2">WOMAN</th></tr><tr><th></th><th>GABONESE</th><th>NON GABONESE</th><th>GABONESE</th><th>NON GABONESE</th><th>GABONESE</th><th>NON GABONESE</th><th>GABONESE</th><th>NON GABONESE</th><th>GABONESE</th><th>NON GABONESE</th><th>GABONESE</th><th>NON GABONESE</th></tr></thead><tbody><tr><td>Heads</td><td>12,38%</td><td>25,44%</td><td>14,42%</td><td>21,84%</td><td>74,43%</td><td>21,05%</td><td>53,52%</td><td>12,38%</td><td>25,44%</td><td>14,42%</td><td>21,84%</td><td>74,43%</td><td>21,05%</td></tr><tr><td>Spouses</td><td>12,94%</td><td>25,44%</td><td>14,42%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td><td>12,94%</td><td>25,44%</td><td>14,42%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td></tr><tr><td>Sons</td><td>27,33%</td><td>20,17%</td><td>21,32%</td><td>7,98%</td><td>2,30%</td><td>15,62%</td><td>16,70%</td><td>27,33%</td><td>20,17%</td><td>21,32%</td><td>7,98%</td><td>2,30%</td><td>15,62%</td></tr><tr><td>Daughters</td><td>24,48%</td><td>19,51%</td><td>18,13%</td><td>10,90%</td><td>0,00%</td><td>26,46%</td><td>27,44%</td><td>24,48%</td><td>19,51%</td><td>18,13%</td><td>10,90%</td><td>0,00%</td><td>26,46%</td></tr><tr><td>Total nuclear family (strict)</td><td><strong>77,13%</strong></td><td><strong>90,56%</strong></td><td><strong>68,29%</strong></td><td><strong>40,72%</strong></td><td><strong>76,73%</strong></td><td><strong>63,13%</strong></td><td><strong>97,66%</strong></td><td><strong>77,13%</strong></td><td><strong>90,56%</strong></td><td><strong>68,29%</strong></td><td><strong>40,72%</strong></td><td><strong>76,73%</strong></td><td><strong>63,13%</strong></td></tr><tr><td>Other descendants</td><td>3,85%</td><td>0,40%</td><td>2,70%</td><td>5,43%</td><td>0,00%</td><td>10,46%</td><td>0,00%</td><td>3,85%</td><td>0,40%</td><td>2,70%</td><td>5,43%</td><td>0,00%</td><td>10,46%</td></tr><tr><td>Mothers</td><td>0,72%</td><td>0,40%</td><td>1,01%</td><td>1,46%</td><td>0,00%</td><td>1,11%</td><td>0,00%</td><td>0,72%</td><td>0,40%</td><td>1,01%</td><td>1,46%</td><td>0,00%</td><td>1,11%</td></tr><tr><td>Fathers</td><td>0,18%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td><td>0,46%</td><td>0,00%</td><td>0,18%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td><td>0,00%</td><td>0,46%</td></tr><tr><td>Total nuclear family (large)</td><td><strong>4,75%</strong></td><td><strong>0,80%</strong></td><td><strong>3,71%</strong></td><td><strong>6,89%</strong></td><td><strong>0,00%</strong></td><td><strong>12,03%</strong></td><td><strong>0,00%</strong></td><td><strong>4,75%</strong></td><td><strong>0,80%</strong></td><td><strong>3,71%</strong></td><td><strong>6,89%</strong></td><td><strong>0,00%</strong></td><td><strong>12,03%</strong></td></tr><tr><td>Other ascendants</td><td>0,75%</td><td>0,00%</td><td>3,04%</td><td>0,45%</td><td>0,00%</td><td>0,92%</td><td>0,00%</td><td>0,75%</td><td>0,00%</td><td>3,04%</td><td>0,45%</td><td>0,00%</td><td>0,92%</td></tr><tr><td>Younger brothers</td><td>3,91%</td><td>2,18%</td><td>8,57%</td><td>7,58%</td><td>3,75%</td><td>3,98%</td><td>0,00%</td><td>3,91%</td><td>2,18%</td><td>8,57%</td><td>7,58%</td><td>3,75%</td><td>3,98%</td></tr><tr><td>Older brothers</td><td>0,39%</td><td>0,19%</td><td>0,00%</td><td>0,60%</td><td>3,26%</td><td>0,00%</td><td>0,00%</td><td>0,39%</td><td>0,19%</td><td>0,00%</td><td>0,60%</td><td>3,26%</td><td>0,00%</td></tr><tr><td>Younger sisters</td><td>1,80%</td><td>0,21%</td><td>1,83%</td><td>9,62%</td><td>2,10%</td><td>4,61%</td><td>0,00%</td><td>1,80%</td><td>0,21%</td><td>1,83%</td><td>9,62%</td><td>2,10%</td><td>4,61%</td></tr><tr><td>Older sisters</td><td>0,24%</td><td>0,00%</td><td>0,00%</td><td>2,49%</td><td>2,30%</td><td>0,07%</td><td>0,00%</td><td>0,24%</td><td>0,00%</td><td>0,00%</td><td>2,49%</td><td>2,30%</td><td>0,07%</td></tr><tr><td>Nephews</td><td>4,21%</td><td>1,66%</td><td>4,34%</td><td>11,76%</td><td>2,30%</td><td>6,69%</td><td>2,34%</td><td>4,21%</td><td>1,66%</td><td>4,34%</td><td>11,76%</td><td>2,30%</td><td>6,69%</td></tr><tr><td>Nieces</td><td>4,73%</td><td>2,11%</td><td>6,20%</td><td>11,67%</td><td>4,60%</td><td>5,38%</td><td>0,00%</td><td>4,73%</td><td>2,11%</td><td>6,20%</td><td>11,67%</td><td>4,60%</td><td>5,38%</td></tr><tr><td>Other collaterals</td><td>2,09%</td><td>2,29%</td><td>4,02%</td><td>8,22%</td><td>4,96%</td><td>3,19%</td><td>0,00%</td><td>2,09%</td><td>2,29%</td><td>4,02%</td><td>8,22%</td><td>4,96%</td><td>3,19%</td></tr><tr><td>Total extended family</td><td><strong>18,12%</strong></td><td><strong>8,64%</strong></td><td><strong>28,00%</strong></td><td><strong>52,39%</strong></td><td><strong>23,27%</strong></td><td><strong>24,84%</strong></td><td><strong>2,34%</strong></td><td><strong>18,12%</strong></td><td><strong>8,64%</strong></td><td><strong>28,00%</strong></td><td><strong>52,39%</strong></td><td><strong>23,27%</strong></td><td><strong>24,84%</strong></td></tr><tr><td>Total</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td><td>100,00%</td></tr></tbody></table>

Guests are almost always younger than the head or than his spouses. Hospitality is almost never given to older brothers for example. Moreover, in two-parent households, the guests (the children that are not common too) are much more numerous on the side of the head and one can reject at the 5% level the hypothesis that the distribution of the "sides" are
the same in these households whether the spouse is in the labor market or not.<fnref n="5" /> This is interesting because it should mean that income is not pooled within the couple if guests are goods (because the host is altruistic toward them or because they give status or honor to the head, for example): the "distribution of guests" depends on the income distribution within the couple. Rapoport (2000a) provides a more extended description of Gabonese households.

Our main question is the following: why are there so many guests in so many households, and what are the repercussions of hospitality on individual behavior?

## IV Norm of redistribution and consumption structure

In spite of its importance, this question has not received much consideration in economic literature. Intergenerational co-residence has been studied in various parts of the world (Hayashi, 1995; Rosenzweig and Wolpin, 1985 and 1994; Amin, 1998). However, studies about what we call hospitality are almost non-existent. Inter-household in-kind or cash transfers have been studied and many tests have been conducted, but they mainly concern intergenerational transfers. For example, Beckerian altruism (Becker, 1981) has been almost always rejected.<fnref n="6" /> There is some evidence in favor of the exchange motive.⁷ However this motive is not sufficient to explain why, in Gabon, the majority of male adult guests never help, for example, in domestic tasks. Moreover, it is hard to believe that they receive hospitality because the head needs their attention.

<footnote n="5">⁵ Kolmogorov-Smirnov test of equality of distributions.</footnote>

<footnote n="6">⁶ For example, Altonji et alii, 1992 and 1997 for the United States; Bommier, 1995; Hayashi, 1995 for Japan; Cox et alii, 1998 for Peru; Rapoport, 2000b for Gabon; exceptions are Cox et alii, 1996 for Philippines; and Lee et alii, 1994 for Taiwan.</footnote>
Another assumption used to explain intra-family transfers is that risks are shared in
extended families, particularly in less developed countries where insurance markets are often
incomplete (Posner, 1980). Papers are numerous on this subject but generally concern cash
and in-kind transfers and not hospitality. Transfers can be viewed as expressions of
consumption smoothing.<fnref n="8" /> Full risk-sharing is generally rejected.<fnref n="9" /> However, there is some
evidence that people or households partly share risk.<fnref n="10" /> Hospitality could be first a way to
smooth consumption, and second a way to control the consumption of relatives as asserted by
Rosenzweig (1988) or Rosenzweig and Stark (1989).<fnref n="11" /> Note that empirical applications
mainly concern rural households, but Cox and Jimenez (1998) show that in Cartagena in
Colombia private transfers could be motivated by risk-sharing. However, they are only
interested in the extent and not in the amount of transfers.

The next section will present a new theory which tries to explain intra-family
distribution.

Norm of redistribution and ultimatum game

<footnote n="7">⁷ See Bernheim et alii (1985); Hoddinott, (1992). Cox (1987) proposes to combine altruism and exchange motive.</footnote>

<footnote n="8">⁸ See Besley (1995) for a survey on this literature in low-income countries. Of course, *ex ante* mechanisms (income smoothing) do exist too (see Morduch, 1995 for a review).</footnote>

<footnote n="9">⁹ Hayashi *et alii* (1996) for the United States; Udry (1994) for Nigeria; Townsend (1995a) for South India; and Deaton (1994) for Ivory Coast; Townsend (1995b) is an exception.</footnote>

<footnote n="10">¹⁰ See Townsend (1995a) and M. Fafchamps (1992).</footnote>

<footnote n="11">¹¹ Strictly speaking, these papers do not say anything about hospitality but argue that men marry their daughters to members of distant, dispersed but kinship-related households, first because they will be interested in the consumption of these households if they care about their daughters, and second because their daughters will be able to monitor their own households, what reduce moral hazard problems.</footnote>
We start from the assumption that there exists, in traditional societies, a norm that states that inside the family group (the extended family) everyone must receive the same share of the wealth of the group, or, to say the least, that the *ex post* incomes must not be too different. For example, among the Fang, "the rich man had in a way to pay for his security. He had therefore to show himself « very generous » (*esos*) towards one's family". "The society accepted the existence of the « rich »... provided that this « wealth », *akum*, was profitable to everybody".<fnref n="12" /> Rapoport (2000b) tries to explain this norm's origin by using a theory of coalitional games.<fnref n="13" />

As long as everyone's contribution to the production of wealth is identical<fnref n="14" />, considering the norm, nobody can, or wants to, claim more than his own contribution. However, as soon as, for instance, the productivities of agents differ, the more productive household members will experience a tension between the desire for increasing their monetary earnings and the punishment following from the breach of the norm (here, we call "norm" a rule of behavior). We do not wish to introduce new terms into the utility function such as social (as in Solow, 1990) or local (as in Frank, 1985) status, although the importance of status has often been emphasized and linked to the redistribution by ethnologists in archaic and traditional societies (see, for example Mauss, 1991). We maintain the standard assumption that people are exclusively motivated by their material payoffs, but focus on the decisional process.

Consider two group members, *I* and *S*, who differ in productivity.

<footnote n="12">¹² Bot Ba Njock (1960) quoted, page 140, by Balandier (1982 [1955]).</footnote>

<footnote n="13">¹³ See also Lindbeck *et alii* (1999); Lindbeck (1997); Bernheim (1994); Elster (1989); and Akerlof (1982).</footnote>

<footnote n="14">¹⁴ We suppose, here, to simplify, that the production of the group is the sum of the individual productions, although externalities exist, for example, in the farm activities.</footnote>
If, at first, *S*, who is more productive than *I*, does not know it, he will not redistribute. But, if, subsequently, *I* tells *S* that he earns less than him, perhaps either because he is jobless, because his own parents have done worse than his, or because he is not as gifted as *S*, implicitly, *I* reminds *S* of the sharing rule. *S* may then either accept and propose a transfer to *I*, or refuse to redistribute, and thus undergo the sanction, for example a loss of utility *D*, which could depend on the size of the group *n*. For instance, he could be excluded from the group, be kept out of the pool of risk-sharing, suffer a magical vengeance<fnref n="15" />, or feel guilty or shameful if the norm has been internalized.

The reasons why people conform to a norm are numerous (see, for example, Elster, 1989 or Kreps, 1997). Posner (1997) describes four incentives for obeying norms: some norms are constitutive of advantageous transactions and thus self-enforcing; some are enforced by the emotions; some are enforced by expressions of disapproval, and sometimes by ostracism; some of them are internalized and obeyed out of a sense of guilt or shame. When the norm is bad, this last reason raises an important problem, as internalization reduces the set of possibilities.

To simplify, without modifying the analysis, we assume that *I* has no income, and that the income of *S* is exactly *D*. *S* makes a proposal to *I* on how to share *D*. *I* has the opportunity to either accept or reject the offer. In the latter case, he informs the group, receives nothing, but *S* is punished, exactly as if he had refused to share.<fnref n="16" /> If *I* accepts the proposal, *D* is shared

<footnote n="15">¹⁵ De Rosny (1995) shows that in Douala group (Cameroon), there is always a responsible for a misfortune, an illness. He or she is generally a relative and often among the closest. The role of the sorcerer (*nganga*) is to find him.</footnote>

<footnote n="16">¹⁶ Notice that we suppose here that all individuals have the same power in the group. Actually, it is seldom the case, and there are often heterogeneities in the group concerning the power (see Laruelle, 1999), which could be or not correlated with income heterogeneities. The most</footnote>
according to it. The rest of the group plays the role of the norm enforcer. We thus accept the
third reason why people obey norms according to Posner (1997). The norm of redistribution
may be internalized, but we do not think that it is the main incentive for obeying it. There
exists a norm enforcer, the group, which has a large range of punishment at its disposal, from
peer reprobation to ostracism or even death. Even though the members of the group are not
paid for enforcing the norm and there is a potential free-rider problem, Posner suggests that
they actually do it in order to avoid the future costs of dealing with the norm-violator. Thus,
the norm will be more efficient if the size of the group is small, particularly because a norm-
violator is more easily identified. For example, among the Fang, there is no hierarchical
organization, no centralization of the power, but there are a lot of courts: a family court, a
court of principal lineage, and a clan court (Balandier, 1982).

In this perspective, the group exerts a pressure on its members. We call it "social
pressure". It differs from but is related to "peer pressure" (Kandel and Lazear, 1992) in the
sense that the group incites its members to adopt a particular behavior.

The structure of the problem we have just described is similar to the ultimatum game.

Güth *et alii* (1982) first implemented the ultimatum game. This two-player game is quite simple. The first player (the proposer) proposes how to divide a given sum of money (the cake) with the second player (the responder), who has the opportunity to refuse the offer. Without loss of generality, the sum can be normalized to one. If the responder refuses, both players receive nothing. If he accepts, the cake is distributed according to the proposal. This game has a unique subgame perfect equilibrium: player 1 proposes to keep all the cake, or

powerful could then refuse to redistribute without suffering the punishment, except if the
norm has been internalized.
almost all if there is a smallest monetary unit, and player 2 must accept. However the experimental results sharply contrast with these predictions. First, there is practically no offer above 0.5; second, a very large majority of offers lie in the interval [0.4, 0.5]; third, there is almost no offer below 0.2; and, last, low offers are frequently rejected and the probability of rejection decreases with the share offered (see table 1 in Fehr and Schmidt, 1999). These regularities continue to hold for high stake sizes (Hoffman *et alii*, 1996).

Lévy-Garboua and Rapoport (2000) explain why agents exploit their bargaining power in competitive markets but not in bargaining situations like the ultimatum game. This paper offers a common framework to explain why people behave differently in both kinds of situations. Instead of introducing new arguments in the utility function like inequity aversion or altruism, they propose to describe the decisional process of the agent. They suppose that, before playing, players stand behind a veil of ignorance and refer to a social norm that constitutes a common prior. Once the game has begun, a player can modify his initial choice depending on the new information he received, for example the position that was assigned to him. This model can be used to describe the redistribution inside the extended family. More precisely, here we are interested in a particular sort of in-kind transfers: hospitality to the numerous guests who live in a lot of Gabonese households. We think that the model we have just described above could explain rather well why there are so many guests in Gabonese households.

## A model of redistribution with asymmetric information

We can now derive some testable predictions from this model of redistribution. The actual situation is more complex than a simple ultimatum game. In fact there exists a serious problem of asymmetric information. Recall that the outcomes observed in laboratory experiments differ somewhat depending on whether the size of the cake is common
knowledge or not. In the ultimatum game, the division generally concerns the part of the cake known with certainty, that this amount is in most cases equally shared and that the offers are usually accepted.<fnref n="17" /> These differences should be observed in the extended family.

Consider a young man or girl. We suppose that everyone knows his own and his parents' productivity, but have only imprecise information about the productivity of other kinship members (siblings, cousins, uncles or aunts...). Some of this information has to be observable. For example, he can roughly infer the income of his uncle from the area of exploited land if his uncle is a farmer. In an urban environment, the individual often knows the occupation of his kinship members. But, if it is quite easy to know approximately the income of a state employee, it is much harder if the relative works in the private sector or is self-employed.<fnref n="18" /> Moreover, some possessions indicate the level of income: in a developing country, a private car often indicates a relatively high income, a position with a car (there are many in Gabon) shows the importance of the position in the public sector. A big house can indicate whether one lives comfortably. Therefore, the individual has some information on his relatives' wealth, yet it is often insufficient to infer it exactly. However, especially in town, as the job-research costs are generally positive, a young man has almost always a relative who earns more than he does. Notice that it was easy for a young Gabonese to find a job in the public sector until 1986. In 1986, the difficulties began for oil-producers<fnref n="19" />, and it became less easy. Even before 1986, however, one did not obtain a job immediately. Consequently, it is

<footnote n="17">¹⁷ See Güth *et alii* (1996). More specifically, they described a two-level ultimatum game with incomplete information (see also Straub and Murnighan, 1995; and Mitzkewitz and Nagel, 1993).</footnote>

<footnote n="18">¹⁸ That is partly why, in agricultural societies, the tasks are collective, and why the lack of privacy is very frequent. Cureau (1912) writes that, in Gabon, "the village is an Argus to whom nothing escapes." (quoted by Pourtier, 1989, page 161).</footnote>

<footnote n="19">¹⁹ See Hugon (1989) for example.</footnote>
more than probable that our young subject will place a claim for redistribution with a wealthier relative. He will not, of course, appeal to anybody. First of all, the observed income of his partner have to be high enough; second, this relative must be close enough, otherwise, the threat of punishment will not be credible. More exactly the norm must be effective.<fnref n="20" />

Consumption often offers the economist an accurate measure of individual or household income; this holds for relatives too. However, the consumption of certain kinds of goods is more difficult to observe than others. Clearly, nonexcludable rival goods form the first source of sharing, precisely because they are not excludable. Then, food at home will be shared among household members, including our subject; the same is true for the housing. That is why we often observe among the African extended family in-kind transfers rather than cash transfers. The basic altruism model can not explain why in-kind transfers take place, although Bruce and Waldman (1991) show that in-kind transfers are an efficient solution to the Samaritan Dilemma. This kind of transfer, especially the accommodation of relatives, has not aroused the attention of economists, perhaps because it is difficult to quantify, but also because of a certain reluctance to consider the household as other than a single unit.

The results of Güth *et alii* (1996) seem to be in harmony with what is observed in Gabonese families. The host only shares what his relatives can observe from his income. Food

<footnote n="20">²⁰ Mahieu, (1992) proposes a model of pressure that shares some features with our. For him, members of African societies belongs to several communities that impose on them obligations that can be exchange for rights, particularly because they have a taste for social status. They satisfy their obligations before choosing their consumption, labor supply and so on. However we show here how choices can be manipulated. Although Mahieu's model leaves unanswered several important questions (time consistency, origin of the rights and obligations and of the concern for social status), his great merit is that it empathizes the importance of considering</footnote>
and housing are redistributed more because they are easily observed, than because they are essential for life.

What are the repercussions on labor supply, investment and consumption structure? First of all, the host will try to hide the largest possible share of his income and expenditures. We can then predict that observable consumption (here nonexcludable goods) will be substituted for rival and excludable goods (private goods), only because if a good has to be shared, its price increases for the host. Accommodation of guests is then equivalent to an *ad valorem* tax. Therefore, for example, we can predict that, after controlling for the size of the household and the composition by age and sex, the budget share of food at home will decrease with the number of guests, and the budget share of food away from home will increase with the number of guests.<fnref n="21" />

Moreover, if the income-effect is not too important, the demand for leisure should be higher in the taxed families and thus labor supply should be lower. Besides, if we are interested in the dynamics, we should observe a general disincentive to invest in human capital. In fact, a high level of education signals an individual as having high income and the return on the investment is always taxed, because of redistribution.

In the next section, we consider a household in which one or several guests are living. We show that under certain conditions, the demand for goods whose consumption is easy to observe decreases with the number of guests, at a given household size.

individual in their family (or other) networks and that it is hard to understand Africans' behavior without taking this point into account.

<footnote n="21">²¹ Notice however that it is not possible to hide completely the consumption of food (how to pretend not to eat?); moreover the price of a calorie is often higher away from home than at home.</footnote>
## Redistribution and consumption structure

Consider a household with $n$ members ($n \ge 2$). Among the members, there is a share $t$ of relatives $t \in \{i/n, i = 1, \dots, n-1\}$. The others belong to the nuclear family of the household head, namely the head, his spouses and their children.<fnref n="22" />

**Assumption 1:** the head is altruistic toward the members of his nuclear family: his utility function depends positively on their well-being (Becker, 1981). To simplify, we also assume that he is the only money-earner in the household, although this assumption is not fundamental (it eliminates corner-solutions).

**Assumption 2:** there are two kinds of goods, besides leisure: goods (type 1) whose consumption can be easily observed, private but nonexcludable goods, like food at home and housing, and goods (type 2) whose consumption can be hidden, but that cannot be shared with the nuclear family, if hidden, like drinks or food away from home.

**Assumption 3:** because of the norm of redistribution, the head must redistribute his income to the guests, but only that which can be observed, that is good 1.

### Note on assumption 1:

We chose to describe the mode of wealth distribution within the nuclear household by using the Beckerian model of altruism. Of course, this choice can be criticized. Many theoretical and empirical works cast doubt on what is generally called the unitary model.<fnref n="23" /> In

<footnote n="22">²² In Gabon, women are often head of household, but almost never when they live with their spouses (see above). That is why we wrote "His spouses".</footnote>

<footnote n="23">²³ See, for example, Chiappori (1988 and 1992); Manser and Brown (1980); McElroy and Horney (1981); Lundberg and Pollak (1993 and 1994), who offer alternative theoretical</footnote>
fact, we think that the model of altruism is not too bad an approximation of the relationships
between parents and children. The problem is more serious if we consider the ties between
spouses (see section III, too); but it is pretty hard to deal with three or more types of household
members. That is why we focus on the differences between nuclear household and guests and
why we simply model the nuclear household as a unit. However, in the empirical work we
used different measures of the nuclear household, and the results are very robust.

If the norm states that the income should be equally divided, each guest receives an $n^{th}$
of the expenditures on good 1. After this tax, the head allocates the remainder among the
members of the nuclear household, in accordance with the process described in Becker. In
fact, if player 1 has obtained his position because of his capacities, he should demand a more
than equal share. Then, each guest receives not exactly $C_1/n$ where $C_1$ is the expenditure on
good 1, but $C_1/k(n)$ where $k(n) \ge n$. Nevertheless, to simplify, we assume here that $k(n) = n$;
the qualitative results do not differ if $k(n) > n$.

As the members of the nuclear household, except the head, cannot take advantage of
good 2, their utility function depends only on good 1. We suppose that the functions that
represent the ophelimities<fnref n="24" /> of the agents are identical<fnref n="25" /> and that the utility function of the
head of household is separable (functional separability) in his own ophelimity and in the
utilities of the members of the nuclear family. Moreover, we assume that the preferences are
separable in consumption of good 1 in one hand and in consumption of good 2 and leisure in

models. Bourguignon *et alii* (1993); Browning *et alii* (1994); Fortin and Lacroix (1997); Udry (1994), Lundberg *et alii* (1997); or Thomas (1990) propose empirical tests. There exist several surveys on this subject. The more recent is Strauss *et alii* (2000).

<footnote n="24">²⁴ The utility that a subject derives from his own consumption.</footnote>

<footnote n="25">²⁵ This assumption is not fundamental.</footnote>
the other hand. Notice that this technical assumption can be justified as it is often easier to
separate leisure from food at home than from food away from home.

## Description of the household and notation

There are $n$ members in the household. A $t$-proportion of them belong to the extended-family and, then, are viewed as guests. There are thus $tn$ guests, and the nuclear household has $(1-t)n$ members, including the head.

$w$ is the wage of the head; $R$ the full income; $p_2$ the price of good 2; the price of good 1 is fixed to 1; $C_1$ is the demand for good 1, $C_2$, the demand for good 2 and $l$ the demand for leisure; $\alpha$ is the coefficient of altruism (that lies between 0, no altruism, and 1, total altruism); once the guests have been supplied, the head keeps a share $\theta$ of the remaining amount of good 1 for himself, and shares the rest between the members of the nuclear family.

If $C_1$ is the total expenditure in good 1, the head allocates $tC_1$ to the guests, keeps $\theta(1-t)C_1$ for himself, and gives $(1-\theta)(1-t)C_1$ to his nuclear family, so that each member of the nuclear family, except the head, consumes $(1-\theta)(1-t)C_1/((1-t)n - 1)$.

## Household head's program

$$ \begin{array}{ll} \underset{\theta, C_1, C_2, l}{\operatorname{Max}} & u(\theta(1-t)C_1) + \varphi(C_2, l) + \alpha(n(1-t)-1)u\left(\frac{(1-\theta)(1-t)C_1}{n(1-t)-1}\right) \\ \text{subject to} & p_1C_1 + p_2C_2 + wl = R \end{array} $$

The head chooses $\theta$, $C_1$, $C_2$ and $l$ to maximize his utility. The solutions are given by the first order conditions. The head can escape redistribution if he only purchases good 2, although it is hard, as we said, to pretend that one does not eat. However, the cost is twofold, because the head wishes to consume some good 1, and his utility depends positively on the utility of the members of his nuclear family. Last, note that some goods of type 1 are partly
public goods; housing is one example. In this case, the head keeps $C_1$ for himself and for his nuclear family. Our model could be slightly extended by putting $(1 - \beta t)$ in the utility function instead of $(1 - t)$, where $\beta$ measures how private a good is ($0 \le \beta \le 1$), with $\beta = 0$ for a pure public good and $\beta = 1$ for a pure private good.

## Definition

By analogy with the Arrow-Pratt measure of relative risk aversion, we introduce the measure $r$ of the concavity of the utility function $r(x) = -\frac{xu''(x)}{u'(x)}$.

## Result

The demand for good 1 decreases when the proportion of guests increases, provided that relative risk aversion is decreasing and not above 1. In particular, power and logarithm functions verify this property. A sufficient condition is that the relative risk aversion decreases and that it is smaller than 1 in zero.<fnref n="26" />

## Proof

See Rapoport (2000b). This involves rather long comparative static calculations.<fnref n="27" />

<footnote n="26">²⁶ Notice that both conditions can not simultaneously hold if, at zero, $u'$ and $u''$ are null, but Inada conditions rule out this problem.</footnote>

<footnote n="27">²⁷ This result is probably true for a larger class of utility functions, but does not seem easy to obtain in a more general case. Particularly, the results have been established under the assumption of functional separability between good 1 and good 2 and leisure. Generalization would, of course, be welcome. The conditions are less strict if the coefficient of altruism is not too different from 1 or if it is null (Rapoport, 2000b).</footnote>
Intuitively, this result comes from the fact that the redistribution of good 1 increases the price of this good for the head, as if he were taxed. However, the problem is more complex, because the head can reduce what he allocates to the members of his nuclear family. Nevertheless, good 1 will be labeled as the "taxable good".

If the demand for good 1 decreases as $t$ increases, the demand either for good 2 or for leisure must increase. If good 2 and leisure are substitutes, the demand for one of them may decrease. The overall effect is ambiguous, depending on price- and income-effects.

## Applications

Food is a good candidate to test our model. After controlling for household size, expenditure on food at home in multi-guests households should be smaller than in households with fewer guests, and conversely for food away from home.<fnref n="28" /> Moreover, these two kinds of goods are good substitutes. Notice that if luxury goods are not divisible and are very expensive - a car is a good example - the head may only consume taxable goods and leisure. Then, he can only substitute leisure for good 1; in this case, we expect that the richer the head, the more of his income he can hide from the family taxation, especially if financial markets are imperfect. In archaic societies, where the range of goods was quite narrow, the substitution was often toward non taxable goods like leisure, sexual pleasure (polygamy) and children.

The problem with housing is more complex. Consumption of housing is hard to hide. We should then observe a reduction in the demand for housing as the proportion of guests in the household increases. However, on one hand, it is hard to adjust expenditures on housing, because it is hard to move each time a relative asks for hospitality, especially for the

<footnote n="28">²⁸ Food away from home is hard to observe, at least in not too small communities. But we use urban data.</footnote>
householders. Notice, however, that the mobility rate is very high in Gabon (20% a year in Libreville and Port-Gentil), a fact that can be explained by the model. One the other hand, the size of the household is not really exogenous, because outward signs of wealth incite relatives to join the household, and expenditures on housing are a perfectly observable signal. Therefore, a high demand for housing at t will induce an increase in household size and proportion of guests at t + 1, and then a decrease in the demand for housing, then a decrease of the size of household (in Libreville and Port-Gentil, the guests often go from one household to another<fnref n="29" />).

# V Is the structure of consumption modified by the presence of guests in the household?

## Introduction

We expect, according to our model of social pressure, that, if we acknowledge that the income is distributed by the head, he will buy less nonexcludable goods and more private goods if there are guests in the household or if he expects guests. We estimate a demand system to test this prediction.<fnref n="30" />

We estimate budget shares using the proportion of guests in the household as an independent variable. Here we are interested in how monthly income is spent. We then use net expenditures, that is expenditures including what is bought on credit less what is given (which is a separate budget heading). Moreover, since the amount of what is either received, taken from inventory by the shopkeepers or self-consumed might modify the budget shares, we introduced dummies describing these sources of goods (variables x*).<fnref n="31" />

<footnote n="29">²⁹ Perhaps they try to distribute the pressure among the members of the extended family.</footnote>

<footnote n="30">³⁰ We do not really estimate a system, as the independent variables are the same in every equation (see, for instance, Greene, 1997).</footnote>

<footnote n="31">³¹ The results do not vary very much if we use *per capita* amounts instead of dummies.</footnote>
To describe the composition of households, we introduce as an explanatory variable the proportion of guests in the household, as defined above. Afterwards, the results do not vary very much if the children and grandchildren of the spouse(s) of the head are classified as guests and not as members of the nuclear household.

In table 2 and 3, columns 3 and 4 display the results for the subsample of households with more than one member, as the proportion of guests does not make much sense if there is only one member (the head) in the household. We report the results in this case only for comparison purposes.

We estimate the following equations:

$$w_f = \alpha + \beta \ln \frac{x}{n} + \gamma \ln n + \delta \frac{n_a}{n} + \zeta \cdot \mathbf{v} + u$$

where $w_f$ is the budget share, $x$ total household expenditure, $n$ household size, $n_a$ the number of guests, and $\mathbf{v}$ is a vector of control variables.

As budget shares and *per capita* expenditure are constructed from expenditure, errors in $w_f$ and $\ln(x/n)$ are almost certainly correlated. We thus systematically use instrumental variable estimates of the above equations, using the logarithm of *per capita* cash income (and the set of explanatory variables) as the instrument for logarithm of *per capita* expenditure (as in Deaton and Paxson, 1998).

## Preliminary results

Rapoport (2000b) reproduces the regression estimates (OLS and IV) of Deaton and Paxson's specification. The results are in harmony with those obtained by these authors. The
coefficient (multiplied by 100) of the logarithm of household size in a total food share regression is in absolute value 3.39 for all households and 5.96 for households with more than one member. For all households the coefficient is between those computed by Deaton and Paxson for Taiwan and Thailand, exactly as the *per capita* income. For households with more than one member, the coefficient is much closer than Pakistan's and urban Thailand's. The same conclusions hold for food at home and food away from home. Last, the ratio of young children has no significant effect on food share, exactly as in Thailand, although there is an effect if one distinguishes food at home and food away from home (the comparable results are not reported by Deaton and Paxson). All these results are fully consistent with the conclusions of Deaton and Paxson, which, first, reinforces their results and, second, indicates that one can have confidence in our data.

### 3 Estimation of a demand system

Table 2 presents the results.

<table><thead><tr><th rowspan="2"></th><th colspan="2">ALL HOUSEHOLDS</th><th colspan="2">HOUSEHOLDS WITH MORE THAN ONE MEMBER</th></tr><tr><th>AT HOME</th><th>AWAY FROM HOME</th><th>AT HOME</th><th>AWAY FROM HOME</th></tr></thead><tbody><tr><td>ln of per capita expenditure</td><td>-0.160***<br>(-12.846)</td><td>-0.009*<br>(-1.825)</td><td>-0.184***<br>(-13.710)</td><td>-0.005<br>(-1.522)</td></tr><tr><td>ln of size of the household</td><td>-0.035***<br>(-2.621)</td><td>-0.023***<br>(-4.135)</td><td>-0.085***<br>(-5.233)</td><td>-0.009**<br>(-2.375)</td></tr><tr><td>1 if matrilineal ethnic group</td><td>-0.012<br>(-0.490)</td><td>-0.013<br>(-1.284)</td><td>0.006<br>(0.237)</td><td>-0.013**<br>(-2.219)</td></tr><tr><td>1 if patrilineal ethnic group</td><td>-0.008<br>(-0.307)</td><td>-0.022**<br>(-2.099)</td><td>0.005<br>(0.208)</td><td>-0.015**<br>(-2.569)</td></tr><tr><td>Fraction of adults in labor force</td><td>0.013<br>(0.387)</td><td>0.011<br>(0.786)</td><td>0.011<br>(0.331)</td><td>-0.001<br>(-0.159)</td></tr><tr><td>xfoodathome</td><td>0.012<br>(0.705)</td><td>-0.015**<br>(-2.174)</td><td>0.021<br>(1.231)</td><td>-0.004<br>(-0.934)</td></tr><tr><td>xfoodaway</td><td>-0.052***<br>(-2.810)</td><td>0.007<br>(0.976)</td><td>-0.023<br>(-1.223)</td><td>0.006<br>(1.426)</td></tr></tbody></table>
<table><caption>Table 2 : Food shares, with proportion of guests as right hand side variable</caption><tbody><tr><td>xbeverage</td><td>-0.023<br>(-1.295)</td><td>0.012*<br>(1.655)</td><td>-0.025<br>(-1.368)</td><td>0.003<br>(0.652)</td></tr><tr><td>xhousing</td><td>0.030<br>(1.291)</td><td>-0.002<br>(-0.214)</td><td>0.042<br>(1.526)</td><td>-0.008<br>(-1.224)</td></tr><tr><td>xclothes</td><td>0.007<br>(0.320)</td><td>0.008<br>(0.965)</td><td>0.010<br>(0.477)</td><td>-0.0004<br>(-0.089)</td></tr><tr><td>xdivers</td><td>-0.006<br>(-0.310)</td><td>0.002<br>(0.254)</td><td>-0.008<br>(-0.428)</td><td>-0.0005<br>(-0.111)</td></tr><tr><td>xtransport</td><td>-0.034<br>(-1.520)</td><td>0.003<br>(0.280)</td><td>-0.033<br>(-1.544)</td><td>0.003<br>(0.687)</td></tr><tr><td>xhealth</td><td>0.009<br>(0.274)</td><td>-0.010<br>(-0.737)</td><td>0.001<br>(0.049)</td><td>-0.002<br>(-0.221)</td></tr><tr><td>xschooling</td><td>0.043<br>(0.973)</td><td>0.010<br>(0.519)</td><td>0.054<br>(1.311)</td><td>0.007<br>(0.703)</td></tr><tr><td>1 if the head is selfemployed</td><td>-0.021<br>(-0.624)</td><td>0.021<br>(1.527)</td><td>-0.011<br>(-0.323)</td><td>0.016**<br>(2.141)</td></tr><tr><td>1 if the head is in private sector</td><td>0.003<br>(0.099)</td><td>0.003<br>(0.264)</td><td>0.008<br>(0.298)</td><td>-0.001<br>(-0.095)</td></tr><tr><td>1 if the head is in public sector</td><td>-0.022<br>(-0.742)</td><td>0.003<br>(0.207)</td><td>-0.013<br>(-0.489)</td><td>-0.001<br>(-0.125)</td></tr><tr><td>1 if the head is in parapublic sector</td><td>-0.027<br>(-0.776)</td><td>0.001<br>(0.081)</td><td>-0.011<br>(-0.348)</td><td>-0.002<br>(-0.263)</td></tr><tr><td>1 if tenant</td><td>-0.022<br>(-1.250)</td><td>-0.004<br>(-0.501)</td><td>-0.037**<br>(-2.183)</td><td>0.005<br>(1.301)</td></tr><tr><td><strong>fraction of guests</strong></td><td><strong>-0.066*<br>(-1.823)</strong></td><td><strong>0.036**<br>(2.368)</strong></td><td><strong>-0.080**<br>(-2.418)</strong></td><td><strong>0.041***<br>(5.360)</strong></td></tr><tr><td>1 if surveyed in oct-nov</td><td>0.036**<br>(2.411)</td><td>-0.008<br>(-1.287)</td><td>0.002<br>(0.133)</td><td>0.002<br>(0.457)</td></tr><tr><td>1 if lives in Port-Gentil</td><td>-0.019<br>(-0.942)</td><td>-0.015*<br>(-1.857)</td><td>-0.025<br>(-1.263)</td><td>-0.005<br>(-1.021)</td></tr><tr><td>Intercept</td><td>2.222***<br>(15.587)</td><td>0.165***<br>(2.816)</td><td>2.567***<br>(16.728)</td><td>0.082**<br>(2.326)</td></tr><tr><td>Adjusted R²</td><td>0.413</td><td>0.174</td><td>0.461</td><td>0.176</td></tr><tr><td>Nb of observations</td><td>412</td><td>412</td><td>358</td><td>358</td></tr></tbody></table>

*** significant at the 1%-level; ** at the 5%-level; * at the 10%-level. t-statistics are in parentheses.

Only relatively few variables are significant. The food at home share decreases when the total expenditures increase, and the food away from home likewise, although the effect is much smaller and insignificant at 5% (both goods are necessities). Computed at the average,
the consumption-elasticities *per capita* are 0.56 and 0.67 respectively for food at home and food away from home. There are no significant differences between Gabonese and non Gabonese for food at home; however, Gabonese spend proportionally less than migrants on food away from home. This is not surprising as non-Gabonese men often live alone in Gabon. Notice that there is no difference between matrilineal and patrilineal ethnic groups. Dummies controlling for external resources (x* variables), mainly gifts and taking from inventory, are seldom significant. For all households, receiving food for home consumption or taking food from inventory reduces the food away from home share, and conversely, being invited to eat out reduces the food at home share; the signs are the same if we keep only households with more than one member, although the coefficients are no longer significant. Thus only crossed effects are significant and only for the whole sample. This result is not easy to interpret, but these effects disappear when we drop households with only one member. These members are mainly men (72%); the effects could be labeled as "single man effects". As the food at home share (respectively away from home share) of singles<fnref n="32" /> is smaller (respectively higher) than the share of other households, external resources of food for home consumption likely play only a minor role on food expenditures of singles, because they cannot be cut down (breakfast, for example) and only incite the individual to eat out less frequently. By symmetry, it is not because one have been invited by exception that one will eat out less frequently; one will

<footnote n="32">³² Particularly if the single is a man. The average food away from home share of all singles is 7.2%; it is 9.6% for male singles, and only 1.7% for households with more than one member. Concerning food at home, the average shares are 33.6% for all singles, 31.5% for male singles and 36.7% for households with more than one member.</footnote>
simply not prepare any meal the invitation day.<fnref n="33" /> Notice lastly that dummies describing the activity of the head have no significant impact.

The estimated coefficient on the guest variable has the expected sign in all specifications: negative for the food at home share (significant at 6.9% if we keep all households and at 1.6% for households with more than one adult) and positive (1.8% and 0.1% respectively) for the food away from home share. The coefficients are quite large, between -0.066 and -0.080 for the food at home, and between +0.036 and +0.041 for the food away from home (see table 3 below). If we use the whole expenditure, including housing expenditure, autoconsumption, taking from inventory and receipts of gifts (as in Deaton and Paxson, 1998) the signs do not vary, but the coefficient becomes insignificant for food at home.

Nevertheless, the results might differ with the sex and the age of the members of the household. For example, young women could be welcomed if they help to prepare meals or to keep an eye on children.

## Household structure and the structure of consumption

Here we describe more fully household composition. We classify household members according to their sex, age (4 classes: 0-5 years old, 6-16 years old, 17-55 years old and 56 or above) and whether they belong to the nuclear household or not. Men and women above 55 are grouped together. We then have 14 groups.

We estimate the following equations:

$$w_f = \alpha + \beta \ln \frac{x}{n} + \gamma \ln n + \sum_{k=1}^{K'} \eta_k \frac{n_k}{n} + \zeta \cdot \mathbf{v} + u$$

<footnote n="33">³³ If we use logarithms of amounts instead of dummies, there are almost no differences on key-variables here and in the following sections.</footnote>
where $w_f$ is the budget share, $x$ whole expenditure, $n$ household size, $n_k$ the number of members in group $k$, the groups being defined by sex, age and the link with the head. $v$ is a vector of control variables.

<table><caption>Table 3: Effects of substitution, at given size, of a member of the extended family for a member of the nuclear family of the same sex- and same age-group, in percentage points, computed at average household size</caption><thead><tr><th>GROUPS<br>SEX AND AGE</th><th>SAMPLE</th><th>FOOD AT<br>HOME</th><th>FOOD AWAY<br>FROM HOME</th><th>BEVERAGES<br>AND TOBACCO</th><th>HOUSING AND<br>ENERGY</th><th>CLOTHING<br>AND JEWELRY</th></tr></thead><tbody><tr><td rowspan="2">All groups</td><td>All</td><td>-1.21*</td><td>0.65**</td><td>0.48**</td><td>-0.61</td><td>0.20</td></tr><tr><td>Size >1</td><td>-1.24**</td><td>0.63***</td><td>0.43**</td><td>-0.47</td><td>0.20</td></tr><tr><td rowspan="2">Men 17-55</td><td>All</td><td>-3.53***</td><td>0.29</td><td>-0.18</td><td>1.73</td><td>-0.09</td></tr><tr><td>Size >1</td><td>-4.59***</td><td>0.72**</td><td>-0.67</td><td>3.44***</td><td>-0.06</td></tr><tr><td rowspan="2">Women 17-55</td><td>All</td><td>0.93</td><td>0.83</td><td>0.13</td><td>-0.28</td><td>-1.86**</td></tr><tr><td>Size >1</td><td>0.74</td><td>0.80***</td><td>0.52</td><td>-1.44</td><td>-1.30*</td></tr><tr><td rowspan="2">Boys 0-5</td><td>All</td><td>-1.69</td><td>-0.06</td><td>0.59</td><td>-2.45</td><td>4.54***</td></tr><tr><td>Size >1</td><td>-0.77</td><td>-0.17</td><td>0.20</td><td>-2.63</td><td>3.74***</td></tr><tr><td rowspan="2">Girls 0-5</td><td>All</td><td>-6.94*</td><td>-0.21</td><td>-0.93</td><td>1.63</td><td>0.30</td></tr><tr><td>Size >1</td><td>-4.42</td><td>-0.67</td><td>-0.82</td><td>1.51</td><td>-0.02</td></tr><tr><td rowspan="2">Boys 6-16</td><td>All</td><td>1.89</td><td>0.67</td><td>-0.56</td><td>1.94</td><td>-1.07</td></tr><tr><td>Size >1</td><td>0.19</td><td>0.68</td><td>-0.43</td><td>2.17</td><td>-1.10</td></tr><tr><td rowspan="2">Girls 6-16</td><td>All</td><td>-0.54</td><td>0.40</td><td>2.09***</td><td>-2.80</td><td>1.42</td></tr><tr><td>Size >1</td><td>0.31</td><td>0.004</td><td>1.71***</td><td>-1.67</td><td>1.07</td></tr><tr><td rowspan="2">Above 56</td><td>All</td><td>-1.50</td><td>0.96</td><td>-0.22</td><td>2.20</td><td>1.23</td></tr><tr><td>Size >1</td><td>-1.85</td><td>0.88</td><td>-0.41</td><td>1.04</td><td>1.56</td></tr><tr><td rowspan="2">Average share</td><td>All</td><td>36.12</td><td>2.73</td><td>4.63</td><td>15.61</td><td>7.53</td></tr><tr><td>Size >1</td><td>36.68</td><td>1.73</td><td>4.63</td><td>15.06</td><td>7.90</td></tr></tbody></table>

In table 3, we summarize the effects of substitution, at given size, of a member of the extended family for a member of the nuclear family of the same sex and same age-group. We thus run each regression with a different reference in order to measure directly the effect. So for 6-16 years-old girls, the regression was run with all the variables of composition, except the proportion of the 6-16 years-old girls of the nuclear family.<fnref n="34" />

<footnote n="34">³⁴ We also use the same control variables as in table 1.</footnote>
For example: the average food share of households with more than one member is 36.68% (last row). If in one of these households with average size (6.49), we substitute a 30-years old (between 17 and 55) man of the extended family for a man of the nuclear family of the same age-group, the food at home share decreases by 4.59 percent points (significant at 1%).

Thus, at given household size, the food at home share decreases with the number of guests. The effect is very strong for 17-55-years-old men and otherwise not significant. It is positive for the 17-55-years-old women, although non significant. Conversely, the food away from home share increases with the number of guests. The effect is significant only for adults younger than 55 and only in the subsample. However, even if insignificant, the effect is always positive, except for babies.

The higher the fraction of guests, the higher the beverage and tobacco share. But the effect seems to come exclusively from 6-16-years-old girls. The shares of housing and energy and of clothes and jewelry are unchanged by the substitution of a member of the extended family for a member of the nuclear family. But in the subsample, the substitution of a 17-55-years-old man has a strong positive effect on the housing share. Moreover, the substitution of a 17-55-years-old woman has a negative effect on the clothing share and the substitution of a young boy a very significant positive effect.

## Discussion

Notice first that almost no guests are in the labor market. More generally, as explained above, there is only one member who works in the household: the head and sometimes his or her spouse. It is thus not necessary here to take labor supply into account, as would be the case in a rural region.
The results with respect to food are exactly as expected from the model of social pressure. The fraction of guests does not modify the total food share,<fnref n="35" /> but does change its composition: the food at home share decreases and the food away from home increases when, at a given household size, the number of guests increases. This can be interpreted as an indication that the head cuts expenditure on observable food consumption at the expense of food whose consumption is harder to observe. These effects only concern adults: men for both kinds of food and women for food at home. This is not surprising, as the power of children is most likely weaker than the power of adults. Of course it is not the child who exerts the pressure, but probably her parents, but it is the child who has to observe the consumption. It is not clear if she is able to know and to inform her parents that her host did not respect the norm. Therefore, it is not necessary to hide incomes and consumption from children. There is then only the negative income-effect from the obligation of hospitality. Moreover, it is common that households containing young guests confide the care of their young children to others.<fnref n="36" /> Hence perhaps young nephews and nieces are treated by the head like his own children, that is what the Gabonese say anyway. But we show here that the situation is different for adult guests. Notice that our results show that members of the nuclear household are less well-fed in households with guests than in others.<fnref n="37" />

Results for beverages and tobacco are also compatible with the model, especially because what is drunk at bars is not easily observed. But the effect comes from the 6-16-years-

<footnote n="35">³⁵ Results are not shown. If we estimate the food share, the fraction of guests has a negative but insignificant effect (-0,031, *t* = -0,891 for the whole sample and -0,039, *t* = -1,188 for households with more than one member).</footnote>

<footnote n="36">³⁶ Unfortunately this can not be observed in the 1994 data.</footnote>

<footnote n="37">³⁷ For example, Pitt *et alii* (1990), study the relationships between nutrition, labor-market productivity and health heterogeneity.</footnote>
old girls, which is not easy to explain. Remember that this budget heading is not limited to alcoholic drinks. The distinction between alcoholic and non-alcoholic beverages does not help to solve the puzzle: the effect concerns only alcoholic beverages and tobacco and not sweet drinks,<fnref n="38" /> so that one can not argue, as someone suggested to us, that young girls receive some payments in this form for help in domestic tasks. It could be interesting to discriminate between drinks at bars and drinks at home, as the place of purchase appears in the data. The problem is that, in Gabon, it is possible, and not uncommon, to buy a drink in a bar and drink it at home.

The effect on housing is also of interest. There is no noticeable effect if we use the fraction of guests; but if the members are differentiated by sex and age and if we only keep the households with more than one member, we can see that the fraction of 17-55-years-old men has a very positive impact. As housing is a good whose consumption is very easy to observe for a member of the household, the housing share should decrease with the fraction of guests. But it is observable by people who do not belong to the household too. The quality of housing thus signals high income, so that members of kinship who do not live in the household may be attracted, and the household will more probably have guests. The fraction of guests is then certainly endogenous.<fnref n="39" /> Lastly, as mentioned above, choice of house is a long run matter, so housing expenditure is difficult to change in the short run.

The effect on the clothing share of the substitution of a woman of the extended family for a woman of the nuclear family is in harmony with the model of social pressure, because this consumption is generally individual. But, as relatives can see the clothes one wears, it is

<footnote n="38">³⁸ Results not shown.</footnote>

<footnote n="39">³⁹ A test is however not easy, as the number of guests is better estimated by a discrete model (negative binomial or ordered probit) than by a linear regression (see Rapoport, 2000c).</footnote>
hard to hide this expenditure. We then expect a weaker effect.<fnref n="40" /> Furthermore, it is possible
that little boys are those who consume the least clothes, because they are not interested in
clothes and jewelry. However it seems hard to hide jewelry from a little girl. Anyway, the
effect of the substitution of little boys is rather strong, so it is not clear if this explanation is
convincing.

Why do the effects depend so much on an individual's sex? Except for food away from
home, the effects are always opposite if we consider 17-55-years old members. The survey
does not include this information, but it is clear that female guests help in a number of
domestic tasks (shopping, preparation of meals, child minding, etc.), so that it is hard to
reduce food expenditure. They even help in work activities when, for example, the head or his
spouse sells at the market. They could simply be paid for all this help. However, the effect
predicted by the model does not disappear. It can be detected in the food away from home and
clothing shares. But we must not forget that the women are seldom completely inactive.
Lastly, the power of women in the extended family is certainly lower than the power of men.

Some of the results could be explained by a model of altruism. But we should assume
that the coefficient of altruism depends firstly on the biological proximity with the head, and
second on the sex and the age of the members of the extended family. The model of exchange
of services for transfers of Cox (1987) can not explain why there are some male guests who
never help the head; moreover, it is hard to believe that the head needs the attention of his
adult nephews. We could combine exchange and altruism as suggested by Cox, but it would

<footnote n="40">⁴⁰ The mechanism could be more subtle. One of the surveyor with whom I have worked at Port-Gentil bought shoes that were too small for him. He suffered a bit, but explained to me, as I did not understand why he chose them, that his little brother took the same size as him. It was the only way he found to keep his shoes...</footnote>
be necessary to suppose again that the coefficient of altruism depends on the sex and the age
of the recipient, that is, for example, that transfers are motivated mainly by altruism if the
recipient is a man and by the exchange motive if she is a woman.

VI Conclusion

We have then shown that the composition of the household matters when we try to describe the structure of consumption. Beyond the composition by sex and age, family ties matter too. This result is above all striking if we consider the 17-55 years old members. We interpret this as evidence that hospitality is decided under the pressure of relatives. Thus we have first addressed the question of the distribution of goods, especially of food, within the household, and, second, tried to show what the relations within the extended family in Gabon are. The differences between men and women suggest however that a more complete model with domestic production should probably be useful to understand more fully the pattern of expenditures in African households.

The conclusions are, in the main, in harmony with our model of social pressure, yet the
data we used suffer from two important disadvantages. First, there are only 412 family-units
in the sample; second, our results would be more significant if with panel data we could
control for unobserved heterogeneity and measure the transformation of the structure of
consumption when household composition is modified.

Consumption structure is not the only prediction of our model of social pressure. As
we pointed out, substitution of leisure for observable goods should be investigated. *Ceteris paribus*, labor supply of the head should be weaker in households with guests. Moreover,
fertility and polygamy will be more prominent when the range of goods is narrow. In the same
spirit, if anonymity does not exist, investments and saving will not be encouraged as
observable resources will be taxed. In certain cases, this can explain why "archaic" societies
preferred lack of privacy, as, in this way, the group can easily observe income and
consumption of its members. Even investments in human capital will be deterred if they signal
a high level of income. Rapoport (2000c) shows that only income that can be observed by the
relatives has an impact on the number of guests.

Of course, most part of these predictions have yet to be tested. Some of them such as
investments, labor supply or fertility, have direct consequences on economic development. In
terms of the current paper, our results show that members of the nuclear household are less
well-fed in households with guests than in others.
# Appendix

<table><caption>Table A: Descriptive Statistics</caption><thead><tr><th rowspan="2"></th><th colspan="3">ALL HOUSEHOLDS</th><th colspan="3">HOUSEHOLDS WITH MORE THAN 1 MB</th></tr><tr><th>MEAN</th><th>SD<br>ERROR</th><th>MIN</th><th>MAX</th><th>MEAN</th><th>SD<br>ERROR</th><th>MIN</th><th>MAX</th></tr></thead><tbody><tr><td>Food at home share</td><td>0.361</td><td>0.188</td><td>0.023</td><td>1</td><td>0.367</td><td>0.182</td><td>0.023</td><td>0.951</td></tr><tr><td>Food away from home share</td><td>0.027</td><td>0.065</td><td>0</td><td>0.639</td><td>0.017</td><td>0.034</td><td>0</td><td>0.458</td></tr><tr><td>Beverage and Tobacco share</td><td>0.046</td><td>0.054</td><td>0</td><td>0.375</td><td>0.046</td><td>0.049</td><td>0</td><td>0.319</td></tr><tr><td>Housing and Energy share</td><td>0.156</td><td>0.145</td><td>0</td><td>0.851</td><td>0.151</td><td>0.139</td><td>0</td><td>0.851</td></tr><tr><td>Clothing and Jewels share</td><td>0.075</td><td>0.077</td><td>0</td><td>0.413</td><td>0.079</td><td>0.078</td><td>0</td><td>0.413</td></tr><tr><td>Size of household</td><td>5.485</td><td>4.409</td><td>1</td><td>32</td><td>6.485</td><td>4.276</td><td>2</td><td>32</td></tr><tr><td>1 if matrilineal ethnic group</td><td>0.371</td><td>0.484</td><td>0</td><td>1</td><td>0.420</td><td>0.494</td><td>0</td><td>1</td></tr><tr><td>1 if patrilineal ethnic group</td><td>0.344</td><td>0.476</td><td>0</td><td>1</td><td>0.376</td><td>0.485</td><td>0</td><td>1</td></tr><tr><td>Fraction of adults in labor force</td><td>0.503</td><td>0.352</td><td>0</td><td>1</td><td>0.453</td><td>0.305</td><td>0</td><td>1</td></tr><tr><td>xfoodathome (see text)</td><td>0.679</td><td>0.468</td><td>0</td><td>1</td><td>0.670</td><td>0.471</td><td>0</td><td>1</td></tr><tr><td>xfoodaway (see text)</td><td>0.359</td><td>0.480</td><td>0</td><td>1</td><td>0.322</td><td>0.468</td><td>0</td><td>1</td></tr><tr><td>xbeverage (see text)</td><td>0.576</td><td>0.495</td><td>0</td><td>1</td><td>0.594</td><td>0.492</td><td>0</td><td>1</td></tr><tr><td>xhousing (see text)</td><td>0.122</td><td>0.327</td><td>0</td><td>1</td><td>0.079</td><td>0.270</td><td>0</td><td>1</td></tr><tr><td>xclothes (see text)</td><td>0.201</td><td>0.401</td><td>0</td><td>1</td><td>0.189</td><td>0.392</td><td>0</td><td>1</td></tr><tr><td>xdivers (see text)</td><td>0.207</td><td>0.405</td><td>0</td><td>1</td><td>0.214</td><td>0.411</td><td>0</td><td>1</td></tr><tr><td>xtransport (see text)</td><td>0.164</td><td>0.371</td><td>0</td><td>1</td><td>0.189</td><td>0.392</td><td>0</td><td>1</td></tr><tr><td>xhealth (see text)</td><td>0.073</td><td>0.260</td><td>0</td><td>1</td><td>0.084</td><td>0.278</td><td>0</td><td>1</td></tr><tr><td>xschooling (see text)</td><td>0.031</td><td>0.174</td><td>0</td><td>1</td><td>0.038</td><td>0.191</td><td>0</td><td>1</td></tr><tr><td>1 if the head is self-employed</td><td>0.222</td><td>0.416</td><td>0</td><td>1</td><td>0.164</td><td>0.371</td><td>0</td><td>1</td></tr><tr><td>1 if the head is in private sector</td><td>0.269</td><td>0.444</td><td>0</td><td>1</td><td>0.283</td><td>0.451</td><td>0</td><td>1</td></tr><tr><td>1 if the head is in public sector</td><td>0.204</td><td>0.403</td><td>0</td><td>1</td><td>0.247</td><td>0.432</td><td>0</td><td>1</td></tr><tr><td>1 if the head is in parapublic sector</td><td>0.089</td><td>0.286</td><td>0</td><td>1</td><td>0.103</td><td>0.305</td><td>0</td><td>1</td></tr><tr><td>ln of per capita expenditure</td><td>11.091</td><td>0.848</td><td>6.903</td><td>14.400</td><td>11.002</td><td>0.786</td><td>8.570</td><td>14.400</td></tr><tr><td>ln of per capita cash income/100000</td><td>-0.518</td><td>0.884</td><td>-4.06</td><td>2.495</td><td>-0.626</td><td>0.827</td><td>-3.306</td><td>2.495</td></tr><tr><td>1 if tenant</td><td>0.500</td><td>0.501</td><td>0</td><td>1</td><td>0.443</td><td>0.497</td><td>0</td><td>1</td></tr><tr><td>1 if surveyed in october-november</td><td>0.559</td><td>0.497</td><td>0</td><td>1</td><td>0.552</td><td>0.498</td><td>0</td><td>1</td></tr><tr><td>1 if lives in Port-Gentil</td><td>0.164</td><td>0.370</td><td>0</td><td>1</td><td>0.169</td><td>0.376</td><td>0</td><td>1</td></tr><tr><td>fraction of guests</td><td>0.16</td><td>0.218</td><td>0</td><td>0.900</td><td>0.196</td><td>0.226</td><td>0</td><td>0.900</td></tr><tr><td>fraction of boys (0-5 ys old) guest</td><td>0.011</td><td>0.046</td><td>0</td><td>0.333</td><td>0.014</td><td>0.051</td><td>0</td><td>0.333</td></tr><tr><td>fraction of girls (0-5 ys old) guest</td><td>0.009</td><td>0.037</td><td>0</td><td>0.333</td><td>0.011</td><td>0.040</td><td>0</td><td>0.333</td></tr><tr><td>fraction of boys (6-16 ys old) guest</td><td>0.015</td><td>0.055</td><td>0</td><td>0.500</td><td>0.019</td><td>0.060</td><td>0</td><td>0.500</td></tr><tr><td>fraction of girls (6-16 ys old) guest</td><td>0.023</td><td>0.068</td><td>0</td><td>0.500</td><td>0.028</td><td>0.074</td><td>0</td><td>0.500</td></tr><tr><td>fraction of men (17-55 ys old) guest</td><td>0.057</td><td>0.121</td><td>0</td><td>0.667</td><td>0.070</td><td>0.130</td><td>0</td><td>0.667</td></tr><tr><td>fraction of wom. (17-55 ys old) guest</td><td>0.036</td><td>0.093</td><td>0</td><td>0.500</td><td>0.045</td><td>0.101</td><td>0</td><td>0.500</td></tr><tr><td>fraction of olds (&gt; 55 ys old) guest</td><td>0.008</td><td>0.039</td><td>0</td><td>0.500</td><td>0.01</td><td>0.043</td><td>0</td><td>0.500</td></tr><tr><td>fraction of boys (0-5 ys old) nuclear</td><td>0.068</td><td>0.112</td><td>0</td><td>0.500</td><td>0.084</td><td>0.118</td><td>0</td><td>0.500</td></tr><tr><td>fraction of girls (0-5 ys old) nuclear</td><td>0.07</td><td>0.118</td><td>0</td><td>0.571</td><td>0.085</td><td>0.125</td><td>0</td><td>0.571</td></tr><tr><td>fraction of boys (6-16 ys old) nuclear</td><td>0.08</td><td>0.121</td><td>0</td><td>0.625</td><td>0.098</td><td>0.127</td><td>0</td><td>0.625</td></tr><tr><td>fraction of girls (6-16 ys old) nuclear</td><td>0.088</td><td>0.131</td><td>0</td><td>0.667</td><td>0.108</td><td>0.138</td><td>0</td><td>0.667</td></tr><tr><td>fraction of men (17-55 ys old) nucle</td><td>0.262</td><td>0.303</td><td>0</td><td>1</td><td>0.180</td><td>0.150</td><td>0</td><td>0.667</td></tr><tr><td>fraction of wom. (17-55 ys old) nucle</td><td>0.221</td><td>0.219</td><td>0</td><td>1</td><td>0.224</td><td>0.150</td><td>0</td><td>1</td></tr><tr><td>fraction of olds (&gt; 55 ys old) nuclear</td><td>0.051</td><td>0.199</td><td>0</td><td>1</td><td>0.026</td><td>0.120</td><td>0</td><td>1</td></tr></tbody></table>
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