Unitary Model (unitary + model)

Distribution by Scientific Domains


Selected Abstracts


Estrogen and Bone,a Reproductive and Locomotive Perspective,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2003
Teppo Ln Järvinen MD
Abstract The primary function of the skeleton is locomotion, and the primary function of estrogen is reproduction. When the skeleton is considered within this locomotive context, the onset of estrogen secretion at puberty leads to packing of mechanically excess mineral into female bones for reproductive needs. Accordingly, the unpacking of this reproductive safety deposit at menopause denotes the origin of type I osteoporosis. Introduction: According to the prevailing unitary model of involutional osteoporosis, female postmenopausal bone loss can be described as having an initial accelerated, transient phase (type I), followed by a gradual continuous phase (type II). Estrogen withdrawal is generally accepted as the primary cause of the type I osteoporosis. Thus, the quest to uncover the origin of type I osteoporosis has focused on the estrogen withdrawal-related skeletal changes at and around the menopause. However, considering that the cyclical secretion of estrogen normally begins in early adolescence and continues over the entire fertile period, one could argue that focusing on perimenopause alone may be too narrow. Materials and Methods: This is not a systematic review of the literature on the skeletal function of estrogen(s), but rather, an introduction of a novel structure- and locomotion-oriented perspective to this particular issue through pertinent experimental and clinical studies. Results and Conclusions: When considering locomotion as the primary function of the skeleton and integrating the classic findings of the pubertal effects of estrogen on female bones and the more recent hypothesis-driven experimental and clinical studies on estrogen and mechanical loading on bone within this context, a novel evolution-based explanation for the role of estrogen in controlling female bone mass can be outlined: the onset of estrogen secretion at puberty induces packing of mechanically excess bone into female skeleton for needs of reproduction (pregnancy and lactation). Accordingly, the unpacking of this reproductive safety deposit of calcium at menopause denotes the accelerated phase of bone loss and thus the origin of type I osteoporosis. [source]


Resources at Marriage and Intrahousehold Allocation: Evidence from Bangladesh, Ethiopia, Indonesia, and South Africa*

OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 3 2003
Agnes R. Quisumbing
We test the unitary versus collective model of the household using specially designed data from Bangladesh, Ethiopia, Indonesia, and South Africa. Human capital and individual assets at the time of marriage are used as proxy measures for bargaining power. In all four countries, we reject the unitary model as a description of household behaviour, but fail to reject the hypothesis that households are Pareto-efficient. In Bangladesh and South Africa, women's assets increase expenditure shares on education, while in Ethiopia it is men's assets that have this effect. These increases have different implications for boys and girls across countries, however. [source]


GENDER DISCRIMINATION, INTRAHOUSEHOLD RESOURCE ALLOCATION, AND IMPORTANCE OF SPOUSES' FATHERS: EVIDENCE ON HOUSEHOLD EXPENDITURE FROM RURAL INDIA

THE DEVELOPING ECONOMIES, Issue 4 2006
Nobuhiko FUWA
D12; D13; D63; D64 Data collected from rural India was used to examine the rules governing intrahousehold resource allocations. Testing for gender-age discrimination among household members using Deaton's (1989) method, results suggest a general bias favoring boys over girls in allocation of consumption goods, however, the findings are not always statistically significant. Intrahousehold resource allocation rules are then examined to see if such discrimination is based on the unanimous decision of parents. The novelty in our test on allocation rule are: (1) use of grandparental variables as extra-household environmental parameters (EEPs) in expenditure estimation, (2) derivation of a test of the unitary model that only requires EEPs, and (3) semi-formal use of survival status of grandparents in testing collective models. It is interesting that spouse's father characteristics are importantly correlated with greater mother and child goods expenditure shares, and smaller father goods shares. Their survival status matters, and this is stronger evidence for a collective as opposed to unitary model. [source]


Intra-Household Resource Allocation, Consumer Preferences and Commodity Tax Reforms: Australian Evidence

THE ECONOMIC RECORD, Issue 247 2003
Paul Blacklow
Empirical analysis of household expenditure behaviour has traditionally ignored the issue of resource allocation between household members, assuming that they have identical or unitary preferences. This paper relaxes that assumption, develops a household sharing rule and proposes intra-household demand systems that are able to identify differences in the preferences of members from conventional data. The resulting price and expenditure elasticities are used to demonstrate that collective demand models suggest different directions for commodity tax reforms to those implied by the traditional unitary model. [source]