In a recent article in the Water Resources Bulletin, Hansen and Narayanan (H-N) estimated several monthly time series models of municipal water demand for Salt Lake City, Utah. One model was then used to conduct an ex post analysis of water demand between 1975 and 1977 (Hansen and Narayanan, 1981. While H-N are to be commended for attempting to further knowledge in this area, several theoretical, econometric, and analysis problems exist in their study which we believe limits the usefulness of the material presented.
MODEL FORMULATIONSeveral problems exist in the model formulation section. Problems are encountered from either misspecification of equations, careless editing or presentation, or inadequate development of a theoretical model. For example, D1 a nongrowing season dummy, is reported to have a value of zero during the growing season and one during the nongrowing season; but in the matrix and equation presentations, the reverse appears to be the case. In H-N's twin nongrowing season equations, D1 was omitted from the nongrowing season equation. Yet in the matrix presentation, the coefficient of D1 a p pears as (8; -$). Although 8: has not been identified, we assume it is the intercept of the growing season equation since both quantity demanded and the error term are asterisked. If this is the case, this implies that D1 has a value of one during the growing season and zero during the nongrowing months. Although this error may appear minor, it is unclear to us if H-N truly understand the equation and matrix manipulation they are attempting to explain. In addition, individuals with little knowledge of econometrics would find this section difficult to understand.The process H-N appear to use to estimate the appropriate demand model implies that little attention is paid to theoretical development. They appear to have estimated two OLS equations (H-N, Figure 2), eliminated nonsignificant variables, reestimated, then experimented with different seasonal variables.Using this ad hoc framework with the same data would tend to yield a model with significant explanatory variables and a high R2 value; however, what they have is a model developed to fit the data rather than determining if economic theory explains water demand.
The appearance of major studies by Karl Deutsch and Ernst Haas in the late 1950's won for integration theory a prominent position among the contemporary approaches to the study of international relations. A decade later its achievements are very much a matter of debate. While many students of integration theory have been led, by disappointment with results, to focus their attention on smaller and more manageable units, such as local communities and city-suburb relations, others continue investigations at the international level.
Rome is noted for its water and waste water systems which were constructed during ancient times. This paper is a discussion of the impact these systems had on living conditions in the imperial city. Rome's water system provided a constant supply to centrally located areas in contrast to modern systems which deliver water on demand to individual connections. For both water and waste water systems, access points were generally outside the household. Because of this lack of individual connections, Romans were forced to spend much of their time outside their tenements in the baths, latrines, arenas, streets, and shops of the imperial city.
Este estudo apresenta resultados de uma pesquisa desenvolvida durante seis meses em duas academias de ginástica e musculação localizadas em Florianópolis. As investigações – norteadas pelo fenômeno contemporâneo do culto do corpo – mostram que a corrida ascética pela forma física idealizada envolve a louvação/desprezo de certas regiões corporais, além de fronteiras simbólicas e materiais que influenciam homens e mulheres na escolha de diferentes práticas. Assim, liga-se ao gênero a geografia destes espaços e as diferenças nas hierarquias pautadas na imagem corporal. Os resultados apontam para a fluidez das relações humanas e fazem pensar em um possível eclipse do sujeito.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.