Oil and gas depletion: Diffusion models and forecasting under strategic intervention

Crude oil and natural gas depletion may be modelled by a diffusion process based upon a constrained life-cycle. Here we consider the Generalized Bass Model. The choice is motivated by the realistic assumption that there is a self-evident link between oil and gas extraction and the spreading of the modern technologies in wide areas such as transport, heating, cooling, chemistry and hydrocarbon fuels consumption. Such a model may include deterministic or semi-deterministic regulatory interventions. Statistical analysis is based upon nonlinear methodologies and more flexible autoregressive structure of residuals. The technical aim of this paper is to outline the meaningful hierarchy existing among the components of such diffusion models. Statistical effort in residual component analysis may be read as a significant confirmation of a well-founded diffusion process under rare but strong deterministic shocks. Applications of such ideas are proposed with reference to world oil and gas production data and to particular regions such as mainland U.S.A., U.K., Norway and Alaska. The main results give new evidence in time-peaks location and in residual times to depletion.     

Population Dynamics in Italy in the Middle Ages: New Insights from Archaeological Findings

Studies of settlements in Italy indicate that during the Early Middle Ages (6th–9th centuries) the Italian population was stagnant, whereas a slow but persistent growth followed during the High Middle Ages (10th–13th). However, the components of the dynamics of the Italian population in the long period between the Justinian Plague (around 565 in Italy) and the Black Death (1348) are largely unknown. In this article, data from anthropometric analysis of the skeletons in 154 Italian cemeteries that date between the 1st century BCE and the 13th century are used to gain new insights on mortality of adults and nutrition. Adult mortality was higher during the Early Middle Ages than during the Roman Empire and the High Middle Ages, suggesting that the stagnation of population was determined by higher mortality. During the Early Middle Ages, however, nutritional levels were higher, as suggested by taller statures, more widespread meat consumption, and longer periods of breastfeeding. We discuss some possible research lines to resolve this apparent contradiction.     

Framing of information on the use of public finances, regulatory fit of recipients and tax compliance

Information campaigns to increase tax compliance could be framed in different ways. They can either highlight the potential gains when tax compliance is high, or the potential losses when compliance is low. According to regulatory focus theory, such framing should be most effective when it is congruent with the promotion or prevention focus of its recipients. Two studies confirmed the hypothesized interaction effects between recipients’ regulatory focus and framing of information campaigns, with tax compliance being highest under conditions of regulatory fit. To address taxpayers effectively, information campaigns by tax authorities should consider the positive and negative framing of information, and the moderating effect of recipients’ regulatory focus.     

Women and poverty: insights from individual consumption in Albania

This paper studies how a society with traditional gender norms and competitive marriage market conditions may favor unequal distribution of resources within households and a consequent increase in female poverty. We propose a method to estimate individual consumption from household expenditure data. After estimating individual consumption, we apply a fuzzy approach for poverty analysis. Compared to standard poverty measures, the approach is less sensitive to changes in the distribution of consumption around the poverty line, generated when accounting for unequal distribution of household resources. The approach, applied to the analysis of individual poverty in Albania, revealed considerable intrahousehold inequality that specifically affects women and is correlated with imbalances in the sex ratio induced by past migrations. This leads to an expected general increase in poverty rates, mainly driven by a previously unperceived issue, female poverty, which emerges as an aspect of concern to consider in future anti-poverty policies.     

Cohort Replacement and Homeostasis in World Population, 1950–2100

Using a simple empirical approach, we analyze world and regional‐level cohort replacement as determined by the key components of population dynamics, i.e. fertility, survival, and migration, for 1950–2010, using UN data. We define two kinds of homeostatic relationships among these components: fertility responses to mortality change (type I) and migration responses to changes in net reproduction (type II), and show that both can be observed to some degree in this period. We examine the extent of cohort replacement embodied in the medium‐variant UN population projections over 2010–2100 and consider how the international migration assumptions made in such projections would be affected by a homeostatic perspective.     

BANK COMPETITION AND CONSUMER SEARCH OVER CREDIT CARD INTEREST RATES

This article models bank competition facing consumers with different search incentives and finds that consumers with higher credit card balances have lower interest rates given their risk class due to their greater search effort. It also finds that a default history leads to higher interest rates. The equilibrium interest rate corresponding to risk type and motive (borrowing versus convenience/transactions) is derived theoretically, and the determinants of the interest rate are estimated using an original data set. Endogeneity of default is handled with a two-equation system.(JEL D14 , D12 , D11 )