INSIGHTS ON COMPETITION FROM A SCIENCE-BASED ANALYSIS

The work presented here uses a science-based approach to obtain new understandings on the mechanisms and the ramifications of competition in everyday life. Assuming competition of a Darwinian nature we can deduce an S-shaped pattern for growth in most competitive environments. Examples range from a rabbit population growing in a fenced-off grass field to scientists competing for Nobel-Prize awards. There are secrets embedded in the mathematical law that describes growth in competition. The rate of growth being proportional to the amount of growth already achieved makes beginnings difficult and sheds light on such proverbial wisdom as “you need goal to make gold”. It also argues for the necessity to engage teachers in the learning process. Other revelations are linked to the symmetry of a life-cycle pattern, which possesses predictive power and demystifies the easy-come-easy-go phenomenon. Predictive power characterizes the rapid-growth phase of the S-shaped pattern (rheostasis) as well as the end of the pattern when growth reaches a ceiling (homeostasis) where supply and demand are in equilibrium. The latter phenomenon is best exemplified by society’s tolerance of deadly car accidents because deaths from car accidents have remained at an invariant level for many decades reflecting equilibrium. The mathematical equation for growth in competition when cast in discrete form reveals fluctuations of chaotic nature before and after the rapid-growth phase. This can illuminate the turbulent times before and after the formation of the USSR as well as the tumultuous times of the 1930s in America. Extending the quantitative approach to two species competing in the same niche involves introducing coupling constants that account for how one species impacts the growth rate of the other. A celebrated example is the predator-prey relationship, which is only one of six possible interactions all of which can be encountered in the marketplace where products and companies compete like species. There are six possible dimensions for action in a two-species competitive struggle that can be exploited toward managing competition and setting one’s role/image in the marketplace. An example dealt in detail is the evolution of the number of American Noble-Prize winners whose numbers are not about to begin diminishing. Americans are involved in a win-win competitive struggle with non-American scholars, but Americans are drawing more of a benefit.

The Best Years of Older Europeans’ Lives

This paper offers new evidence on the life-cycle pattern of happiness. A novelty of the analysis is that it exploits information on the period individuals recall as the happiest in their lives. Data come from SHARELIFE 2008/09, a retrospective life survey conducted in 13 European countries among individuals aged 50 or more. Using this information, I build a longitudinal data set that extends across the whole lifespan of respondents. The probability of living a happiest year in life at each age is estimated through a conditional fixed effects logit model. Results show that the likelihood of living the happiest period in life exhibits a concave relationship with age, with a turning point at about 30–34 years and a decreasing trend from that point onward. Retrospectively, midlife is not perceived as the least likely happiest period in life. These patterns persist even after controlling for usual correlates of subjective well-being, and they are rather stable across cohorts and genders despite presenting certain variability across European countries.

Abundance of microarthropods population in different sites of Midnapore east coast of West Bengal, India

Soil represents one of the most important reservoirs of biodiversity. Soil fauna is an important reservoir of biodiversity and plays an essential role in several soil ecosystem functions; furthermore it is often used to provide soil quality indicators. An ecological study of microarthropods communities from East Midnapore coast, West Bengal, India was undertaken. Four different biotopes were studied over the course of 30 months. A total 44 species of soil microarthropods were studied in details with regard to seasonal population fluctuation, variation in their community structure, relationship with physiochemical parameters of soil, life cycle pattern and their functional role in the ecosystem.

Household Debt and Delinquency over the Life Cycle

This paper uses loan-level data from Thailand's National Credit Bureau to study household debt over the life cycle of borrowers. We decompose two aggregate and commonly used measures of debt—debt per capita and delinquency rate—into components that unveil the extensive and intensive margins of household indebtedness. We find a striking inverted-U life-cycle pattern of indebtedness as predicted by economic theories. However, peaks are reached at different ages for different loan products and different lenders. We also find that debt has expanded over time for all age groups. Younger cohorts seem to originate debt earlier in their lives than older generations. Meanwhile, older borrowers remain indebted well past their retirement age. Finally, we find a downward pattern of delinquency over the life cycle. Our findings have important policy implications on financial access and distress of households as well as on economic development and financial stability of the economy.

Wealth Effects on Consumption in Malta: Evidence from Household Level Data

This paper attempts to examine for the first time the effects of household wealth on consumption in Malta, based on household level data from the 2017 Household Finance and Consumption Survey (HFCS). The estimation of the log-log consumption function is performed using OLS regression, after taking into account the survey design. The results provide evidence in support of the existence of a wealth effect on consumption, stemming from housing and financial wealth. In particular, the housing wealth effect on consumption is positive and higher than the financial wealth effect for the whole sample size, especially for homeowners. In addition, comparisons in the differences in wealth effects across age groups confirm the existence of a life-cycle pattern in consumption.

Relative growth and population dynamics of Macrobrachium iheringi (Decapoda, Palaemonidae)

During the ontogenetic development of crustaceans, the relative growth of some structures may change, especially during the transition from juvenile to adult. This study describes the relative growth of body structures of Macrobrachium iheringi, and provides information on its population dynamics, such as structure, fecundity, and morphological sexual maturity. The sampling of M. iheringi was carried out in “Ribeirão da Hortelã”, in Botucatu (SP, Brazil). The length of the carapace (CL), abdomen (AL), and ischium (IL), merus (ML), carpus (CrL), propodus (PpL), and dactyl (DcL) of the second right pereopod were measured. In addition, the width of the second abdominal pleura (PW) and propodus height (PpH) were included in analyses. The relationships that best demonstrated the changes in the allometric coefficient were CL vs PpL in males and females. The CL, in which males and females reach morphological sexual maturity, was estimated as 13.3 mm and 11.1 mm, respectively. The sex-ratio differed from the expected 1:1 and was skewed towards females. Precipitation and temperature influenced the abundance of different demographic classes. Macrobrachium iheringi has few but large eggs, which is expected since this species has an abbreviated larval development. Based on these results, we conclude that the propodus are good indicators of the size at onset of morphological sexual maturity. In addition, important information was obtained on the biology of M. iheringi, including its life cycle pattern, reproduction and influence of abiotic factors.

SEBARAN DAN HABITAT JUVENIL UDANG PENAEID DI PERAIRAN KUBU RAYA,KALIMANTAN BARAT

Tingkat keterkaitan juvenil udang terhadap habitat dapat dijadikan salah satu dasar untuk penentuan kawasan daerah asuhan. Penelitian tentang sebaran dan keterkaitan antara juvenil udang penaeid dengan habitatnya dilakukan di perairan Kubu Raya, Kalimantan Barat pada bulan Juni, September, November (tahun 2012) dan bulan April, Juli, Oktober (tahun 2013). Pengambilan sampel dilakukan dengan metode sapuan (swept area method)menggunakan mini beam trawl. Indeks constancy dan fidelity digunakan untukmengetahui pola sebarandan derajat keterkaitan udang penaeid dengan habitatnya sebagai dasar penentuan daerah asuhan juvenil udang. Identifikasi juvenil udang diperoleh 3 genera dan 12 spesies. Kelimpahan total tertinggi berasal dari genus Metapenaeus (70,5%), diikuti genus Parapenaeopsis (29,3%) dan Fenneropenaeus (0,2%). Juvenil udang dari genera tersebut memiliki pola sebaran dan preferensi habitat yang berbeda karena memiliki perbedaan pola daur hidup. Juvenil udangwangkang (F. indicus)memiliki derajat keterkaitan dengan kategori sangat tinggi di perairan Tanjung Bunga Dalam, sedangkan derajat keterkaitan dengan kategorimediumterdapat di perairan Tanjung Intandan Pulau Dabung. Habitat daerah asuhan udangwangkang terutama terdapat di daerah estuari dengan kerapatan mangrove cukup tinggi, mendapat massa air tawar secara langsung dengan tipe substrat pasir bercampur lumpur dan serasah. Udang dogol putih (M. elegans) dan udang rotan (P.gracillima)memiliki derajat keterkaitan dengan kategori mediumdi perairan Tanjung Tempurung. Habitat daerah asuhan yang disenangi adalah daerah estuaria yang memiliki banyak masukan massa air tawar dan air laut atau sangat dipengaruhi oleh proses pasang-surut dengan tipe substrat terdiri dari lumpur dan pasir serta banyak serasah.Habitat preference of juvenile shrimps as an indicator to determine of main shrimp nursery ground. Study on distribution and habitat preference of juvenile penaeid shrimps in Kubu Raya waters,West Kalimantan were carried out on June, September, November (2012) and April, July, October (2013). Sampling was conducted with a sweep area method using a mini beam trawl. Distribution pattern and habitat preference of juvenile shrimps were analyzed by constancy and fidelity index. Identification of juvenile penaeid shrimp consisted of 3 genera and 12 species with the highest of total abundance from genus ofMetapenaeus (70.5%), followed by Parapenaeopsis (29.3%) and Fenneropenaeus (0.2%). Juvenile shrimp for those genera have different distribution patterns in certain habitats because of different life cycle pattern. The habitat preference of indian white shrimp juvenile (F. indicus) in the waters of Tanjung Bunga Dalam have very high category. Meanwhile, in the waters of Tanjung Intan and Pulau Dabung has medium category. The main nursery ground of F. indicus were estuaries with high enough of mangrove density and most affected by freshwater discharge with the dominant substrate type is sandas sandly mud and mix with litters. The habitat preference of Juvenile of fine shrimp (M. elegans) and thin shrimp (P. gracillima) have medium category in the waters of Tanjung Tempurung. The main nursery ground characterneeds estuaries that have a lot of freshwater and saltwater mass input depending on the tides with substrate type are mud, sand and mix with litters.

CAPITAL TAXES, LABOR TAXES AND THE HOUSEHOLD

We study the impact of capital and labor taxation in an economy where couples bargain over the intrahousehold allocation under limited commitment. In this framework more wealth improves commitment and gives rise to insurance gains within the household. Our theory motivates these gains by the empirical observation that wealth, in contrast to labor income, is a commonly held resource within households. Based on this observation we study whether eliminating capital taxes from the economy, and raising labor taxes to balance the government’s budget, may generate welfare gains to married households. We illustrate that the quantitative effects from this reform are rather small. We attribute the small effects to the life cycle pattern of wealth accumulation and to the impact of labor income taxes on household risk sharing: In particular, we show that higher labor taxes may make the limited commitment friction more severe, even though they may make the distribution of labor income more equitable within the household.