Faculty Opinions recommendation of Information constraints and the precision of adaptation: sex ratio manipulation in wasps.

Author(s):  
Bryant McAllister
2008 ◽  
Vol 27 (07) ◽  
pp. 617-619 ◽  
Author(s):  
M. Wittmann ◽  
E. Haen ◽  
H. Spießl ◽  
H. Hausner

ZusammenfassungZahlreiche epidemiologische Studien zeigen, dass sich das Geschlechterverhältnis der Prävalenz depressiver Erkrankungen ab der 6. Lebensdekade – also nach der weiblichen Menopause – wieder annähert. Wir haben untersucht, ob sich dieser epidemiologische Effekt auch in der stationären Versorgung abbildet. Unter Verwendung der AGATE-Stichtagsdaten der Jahre 2000 bis 2004, wurde der Zusammenhang zwischen Geschlecht und Alter bei stationär behandelten depressiven Patienten analysiert. Der Zusammenhang zwischen Geschlechterverhältnis und dem Alter wurde mithilfe des Korrelationskoeffizienten nach Spearman sowie mit χ2-Test untersucht. In der 5. und 6. Lebensdekade lag die Sex-Ratio F/M bei 1,7:1, sie stieg in der 7. Dekade auf 2,2:1 und in der 8. Dekade auf 2,6:1 an. Anders als aufgrund epidemiologischer Studien zu erwarten wäre, nähert sich in der stationär psychiatrischen Versorgung das Verhältnis depressiver Patienten im Alter nicht an. Depressive ältere Männer sind also im stationären Versorgungssystem unterrepräsentiert.


Author(s):  
Ivan V. Rozmainsky ◽  
Yulia I. Pashentseva

The paper is devoted to the economic analysis of rationality in the tradition of Harvey Leibenstein: the authors perceive rationality as “calculatedness” when making decisions, while the degree of this “calculatedness” is interpreted as a variable. Thus, this approach does not correspond to the generally accepted neoclassical interpretation of rationality, according to which rationality is both full and constant. The authors believe that such a neoclassical approach makes too stringent requirements for the abilities of people. In real life, people do not behave like calculating machines. The paper discusses various factors limiting the degree of rationality of individuals. One group of factors is associated with external information constraints such as the complexity and extensiveness of information, as well as the uncertainty of the future. Another group of factors is related to informal institutions. In particular, the paper states that the system of planned socialism contributes to less rationality than the system of market capitalism. Thus, in the post-socialist countries, including contemporary Russia, one should not expect a high degree of rationality of the behavior of economic entities. The paper mentions, in particular, the factors of rationality caused by informal institutions, such as the propensity to calculate, the propensity to be independent when making decisions and the propensity to set goals. The authors also believe that people who live on their own are usually more rational than people who share a common household with someone else. This assumption is verified econometrically based on data on young urban residents collected by the authors. It turned out that the behavior of people included in this database, in general, corresponds to what the authors believed.


Author(s):  
Ma. Dulce C. Guillena

Gonado-somatic index and fecundity are tools for measuring the sexual maturity and ability of animals to reproduce.  This study investigates the reproduction of Trichiurus lepturus. Specifically, this aimed to determine the sex ratio, the GSI, the relationship between fecundity and total length, fecundity and total weight, fecundity and ovary weight. The Descriptive Method of research was used.  Percentage and chi-square was utilized in determining the percentage of occurrence and sex ratio respectively.   Pearson r Product Moment Coefficient of Correlation was used to determine the relationships of the parameters. The study revealed that females outnumbered males and the sex ratio for different month showed significant difference.  Spawning season was observed to occur in November and December as revealed in its GSI values and it synchronized with the full and new moon phases.  Fecundity is positively correlated with body weight, body size, and ovary weight where ovary weight is observed to be the best index for fecundity.  The results of this study could be used further for formal stock assessment of cutlassfish fishery.


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