Fisherian Theory Research Articles

English

The generalized Fisher effect has attracted a great deal of controversy around the world. This is similar in the Nigerian scenario as study established that there exist no long-run relationship between stock returns and inflation while some studies reported that only a unidirectional causation of returns on stocks with money flow exist as the variation in the flow of money will alter returns on stocks significantly, but not in the opposite direction. Therefore, this study examined the relationship between stock returns, inflation and interest rate in Nigeria with objective of testing the Fisherian theory. The Fisherian theory of interest postulates that changes in the value of money would be reflected in nominal interest rates and stock returns in the same proportion over the long-run. This study tested the validity of this hypothesis in a small open economy, Nigeria. A battery of econometric techniques were employed (descriptive and inferential) for the sake of robustness. In line with the theoretical postulation of the Fisherian theory of interest, the findings established a long-run relationship among the selected series. Specifically, the study found that the price level coefficient exhibits a positive and significant relationship with stock price in the long-run. Therefore, evidence abounds of a great deal of the Fisherian postulation in the analyses carried out and conclude that common stocks are, indeed, a good hedge against inflation in Nigeria.   Key words: Fisherian theory, interest rates, Nigeria, small open economy, stock returns.

Male-skewed sex ratio in Myrica esculenta: a dioecious tree species

The population of M. esculenta tends to deviate from the equilibrium of expected 1:1 primary sex ratio predicted by Fisherian theory. Populations of dioecious plants may often exhibit biased sex ratios, which generally favour males. A study on reproductive potential, i.e., pollen production and female flower production, and reproductive success in Myricaesculenta was assessed in three diameter (diameter at breast height: dbh at 1.37 m) classes, i.e., small (10–20 cm), medium (20–30 cm), and large (30–40 cm). Population structure and sex ratio was determined in transects in four major associations of Myricaesculenta, i.e., (i) with mixed Oak-Rhododendron forest (ii) with Chir Pine–Oak forest, (iii) with pure Oak forest, and (iv) with pure Deodar forest. The sex ratio of trees was male-biased. Male frequency was higher in lower diameter classes and maximum on resource-poor site. More female individuals were recorded in higher-diameter classes and resource rich location, indicating that the total reproductive cost in M. esculenta is greater in female trees than that of the male trees. The population of M.esculenta tends to deviate from the equilibrium of expected 1:1 primary sex ratio predicted by Fisherian theory. The male trees demonstrated greater survival, especially in resource-poor conditions, which was reflected strongly biased sex ratios within the lower size classes. The study would be helpful for formulating appropriate silvicultural and genetic management strategies for this species.

The dynamics of sex ratio evolution Dynamics of global population parameters

Classical formalizations of the Fisherian theory of sex ratio evolution are based on the assumption that the number of grand offspring of a female serves as a measure of fitness. However, the classical population genetics approach also considers the contribution of male individuals to gene proliferation. The difference between the predictions of phenotypic and genetic models is that the phenotypic approach describes the primary sex ratio of 0.5 as the ESS value, while genetic models describe the stable state of a population by a combination of the stable states of the male and female subpopulations. In this paper, we formulate an alternative model of sex ratio evolution that is focused on the dynamics and quantitative properties of this process and that combine a rigorous genetic approach with a game theoretic strategic analysis. In the new model, females are the strategic agents and males are the passive carriers on unexpressed genes. Fitness functions in the new model are derived with respect to a “fitness exchange” effect, i.e. the contribution of male individuals to female fitness and vice versa. This new model shows that the dynamics of this system are complex and consist of two phases. The first, rapid, phase converges the system to a stable manifold (termed the male subpopulation equilibrium—MSE) where the male subpopulation state is in equilibrium, conditional on the current state of the female subpopulation. Double phase dynamics occur when the population state is not compatible with the current strategic composition of the population (determined by the value of the primary sex ratio) which can be caused by ecological factors. The trajectory of convergence to the MSE can be very complicated and may contain a dramatic change in the primary sex ratio. Thus, the primary sex ratio of 0.5 is unstable for perturbations of gene frequencies among male carriers. Therefore, the new model supports predictions of genetic models that the evolutionary stability of the sex ratio should be characterized by a combination of a stable value of the primary sex ratio and the male subpopulation equilibrium.

Secondary Sex Ratios in Six Snake Species

Sex ratios at birth or hatching in snake populations are often assumed to be 1∶1 in agreement with Fisherian theory. We evaluated secondary sex ratios (SSRs) in two viperids (Sistrurus catenatus and S. miliarius) and four natricine colubrids (Nerodia rhombifer, Thamnophis proximus, T. radix, and T. sirtalis). We captured 274 gravid females that produced 2443 living offspring. Population-level SSRs in our focal species did not differ significantly from 1∶1. In addition, variation in individual litter SSRs conformed to expectations generated by the binomial distribution with an even sex ratio. Each species showed individual variation in SSRs; however, the majority of variation in litter SSRs was not explained by variation in the maternal or litter characteristics we examined. The three exceptions were a very strong negative association between mean offspring mass and litter SSR in T. radix (r2 = 0.96), a strong positive association between mean offspring mass and litter sex ratio in T. proximus (r2 = 0.40), and a strong positive association between maternal condition and litter SSR in T. proximus (r2 = 0.40). Whether or not these relationships have functional or adaptive significance warrants further study. The majority of our results were unsurprising and not statistically significant. We suggest, however, that the presentation and publication of both non-significant and significant results is exactly what is needed to give an accurate view of SSRs at both the population level and the maternal level in snakes.

Stock returns, inflation and interest rates in the United Kingdom

The Fisherian theory of interest asserts that a fully perceived change in inflation would be reflected in nominal interest rates and stock returns in the same direction in the long run. This paper examines the Fisherian hypothesis of asset returns using alternative techniques of linear regression, and vector error correction models to examine the nature of the relationship between stock returns and inflation in the UK. Consistent with the Fisherian hypothesis, empirical evidence in the linear regression model suggests a positive and statistically significant relationship between stock returns and inflation, which regards common stock as a good hedge against inflation. The results based on the unit root and cointegration tests indicate a long-run reliable relationship between price levels, share prices, and interest rates which could be interpreted as the long-run determinants of stock returns. The findings also suggest a bidirectional relationship between stock returns and inflation. The evidence of a significant Fisher effect is robust across model specifications.

Individual disease risk and multimetric analysis of Crohn disease

Rare dominant genes with high penetrance can be identified by linkage without inbreeding, whereas rare recessive genes with high penetrance are most efficiently recognized by autozygosity mapping of homozygotes in pedigrees with preferential inbreeding. On the contrary, complex inheritance is characterized by common genes with low penetrance, for which family studies and inbreeding are inefficient. Here, we develop the Fisherian theory for diallelic cases and controls, show that it compares favorably with Bayesian estimates, and evaluate their currently low power for discriminating cases and controls in Crohn disease (CD). Significance is enhanced by inclusion of composite likelihood, but identification of causal loci is delayed by low recognition of gene function. Clearly, association mapping is not yet optimal, and so strenuous effort is justified to develop a more inclusive gene map and association tests more powerful than single markers and the current use of composite likelihood. Because of its relatively high heritability and the correspondingly large number of detected causal loci, CD presents an ideal test system to determine the power and flaws of competing methods of whole-genome case/control association analysis in publicly available data. Until such a test is exploited by competing statisticians, their Herculean efforts will be inconclusive, and the costly advances from increased sample size will be suboptimal and disappointing.

REIT Returns and Inflation: Perverse or Reverse Causality Effects?

Contrary to the Fisherian theory of interest, previous studies document a negative relationship between REIT (Real Estate Investment Trust) returns and inflation. In this research, we re-examine this perverse inflation behavior by testing for the causal relationships among REIT returns, real activity, monetary policy, and inflation through a vector error correction model. Our results indicate that the observations of REIT returns as perverse inflation hedges are spurious. The observed negative relationship between REIT returns and inflation is in fact a manifestation of the effects of changes in monetary policies. These findings are consistent with Darrat and Glascock's (1989) evidence of monetary effects on REIT returns.

Sex ratios of sea turtles

AbstractEstimates of sex ratios of hatchling sea turtles range from approximately 50% female (Chelonia mydas and Dermochelys coriacea in Suriname) to approximately 90% female (Caretta caretta in Florida). Seasonal sex production profiles (SSPPs) show how similar overall sex ratios can be achieved in dissimilar ways. Possible explanations of the data include sampling error, constraints on evolutionary adjustment of pivotals or behavior to local thermal conditions, and violations of assumptions required by classical Fisherian theory. © 1994 Wiley‐Liss, Inc.

New parametric measures of information

In this paper methods are presented for obtaining parametric measures of information from the non-parametric ones and from information matrices. The properties of these measures are examined. The one-dimensional parametric measures which are derived from the non-parametric are superior to Fisher's information measure because they are free from regularity conditions. But if we impose the regularity conditions of the Fisherian theory of information, these measures become linear functions of Fisher's measure.

Rational Choice and Patterns of Growth

Concluding his excellent survey of recent monetary theory, Harry Johnson [4] suggested that future developments in this field should come from attempts break monetary theory loose from the mould of short-run equilibrium analyses, conducted in abstraction from the process of economic growth and accumulation, and to integrate it with the rapidly developing theoretical literature on economic growth. This paper summarizes an attempt to deal with these issues. Like most theoretical work in rapidly growing fields, it is incomplete and the assumptions on which it is based are relatively crude abstractions. These abstractions, however, allow us to explore certain aspects of the interaction of the real and the monetary phenomena in a model of economic growth in which money, being government noninterest bearing debt, is introduced as an alternative asset to real capital. Most of the recent work in this field 1 has centered on the analysis of the patterns of growth of a monetary economy by postulating alternative plausible saving functions and demand functions for money. What differentiates this product is the fact that, in line with Patinkin's [6] presentation of the neoclassical theory of money, and with the classical Fisherian theory of saving [2], it is based on an explicit analysis of individuals' saving behavior, viewed as a process of wealth accumulation aimed at maximizing some intertemporal utility function. The first part of the paper describes the representative economic unit