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2021 ◽  
Vol 8 (4) ◽  
pp. 159-169
Author(s):  
Ashok Kumar Panigrahi ◽  
Kushal Vachhani ◽  
Suman Kalyan Chaudhury

We all must agree that the word "trend" is now the buzzword of the stock market. As a part of investment strategy and analysis, it is always suggested that the investors should keep an eye on medium-term and short-term changes in addition to longer-term (secular) patterns. Traders and investors use the RSI as a momentum indicator. Overbought and oversold situations are indicated by RSI values between 70 and 30. Over the past two decades, several techniques have been developed to analyze NIFTY 50 data for investment purposes. In this paper, we have estimated the returns by looking at the two trends i.e., 50-50 and 60-40. In addition to this, how to trade and back-test our strategy is also explained. Applying these two RSI strategies to the NIFTY 50 chart revealed that 50-50 offers a higher long-term return, while 60-40 provides a superior short-term return. Finally, the strategies' returns F-statistics and P-values were calculated and analyzed to determine their significance level and acceptability.


2021 ◽  
Author(s):  
◽  
Irina Ilyushkina

<p>Declines in global marine finfish catches, which accounts for ~15% of the animal protein consumed by humans, has caused a 6-fold increase in total reported catch of invertebrates since 1950. This has led to the over-exploitation and decline of many marine invertebrate fisheries. The red rock lobster (Jasus edwardsii) fishery is New Zealand’s most economically valuable inshore fishery. The current management strategy relies on the assumption that the stock is comprised of a single panmictic population. However, more recent studies have challenged the genetic homogeneity of Jasus edwardsii across the Tasman sea and described high levels of self-recruitment in a Stewart Island subpopulation. A disregard for the underlying genetic structure in the management of a fishery can lead to excessive removal of individuals from populations contributing to the overall genetic diversity of the stock and thus reduce the species adaptability. The ability to adapt to new environments is particularly important in the context of global climate change and can significantly affect the long-term sustainability of the stock. Thus, the goal of this study was to identify specific patterns of genetic diversity of Jasus edwardsii population and provide an interpretation and assessment of the impact on the NZ fishery. The first objective was to optimize and validate molecular and bioinformatic protocols of Single Nucleotide Polymorphism (SNP) discovery for the red rock lobster Jasus edwardsii. The double digest restriction-site associated DNA (ddRADseq) protocol was optimized for the relatively large red rock lobster genome, which also has a high paralog content. The impact of bioinformatic processing on the population genetic inferences was then assessed by testing three different SNP discovery pipelines with the Rad-loci pipeline producing the most optimal marker discovery rate with a low level of missing data and a low SNP error rate. An analysis of technical replicates confirmed the reproducibility of both the molecular and bioinformatic protocols and also the validated the data generation process suitable for population genetic analyses. The second objective of my thesis was to investigate the genetic structure and population connectivity of adult red rock lobsters. The SNPs discovered were characterised as selectively neutral or under divergent selection (outlier) and both types of markers were analysed using Bayesian model-based clustering (STRUCTURE), non model-based multivariate analysis (Discriminant Analysis of Principal Components (DAPC)) and F-statistics. A lack of population differentiation using neutral genetic markers indicated a high level of gene flow and connectivity between populations. In contrast, there was evidence for selective pressure as a result of the analysis of outlier markers. Three main regions were identified: North-East NZ, North-West NZ and South NZ sub-populations, as part of a larger NZ metapopulation (FST ranged from 0.025 to 0.049, P < 0.001). The results of this study suggested that high levels of gene flow and connectivity are counteracted to some extent by the local selection that promotes the survival and reproduction of locally adapted genotypes. However, the strength of this selective pressure still permits low levels of survival and reproduction of non-optimal genotypes causing allele frequency homogenisation of the new generation of lobsters. The third objective was to investigate the levels of connectivity and adaptive divergence of the red rock lobster pueruli/juvenile lobsters for comparison with pattern of divergence of adult lobster in order to investigate the mechanisms of population structure formation. A suite of Bayesian clustering, non-model multivariate analysis and F-statistics were employed in the assessment of neutral and outlier markers developed for pueruli/juveniles. Similar to adult lobsters, pueruli/juveniles were characterised by a low level of divergence of the neutral markers indicating effective larvae dispersal. Outlier markers detected population differentiation patterns likely to originate from a phenotype – environment mismatch resulting in post-settlement mortality of non-adapted genotypes. The similarity between patterns of genetic divergence of adult lobsters and late juvenile/early juveniles indicates that post-settlement mortality, driven by local environmental conditions, has most likely occurred on earlier developmental stages of Jasus edwardsii, which were not possible to sample in my study.  The final objective was to explore environment–genotype associations of Jasus edwardsii. Biological Environment Stepwise (BEST) analyses, redundancy analyses (RDA) and generalized linear modelling (GLM) consistently indicated a correlation between the annual amplitude of sea surface temperature (SST) and adaptive population divergence. In addition, an influence of spatial distribution on the patterns of adaptive population differentiation was also detected via RDA. From these results I propose a mechanism underlying the patterns of population differentiation discovered in Chapters 3 and 4: a latitudinal gradient of SST appears to be the selective force promoting the adaptive divergence of the lobster populations with local patterns of connectivity distorting the gradient and thus forming three distinct temperature adapted genotypes (North-West, North-East, and South). An environmental association analysis offered 43 candidate loci, which after alignment of transcriptome-mapped reference catalog sequences to annotated protein databases identified a candidate gene for thermal adaptation - UDP-glycosyltransferase (UGT). UGT is a detoxification enzyme involved in the metabolization of a variety of endogenous and environmental compounds and its activity and gene expression patterns have been linked to temperature. This study provides evidence for the local adaptations of the NZ population of Jasus edwardsii to SST, which together with the efficient mechanism of larval dispersal creates a system likely resilient to changes in temperature. This feature is important in the light of climate change-induced range shifts and supports the long-term sustainability of the red rock lobster fishery. The three genetically distinct regions identified coincide with existing boundaries of the management units and therefore do not require an adjustment of the current management regime.</p>


2021 ◽  
Author(s):  
◽  
Irina Ilyushkina

<p>Declines in global marine finfish catches, which accounts for ~15% of the animal protein consumed by humans, has caused a 6-fold increase in total reported catch of invertebrates since 1950. This has led to the over-exploitation and decline of many marine invertebrate fisheries. The red rock lobster (Jasus edwardsii) fishery is New Zealand’s most economically valuable inshore fishery. The current management strategy relies on the assumption that the stock is comprised of a single panmictic population. However, more recent studies have challenged the genetic homogeneity of Jasus edwardsii across the Tasman sea and described high levels of self-recruitment in a Stewart Island subpopulation. A disregard for the underlying genetic structure in the management of a fishery can lead to excessive removal of individuals from populations contributing to the overall genetic diversity of the stock and thus reduce the species adaptability. The ability to adapt to new environments is particularly important in the context of global climate change and can significantly affect the long-term sustainability of the stock. Thus, the goal of this study was to identify specific patterns of genetic diversity of Jasus edwardsii population and provide an interpretation and assessment of the impact on the NZ fishery. The first objective was to optimize and validate molecular and bioinformatic protocols of Single Nucleotide Polymorphism (SNP) discovery for the red rock lobster Jasus edwardsii. The double digest restriction-site associated DNA (ddRADseq) protocol was optimized for the relatively large red rock lobster genome, which also has a high paralog content. The impact of bioinformatic processing on the population genetic inferences was then assessed by testing three different SNP discovery pipelines with the Rad-loci pipeline producing the most optimal marker discovery rate with a low level of missing data and a low SNP error rate. An analysis of technical replicates confirmed the reproducibility of both the molecular and bioinformatic protocols and also the validated the data generation process suitable for population genetic analyses. The second objective of my thesis was to investigate the genetic structure and population connectivity of adult red rock lobsters. The SNPs discovered were characterised as selectively neutral or under divergent selection (outlier) and both types of markers were analysed using Bayesian model-based clustering (STRUCTURE), non model-based multivariate analysis (Discriminant Analysis of Principal Components (DAPC)) and F-statistics. A lack of population differentiation using neutral genetic markers indicated a high level of gene flow and connectivity between populations. In contrast, there was evidence for selective pressure as a result of the analysis of outlier markers. Three main regions were identified: North-East NZ, North-West NZ and South NZ sub-populations, as part of a larger NZ metapopulation (FST ranged from 0.025 to 0.049, P < 0.001). The results of this study suggested that high levels of gene flow and connectivity are counteracted to some extent by the local selection that promotes the survival and reproduction of locally adapted genotypes. However, the strength of this selective pressure still permits low levels of survival and reproduction of non-optimal genotypes causing allele frequency homogenisation of the new generation of lobsters. The third objective was to investigate the levels of connectivity and adaptive divergence of the red rock lobster pueruli/juvenile lobsters for comparison with pattern of divergence of adult lobster in order to investigate the mechanisms of population structure formation. A suite of Bayesian clustering, non-model multivariate analysis and F-statistics were employed in the assessment of neutral and outlier markers developed for pueruli/juveniles. Similar to adult lobsters, pueruli/juveniles were characterised by a low level of divergence of the neutral markers indicating effective larvae dispersal. Outlier markers detected population differentiation patterns likely to originate from a phenotype – environment mismatch resulting in post-settlement mortality of non-adapted genotypes. The similarity between patterns of genetic divergence of adult lobsters and late juvenile/early juveniles indicates that post-settlement mortality, driven by local environmental conditions, has most likely occurred on earlier developmental stages of Jasus edwardsii, which were not possible to sample in my study.  The final objective was to explore environment–genotype associations of Jasus edwardsii. Biological Environment Stepwise (BEST) analyses, redundancy analyses (RDA) and generalized linear modelling (GLM) consistently indicated a correlation between the annual amplitude of sea surface temperature (SST) and adaptive population divergence. In addition, an influence of spatial distribution on the patterns of adaptive population differentiation was also detected via RDA. From these results I propose a mechanism underlying the patterns of population differentiation discovered in Chapters 3 and 4: a latitudinal gradient of SST appears to be the selective force promoting the adaptive divergence of the lobster populations with local patterns of connectivity distorting the gradient and thus forming three distinct temperature adapted genotypes (North-West, North-East, and South). An environmental association analysis offered 43 candidate loci, which after alignment of transcriptome-mapped reference catalog sequences to annotated protein databases identified a candidate gene for thermal adaptation - UDP-glycosyltransferase (UGT). UGT is a detoxification enzyme involved in the metabolization of a variety of endogenous and environmental compounds and its activity and gene expression patterns have been linked to temperature. This study provides evidence for the local adaptations of the NZ population of Jasus edwardsii to SST, which together with the efficient mechanism of larval dispersal creates a system likely resilient to changes in temperature. This feature is important in the light of climate change-induced range shifts and supports the long-term sustainability of the red rock lobster fishery. The three genetically distinct regions identified coincide with existing boundaries of the management units and therefore do not require an adjustment of the current management regime.</p>


2021 ◽  
Vol 9 (11) ◽  
pp. 1207-1220
Author(s):  
Awonuga Oluwatomilayo Omotoyosi ◽  
◽  
Alalade Yimka S.A. (Ph.D) ◽  

The manufacturing sector in Nigeria is characterized by liquidity challenges due to the rising cost of energy, multiple taxations, high-interest rates, poor accessibility to loans and foreign exchange instability which affect profitability. However, the right mix of capital structure is said to correlate with profitability. This study, therefore, determined the effect of capital structure on the profitability of selected manufacturing companies in Nigeria. Employing ex-post facto design, secondary data from 10 manufacturing firms were captured. The Hausman test determined the suitability of random effects panel regression to estimate the effect of capital structure variables on ROE and ROA. The four hypotheses of the study were tested at the 5% level of significance. Results of the study showed that capital structure has a significant effect on return on equity (ROE) with an Adjusted R-squared value of 0.876871 and F- statistics of 236.0122, on return on asset (ROA) with an Adjusted R-squared value of 0.080555 and F- statistics of 3.891215. The study concluded that although the capital structure is vital to the profitability of firms it is not adequately planned in manufacturing firms in Nigeria and has hampered the profitability. The study recommended that manufacturing firms must make good decisions relating to their capital structure if earnings must improve.


2021 ◽  
Vol 13 ◽  
pp. 413-418
Author(s):  
Jinqi Song

Firstly, this paper proposes F statistic whose limit distribution and critical values are also provided to test nonlinearity and structure change with unit root in TV-ESTAR model framework. The results show that the distribution of F statistic is nonstandard. Then, this paper analyzes finite sample characteristics of F statistics through the Monte Carlo simulation and founds F statistics has better power than kss statistics in Kapetanios et al to test nonlinear unit root with structure change.


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2250
Author(s):  
Mario Valerio Velasco-García ◽  
Carlos Ramírez-Herrera ◽  
Javier López-Upton ◽  
Juan Ignacio Valdez-Hernández ◽  
Higinio López-Sánchez ◽  
...  

Dioon holmgrenii De Luca, Sabato et Vázq.Torres is an endangered species; it is endemic and its distribution is restricted to the biogeographic province of the Mexican Pacific Coast. The aim of this work was to determine the diversity and genetic structure of nine populations. The genetic diversity parameters and Wright’s F statistics were determined with six microsatellite loci. The genetic structure was determined by using the Structure software and by a discriminant analysis. The genetic diversity of the populations was high. The proportion of polymorphic loci was 0.89, the observed heterogeneity was higher (Ho = 0.62 to 0.98) than expected (He = 0.48 to 0.78), and the fixation index was negative (IF = −0.091 to −0.601). Heterozygous deficiency (FIT = 0.071) was found at the species level and heterozygotes excess (FIS = −0.287) at the population level. The genetic differentiation between populations was high (FST = 0.287), with the number of migrants less than one. Three groups of populations were differentiated, and the variation within populations, between populations, and between groups was: 65.5, 26.3, and 8.2%, respectively. Multiple factors explain the high genetic diversity, while the genetic structure is due to geographic barriers. Community reserves are urgent in at least one most diverse population of each group.


PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258181
Author(s):  
Stéphane de Palmas ◽  
Derek Soto ◽  
Ming-Jay Ho ◽  
Vianney Denis ◽  
Chaolun Allen Chen

Mesophotic habitats could be sheltered from natural and anthropogenic disturbances and act as reproductive refuges, providing propagules to replenish shallower populations. Molecular markers can be used as proxies evaluating the connectivity and inferring population structure and larval dispersal. This study characterizes population structure as well as horizontal and vertical genetic connectivity of the broadcasting coral Pocillopora verrucosa from Ludao, a small oceanic island off the eastern coast of Taiwan. We genotyped 75 P. verrucosa specimens from three sites (Gongguan, Dabaisha, and Guiwan) at three depth ranges (Shallow: 7–15 m, Mid-depth: 23–30 m, and Deep: 38–45 m), spanning shallow to upper mesophotic coral reefs, with eight microsatellite markers. F-statistics showed a moderate differentiation (FST = 0.106, p<0.05) between two adjacent locations (Dabaisha 23–30 and Dabaisha 38–45 m), but no differentiation elsewhere, suggesting high levels of connectivity among sites and depths. STRUCTURE analysis showed no genetic clustering among sites or depths, indicating that all Pocillopora individuals could be drawn from a single panmictic population. Simulations of recent migration assigned 30 individuals (40%) to a different location from where they were collected. Among them, 1/3 were assigned to deeper locations, 1/3 to shallower populations and 1/3 were assigned to the right depth but a different site. These results suggest high levels of vertical and horizontal connectivity, which could enhance the recovery of P. verrucosa following disturbances around Ludao, a feature that agrees with demographic studies portraying this species as an opportunistic scleractinian.


2021 ◽  
pp. 1-24
Author(s):  
Hannes Leeb ◽  
Lukas Steinberger

Abstract We study linear subset regression in the context of the high-dimensional overall model $y = \vartheta +\theta ' z + \epsilon $ with univariate response y and a d-vector of random regressors z, independent of $\epsilon $ . Here, “high-dimensional” means that the number d of available explanatory variables is much larger than the number n of observations. We consider simple linear submodels where y is regressed on a set of p regressors given by $x = M'z$ , for some $d \times p$ matrix M of full rank $p < n$ . The corresponding simple model, that is, $y=\alpha +\beta ' x + e$ , is usually justified by imposing appropriate restrictions on the unknown parameter $\theta $ in the overall model; otherwise, this simple model can be grossly misspecified in the sense that relevant variables may have been omitted. In this paper, we establish asymptotic validity of the standard F-test on the surrogate parameter $\beta $ , in an appropriate sense, even when the simple model is misspecified, that is, without any restrictions on $\theta $ whatsoever and without assuming Gaussian data.


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