Components Analysis of a Density-Dependent Catchability Coefficient in a Salmon Hook and Line Fishery

1993 ◽  
Vol 50 (3) ◽  
pp. 513-520 ◽  
Author(s):  
Thomas F. Shardlow
Keyword(s):  
Marine Environment ◽  
Empirical Studies ◽  
Past Research ◽  
Fishing Effort ◽  
Fish Abundance ◽  
Fishing Gear ◽  
Density Dependent ◽  
Components Analysis ◽  
The Relationship

The relationship between the catch per unit of effort (C/E) of salmon anglers and salmon abundance was determined by using simultaneous estimates of both C/E and salmon density (n). Salmon in their natural marine environment were observed as they approached fishing gear. The components of catch, such as the number of fish approaching, attacking, and biting the lure per unit of fishing effort, were recorded. C/E was not linearly related to density because the estimate of the catchability coefficient q increased with abundance. This result contrasts with previous empirical studies of catchability in which q declined with fish abundance. However, because only historical catch records had been used to estimate catchability, the interactions between the fishing gear and fish were not available in past research. This study suggests that feeding facilitation among salmon may be the mechanism underlying increased catchability with abundance.

Business uncertainty and financial leverage: should the firm double up on risk?

2019 ◽  
Vol 45 (4) ◽  
pp. 536-544
Author(s):  
Khaled Elkhal
Keyword(s):  
Financial Distress ◽  
Empirical Studies ◽  
Past Research ◽  
Optimum Level ◽  
Business Risk ◽  
Financial Leverage ◽  
Research Papers ◽  
Content Type ◽  
The Cost ◽  
The Relationship

Purpose The purpose of this paper is to examine the nature of the relationship between business risk and financial leverage. While past theoretical and empirical studies on this topic use similar variables, overall, their findings are inconclusive. In this paper, the author contends this is partially due to inappropriate proxies for business risk that are commonly used in these research papers. To correct for this misspecification, this paper proposes an alternative proxy for business risk that is isolated from the effects of financial leverage. Design/methodology/approach Past research on the relationship between business risk and financial leverage uses some variations in a firm’s operating cash flow as a proxy for business risk. This proxy cannot solely reflect business risk and may very well be affected by the level of financial leverage, especially for financially distressed firms. This paper proposes an alternative proxy for business risk that is isolated from the effects of financial leverage. This proxy is the cost of capital of an all-equity firm. The theoretical model developed in this paper is based on deriving the optimum level of debt as a function of business risk in the context of the Modigliani and Miller Proposition II model. Findings The findings show a positive linkage between business risk and financial leverage. This relationship is robust to the various forms the cost of financial distress function may take. Originality/value The mixed findings in past research papers regarding the relationship between business risk and financial leverage are mainly due to “inappropriate” measures of business risk that do not only reflect one firm attribute and are contaminated with other factors mainly financial leverage. As such, since the variable of interest is misspecified, the outcome of these studies cannot be credible. This paper attempts to correct for such misspecification by proposing a proxy that only reflects business risk. In addition, the proposed model is based on the widely acceptable Modigliani and Miller static theory of capital structure.

Natural resource sustainability and poverty reduction

2000 ◽  
Vol 5 (3) ◽  
pp. 241-258 ◽  
Author(s):  
CHRISTOPHER HEADY
Keyword(s):  
Decision Making ◽  
Numerical Model ◽  
Natural Resource ◽  
Poverty Reduction ◽  
Fishing Effort ◽  
Fish Migration ◽  
Fishing Gear ◽  
Resource Sustainability ◽  
Management Policies ◽  
The Relationship

This paper uses a model of an inland fishery in Bangladesh to investigate the relationship between poverty and resource sustainability in a specific case. It makes use of detailed fieldwork to build a numerical model of fishery decision making, which incorporates extensions to standard fisheries models. In particular, it includes fish migration between lease units and models the choice of fishing gear, as well as fishing effort, over the year. The modelling of fishing gear choice allows an analysis of the effect of management policies on employment in the fishery, a major factor that influences poverty in the locality. The numerical results show that while some simple policies to improve sustainability are likely to increase poverty, it is possible to design policies which affect gear choice and lead to reduced poverty without harming the sustainability of the resource.

Density-Dependent Mortality and the Relationship between Size Composition and Fishing Effort in Lobster Populations

1986 ◽  
Vol 43 (11) ◽  
pp. 2360-2367 ◽  
Author(s):  
J. T. Addison
Keyword(s):  
Time Series Data ◽  
Stock Assessment ◽  
Size Composition ◽  
Fishing Effort ◽  
Series Data ◽  
Density Dependent ◽  
Density Dependent Mortality ◽  
Yield Per Recruit ◽  
The Relationship ◽  
Dependent Mortality

Examination of time series data from lobster fisheries shows that although in some cases fishing mortality (estimated from size composition data) is directly related to fishing effort, that of many stocks remains relatively unchanged despite changes in the pattern of exploitation. This suggests that conventional stock assessment models used for finfish populations may not be adequate for lobster populations. A model is described which incorporates into a standard yield per recruit model density-dependent mortality in large lobsters due to limited availability of suitable holes in the substrate. The model predicts that size composition may change little with changes in fishing effort, and it is shown that current stock assessment methods may fail to detect those changes. The underlying assumptions of current methods are undermined further by the possible delay of moulting of lobsters that cannot find shelters.

Visual Evoked-Response Correlates of Speechreading Performance in Normal-Hearing Adults

1983 ◽  
Vol 26 (1) ◽  
pp. 2-9 ◽  
Author(s):  
Vincent J. Samar ◽  
Donald G. Sims
Keyword(s):  
Multiple Correlation Coefficient ◽  
Evoked Response ◽  
Multiple Correlation ◽  
Potential Significance ◽  
Visual Evoked Response ◽  
Latency Measure ◽  
Two Measures ◽  
Components Analysis ◽  
The Relationship ◽  
Visual Evoked

The relationship between the latency of the negative peak occurring at approximately 130 msec in the visual evoked-response (VER) and speechreading scores was investigated. A significant product-moment correlation of -.58 was obtained between the two measures, which confirmed the fundamental effect but was significantly weaker than that previously reported in the literature (-.90). Principal components analysis of the visual evoked-response waveforms revealed a previously undiscovered early VER component, statistically independent of the latency measure, which in combination with two other components predicted speechreading with a multiple correlation coefficient of S4. The potential significance of this new component for the study of individual differences in speechreading ability is discussed.

Urbanization impacts on production and recruitment of Fundulus heteroclitus in salt marsh creeks

2020 ◽  
Vol 645 ◽  
pp. 187-204
Author(s):  
PJ Rudershausen ◽  
JA Buckel
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Fundulus Heteroclitus ◽  
Multiple Factor Analysis ◽  
Southeastern Usa ◽  
Density Dependent ◽  
Dependent Relationship ◽  
Juvenile Abundance ◽  
The Relationship ◽  
Throw Trap

It is unclear how urbanization affects secondary biological production in estuaries in the southeastern USA. We estimated production of larval/juvenile Fundulus heteroclitus in salt marsh areas of North Carolina tidal creeks and tested for factors influencing production. F. heteroclitus were collected with a throw trap in salt marshes of 5 creeks subjected to a range of urbanization intensities. Multiple factor analysis (MFA) was used to reduce dimensionality of habitat and urbanization effects in the creeks and their watersheds. Production was then related to the first 2 dimensions of the MFA, month, and year. Lastly, we determined the relationship between creek-wide larval/juvenile production and abundance from spring and abundance of adults from autumn of the same year. Production in marsh (g m-2 d-1) varied between years and was negatively related to the MFA dimension that indexed salt marsh; higher rates of production were related to creeks with higher percentages of marsh. An asymptotic relationship was found between abundance of adults and creek-wide production of larvae/juveniles and an even stronger density-dependent relationship was found between abundance of adults and creek-wide larval/juvenile abundance. Results demonstrate (1) the ability of F. heteroclitus to maintain production within salt marsh in creeks with a lesser percentage of marsh as long as this habitat is not removed altogether and (2) a density-dependent link between age-0 production/abundance and subsequent adult recruitment. Given the relationship between production and marsh area, natural resource agencies should consider impacts of development on production when permitting construction in the southeastern USA.

Spotting a liar by looking for microexpressions: Challenges and Opportunities

2019 ◽  
Author(s):  
Xunbing Shen
Keyword(s):  
Empirical Evidence ◽  
Deception Detection ◽  
Empirical Studies ◽  
High Stake ◽  
Challenges And Opportunities ◽  
Cues To Deception ◽  
The Relationship

Microexpressions do exist, and they are regarded as valid cues to deception by many researchers, furthermore, there is a lot of empirical evidence which substantiates this claim. However, some researchers don’t think the microexpression can be a way to catch a liar. The author elucidates the theories predicting that looking for microexpressions can be a way to catch a liar, and notes that some data can support for the utilization of microexpressions as a good way to detect deception. In addition, the author thinks that the mixed results in the area of investigating microexpressions and deception detection may be moderated by the stake. More empirical studies which employ high-stake lies to explore the relationship between microexpressions and deception detection are needed.

Humans and the Environment

2013 ◽  
Keyword(s):  
Spatial Scales ◽  
Empirical Studies ◽  
Human Action ◽  
Cultural Practice ◽  
Environmental Archaeology ◽  
Archaeological Data ◽  
Temporal And Spatial ◽  
Global And Local ◽  
The Relationship ◽  
The Way

The environment has always been a central concept for archaeologists and, although it has been conceived in many ways, its role in archaeological explanation has fluctuated from a mere backdrop to human action, to a primary factor in the understanding of society and social change. Archaeology also has a unique position as its base of interest places it temporally between geological and ethnographic timescales, spatially between global and local dimensions, and epistemologically between empirical studies of environmental change and more heuristic studies of cultural practice. Drawing on data from across the globe at a variety of temporal and spatial scales, this volume resituates the way in which archaeologists use and apply the concept of the environment. Each chapter critically explores the potential for archaeological data and practice to contribute to modern environmental issues, including problems of climate change and environmental degradation. Overall the volume covers four basic themes: archaeological approaches to the way in which both scientists and locals conceive of the relationship between humans and their environment, applied environmental archaeology, the archaeology of disaster, and new interdisciplinary directions.The volume will be of interest to students and established archaeologists, as well as practitioners from a range of applied disciplines.

Preliminary observations on abundance and distribution of fish fauna in a canyon of the Bay of Biscay (ICES Division 8c)

2021 ◽  
pp. 1-10
Author(s):  
G. Diez ◽  
L. Arregi ◽  
M. Basterretxea ◽  
E. Cuende ◽  
I. Oyarzabal
Keyword(s):  
Deep Sea ◽  
Basque Country ◽  
Fish Fauna ◽  
Fishing Effort ◽  
Fishing Gear ◽  
Clear Trend ◽  
Depth Ranges ◽  
Abundance And Distribution ◽  
Sea Fish ◽  
Distribution Of Fish

Abstract The changes in abundance and biodiversity of deep-sea fish fauna are described based on an annual deep-water longline survey with data collected during the period 2015–2019 in the Basque Country continental Slope (ICES Division 8c). The sampling scheme included hauls in four 400 m strata, from 650–2250 m deep. The DST sensors installed in the main line have allowed us to set an accurate soak time for each haul, and they were used to calculate fishing effort and CPUE by haul. The catchability of the fishing gear indicated that 15% of the total hooks deployed in the five-year period were able to fish, and that the bottom longline was very effective in fishing a wide number of different species in all depth ranges. The fishing gear caught 14 different species of sharks (13 deepwater and one pelagic), two chimaeras and nine teleosts. The abundance and biomass registered on the hooks attached to the bottom were between three and four times higher than in the floating sections, and the highest CPUE and biomass were recorded between 1051–1450 m, from 2015 to 2017, and in the 1451–1850 m strata, but they do not show any clear trend throughout the five years of the series.

scholarly journals “When” Does It Pay to Be Good? Attributions Mediate the Way CSR Elements Impact on Consumer Responses, and Are Controllable

2021 ◽  
Vol 13 (11) ◽  
pp. 5869
Author(s):  
Athanasios Krystallis ◽  
Vlad Zaharia ◽  
Antonis Zairis
Keyword(s):  
Past Research ◽  
Consumer Response ◽  
Multiple Mediation ◽  
Consumer Responses ◽  
Mediating Role ◽  
Consumer Attributions ◽  
The Right ◽  
The Relationship ◽  
Experimental Survey

Responding to the appeal for more research on the contingencies that shape the relationship between CSR and corporate performance, this paper incorporates environmental CSR, sets up an experimental survey and employs multiple mediation analysis with the aim to test the mediating role of consumer attributions on the CSR elements–consumer responses relationship; and further to examine the degree to which attributions are controllable, i.e., specific CSR elements activate specific type of attributions. Results support that attributions have a strong predicting power on consumer outcomes. The right time of appearance and the appropriate amount of resources committed to a CSR campaign, through the dual type of attributions they activate (more positive, i.e., values-driven and less negative, i.e., egoistic), impact positively on consumer reactions. In this respect, the study adds to past research showing that attributions are controllable, i.e., specific CSR initiative characteristics of a impact on the dimensionality of attributions and, through that, on specific target-types of consumer responses. This study thus shows that the activation of a dual-level attributions’ system is ambivalent, dependent on the character of the CSR campaign. The fact that specific CSR elements (i.e., CSR Timing) activate dual-level CSR motives that act complementarily indicates that managers should be clear about the capabilities of the elements of their CSR initiatives and how much impact they expect those elements to have on consumer response.

scholarly journals The Construct of Subjective Economic Inequality

2021 ◽  
pp. 194855062199686
Author(s):  
Anita Schmalor ◽  
Steven J. Heine
Keyword(s):  
Economic Inequality ◽  
Past Research ◽  
Objective Measures ◽  
Subjective Measure ◽  
Psychological Variables ◽  
American Sample ◽  
Key Variables ◽  
The Relationship ◽  
Measures Of Inequality

Economic inequality has been associated with a host of social ills, but most research has focused on objective measures of inequality. We argue that economic inequality also has a subjective component, and understanding the effects of economic inequality will be deepened by considering the ways that people perceive inequality. In an American sample ( N = 1,014), we find that some of the key variables that past research has found to correlate with objective inequality also correlate with a subjective measure of inequality. Across six countries ( N = 683), we find that the relationship between subjective inequality and different psychological variables varies by country. Subjective inequality shows only modest correlations with objective inequality and varies by sociodemographic background.

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