Stock

Reducing overfishing and recovering overfished fish stocks is a challenging and important global problem. Rebuilding targets are essential ingredients for guiding overfished stocks to recovery. Having robust estimates of rebuilding targets is likely a necessary condition for effective long-term management of fishery resources. In this paper, we show how Bayesian model averaging can be applied to estimate rebuilding targets under alternative hypotheses about stock–recruitment dynamics. Using alternative hypotheses about stock–recruitment dynamics and environmental variation is important because using only a single hypothesis can lead to substantially different reference points and policy implications. The alternative hypotheses are augmented with prior information collected from meta-analyses of stock–recruitment data to construct a set of age-structured production models. We illustrate our approach using three overfished New England groundfish stocks. We fit alternative model likeli...

Problem statement: The stock exchange market has been one of the most popular investments in the recent past due to its high returns. The market has become an integral part of the global economy to the extent that any fluctuation in this market influences personal and corporate financial lives and the economic health of a country. The daily behavior of the market prices revealed that the future stock prices cannot be predicted based on past movements. Approach: In this study, we analyzed the behavior of daily return of Nigerian stock market prices. The sample included daily market prices of all securities listed in the Nigeria Stock Exchange (NSE). Results: The result from the study provided evidence that the Nigerian stock exchange is not efficient even in weak form and that NSE follow the random walk model. The idealized stock price in the Nigerian stock exchange is a martingale. Conclusion: Martingale defines the fairness or unfairness of the investment and no investor can alter the stock price as defined by expectation.

The taxonomic composition of the metazoan parasites found in the stomach of 629 specimens of the "Patagonian toothfish" Dissostichus eleginoides Smitt, 1898, from two localities in southern Chile (Lebu 36 • 00 S; Quellón 48 • 49 S), is recorded. More than 58,000 parasite specimens belonging to 9 taxa were registered. Adult worms were represented by the hemiurids Gonocerca phycidis Manter 1925, Lecithochirium genypteri Luhe 1905, Brachyphallus crenatus (Rudolphi 1802), and Derogenes varicus (Muller 1784) and the nematode Hysterothylacium sp. Ward & Magath 1917. Larval forms of anisakid nematodes, an acanthocephalan (Corynosoma sp.), a trypanorhynch cestode (Hepatoxylon trichiuri (Holten 1802)) and an unidentified pseudophyllidean cestode were also obtained. Parasitological evidence, based on univariate and multivariate analysis, does not support either the existence of discrete stocks, migratory movements between areas or seasonality in pattern of infection.

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The shortfin mako shark (Isurus oxyrinchus) is a cosmopolitan species abundant in the Northwest Pacific. Some aspects of its biological information have been well documented yet its population dynamics is poorly known. The objective of this study is to assess the population status of the shortfin mako in the Northwest Pacific. The whole weights of 68,943 female and 64,338 male shortfin mako landed at Nanfangao and Chengkung fish markets, eastern Taiwan from 1990 to 2004 were converted to total length and the age for each individual was estimated based on the sex-specific von Bertalanffy growth equation. Total mortality obtained with length-converted catch curves ranged from 0.175 yr −1 to 0.272 yr −1 for females and from 0.196 yr −1 to 0.286 yr −1 for males. Natural mortality estimated from Peterson and Wroblewski's equation were 0.077-0.244 yr −1 for females and 0.091-0.203 yr −1 for males. Based on virtual population analysis, the highest fishing mortality occurred in ages 6-10 years for females and 7-12 years for males. Increases of fishing mortality in ages 3-5 years for females and 3-6 years for males since 1996 indicated that the young shortfin mako experienced higher fishing pressure in recent years. Both deterministic and stochastic simulations showed that annual spawning potential ratio (SPR) of shortfin mako was lower than the biological reference point (BRP) of SPR 35% and had a decreasing trend since 2000. Current fishing mortality (0.066 yr −1) was greater than the BRP of F 30% (0.052 yr −1), F 35% (0.045 yr −1), F 40% (0.04 yr −1) and F 0.1 (0.063 yr −1) suggesting that this stock might have been overexploited. Therefore, to ensure sustainable utilization, a management measure of 32% reduction of current fishing effort was suggested for the shortfin mako stock in the Northwest Pacific.

We compared growth in a domesticated strain of coho salmon (Oncorhynchus kisutch), that had been selected for rapid growth over 16 generations, to that of its hatchery-origin unselected parental stock. Fish were spawned on the same date and incubated under similar conditions. First feeding fry were fed to satiation and then were fed a commercial salmon feed at two ration levels, either to satiation or on a fixed ration from the size at which the smallest fish could accept a 1-mm pellet (domesticated 0.65 g, hatchery 0.96 g). The domesticated fish outperformed unselected fish by growing faster and to a larger size, ingesting a greater amount of feed when fed to satiation, and exhibiting greater efficiency in feed conversion. When fed to satiation, domesticated fish ingested 53% more feed and gained 78% more weight compared to unselected fish. The selected fish also appeared to utilize dietary lipids for energy while sparing protein for growth, while unselected fish deposited dietary lipids as body fat. These results indicate that selection over 16 generations for growth also resulted in changes in feed efficiency and energy allocation. Understanding the mechanisms underlying improved growth will aid future selection studies by identifying multiple targets of selection that contribute most to growth.

Since the 1970s, when major improvements to the water quality were made, the River Thames has been subject to a high-profile project aimed at restoring Atlantic salmon to the catchment. Whilst initially successful, with hundreds of salmon returning each year in the late 1980s, the number of adults returning to the river has declined steeply again in recent years, reaching a low in 2005 when no salmon were recorded. Using a baseline of genetic information gathered from 3830 salmon from throughout their southern European range, and incorporating samples from the hatchery fish used to stock the Thames, all 10 tagged hatchery fish captured in 2003 and all 16 returning untagged adult salmon captured between 2005 and 2008 were assigned to their most likely river of origin. The results suggest that untagged salmon currently ascending the river originate not from exogenous fish stocked into the Thames, but predominantly from other rivers in southern England. This highlights the potential for natural processes of recolonisation to operate in rivers where salmon have become locally extirpated. These findings also underscore several important considerations when undertaking species restoration projects: (i) previous causes of declines must be sufficiently ameliorated to allow new/translocated individuals to thrive, (ii) introduced individuals should originate from a stock that is closely related to the extirpated population, according to the principles of contemporary conservation biology, and (iii) dispersal and gene-flow from neighbouring populations may play a significant role in establishing new populations.► Despite an intensive hatchery stocking programme, since 2005 no hatchery reared salmon have been caught in the Thames. ► Genetic assignment analysis indicates that wild salmon ascending the Thames originate from other rivers in southern England. ► Wild salmon returning to the Thames between 2005 and 2008 do not originate from exogenous fish stocked into the Thames. ► Such straying highlights the potential for natural recolonisation of rivers where salmon have become locally extirpated. ► Our findings highlight the futility of long-term stocking without corresponding improvements in habitat and water quality.

Various aspects of cultural conditions were investigated in an effort to design an efficient selective breeding scheme for tilapia. High density culture has the potential of reducing confounding environmental effects associated with fish behavior. Body size of fry reared through 56 days Ž . was not affected by any of the stocking densities used 10-200 fryrl with uniform water inflow. However, when water inflow was proportional to fish density, high density culture of fingerlings Ž . 18 fishrl did appear to promote growth and result in improved normality of the distribution of Ž . Ž . body size relative to fish stocked at lower 2 fishrl or higher 200 fishrl densities. Although this could be interpreted as a consequence of diminished social interactions, a definitive conclusion could not be made in the absence of direct observational data on individual fish. Mixed-model methodology was used to estimate genetic parameters for body size. Estimated heritability for body weight was about 0.25 for all ages from 56 to 126 days. Phenotypic and genetic correlations among body weights at various ages were positive and near unity. q

The goal of this paper is to model the impact of oil prices on Vietnam's stock prices. We use daily data for the period 2000-2008 and include the nominal exchange rate as an additional determinant of stock prices. We find that stock prices, oil prices and nominal exchange rates are cointegrated, and oil prices have a positive and statistically significant impact on stock prices. This result is inconsistent with theoretical expectations. The growth of the Vietnamese stock market was accompanied by rising oil prices. However, the boom of the stock market was marked by increasing foreign portfolio investment inflows which are estimated to have doubled from US$0.9 billion in 2005 to US$1.9 billion in 2006. There was also a change in preferences from holding foreign currencies and domestic bank deposits to stocks local market participants, and there was a rise in leveraged investment in stock as well as investments on behalf of relatives living abroad. It seems that the impact of these internal and domestic factors were more dominant than the oil price rise on the Vietnamese stock market.

Inventory is often the largest priced asset of a business after the fixed asset. Keeping the inventory also means keeping a tab on the realizable value, market value of all the stocks, stock in production and finished stock. This paper explores the challenges of manual inventory management system for supermarkets and infers solutions to the current challenges by designing a computerized inventory management system to order and update the stocks. The main method used for this research work is interview. Data were collected from 5 heterogeneous supermarkets and used as a tool for obtaining facts. When the goods were supplied the update of the stocks were being taken from time to time. The finding shows the challenges facing the manual system of inventory management system; the manual system requires everyday counting of items in the inventory, human errors are very prevalent during counting and recording and in case of disaster like fire or flood or poor communication, all the manual ...

Câu 1: Người sở hữu cổ phiếu và trái phiếu đều được hưởng: a. Lãi suất cố định b. Thu nhập phụ thuộc vào hoạt động của công ty c. Được quyền bầu cử tại Đại hội cổ đông d. Lãi suất từ vốn mà mình đầu tư vào cống ty Câu 2: Nhà đầu tư mua 10 trái phiếu có mệnh giá 100 USD, có lãi suất danh nghĩa 6%/năm với giá 900 USD. Vậy hàng năm nhà đầu tư sẽ nhận được tiền lãi là: a. 60 USD b. 600 USD c. 570 USD d. 500 USD Câu 3: Cổ phiếu quỹ: a. Được chia cổ tức. b. Là loại cổ phiếu được phát hành và được tổ chức phát hành mua lại trên thị trường. c. Người sở hữu có quyền biểu quyết. d. Là một phần cổ phiếu chưa được phép phát hành. Câu 4: Các câu nào sau đây đúng với thị trường sơ cấp a. Làm tăng lượng vốn đầu tư cho nền kinh tế. b. Làm tăng lượng tiền trong lưu thống. c. Không làm tăng lượng tiền trong lưu thông. d. Giá phát hành do quan hệ cung cầu quyết định Câu 5: Thị trường thứ cấp a. Là nơi các doanh nghiệp huy động vốn trung và dài hạn thông qua việc phát hành CP và TP b. Là nơi mua bán các loại CK kém chất lượng. c. Là nơi mua bán các chứng khoán đã phát hành. d. Là thị trường chứng khoán kém phát triển Câu 6: Đối với công chúng đầu tư, tài liệu nào quan trọng nhất trong hồ sơ đăng ký phát hành ra công chúng: a. Bản sao giấy phép thành lập và đăng ký kinh doanh. b. Danh sách và sơ yếu lý lịch tành viên Hội đồng Quản Trị và Ban giám đốc. c. Đơn xin phép phát hành. d. Bản cáo bạch. Câu 7: Trật tự ưu tiên lệnh theo phương thức khớp lệnh là: a. Thời gian, giá, số lượng. b. Giá, thời gian, số lượng. c. Số lượng, thời gian, giá. d. Thời gian, số lượng, giá.

تعد البورصة من أهم الآليات التي تساعد الدول على جذب الاستثمار إليها من جهة وتمويل الاستثمارات المتواجدة بها من جهة أخرى، وهو ما دفع إلى تحليل دور بورصة الجزائر في هذا المجال. وقد هدفت الدراسة إلى التعرف على مدى التأثير التي تفرضه بورصة الجزائر في استقطاب الاستثمارات، وللوصول إلى ذلك تم الاعتماد على المنهجين الوصفي والتحليلي. وقد توصلت الدراسة إلى أن بورصة الجزائر، وبالرغم من قدم تاريخ إنشائها، إلا أنها لا تزال ترتب ضمن أضعف البورصات العالمية والعربية حيث أن حجم التداول بها لا يزال ضعيفا مقارنة بالمعدلات العالمية، كما أنها لا تستقطب إلا خمس مؤسسات جزائرية دون تسجيل مؤسسات أجنبية، ولا حتى حركة نشطة فعلية من قبل مؤسسات جزائرية أخرى.  The stock market is one of the most important mechanisms that help countries to attract investment on the one hand, and financing of existing investments on the other hand, which prompted to examine the role of Algeria stock exchange in this area. The study aimed to identify the extent of the impact imposed by the Algeria stock exchange in attracting investments. To reach this aim, the study relied on the descriptive and analytical approaches, and it has concluded that the Algeria Stock Exchange still arranged within the weaker global and Arab stock exchanges where the volume of trading is still weak compared with international rates. It also do not attract only five Algerian companies without foreign companies registered, not even a real active movement by other Algerian companies.

Agency theory is used to expand the research in strategic human resource management (SHRM) by viewing the construct underlying SHRM as control over all employees. We develop hypotheses on the effects of CEO ownership, administrative HRM, and incentive stock ownership on firm performance. The results indicate that administrative HRM has a negative effect on stock price. Incentive alignment via stock ownership has a positive effect on stock price and productivity. CEO ownership has a positive effect on sales but a negative impact on productivity. Implications for theory and practice are discussed. Agency Theory Implications for SHRM WP 96-17

A stock market, equity market or share market is the aggregation of buyers and sellers (a loose network of economic transactions, not a physical facility or discrete entity) of stocks (also called shares); these may include securities listed on a stock exchange as well as those only traded privately.

The risk-return trade off: Expected and required return Abstract Traditional economic models state that riskier investments should have a higher expected return. Psychological models of choice showed that people is influenced by the kind of information they are provided with and by the context of the choice, since they do not have a stable order of preferences but, rather, they construct it while giving a judgment. Experiment 1 showed that people consider the expected return of an equity only when it is explicitly stated, rather than computing it on the basis of the expected outcomes and probabilities. Experiment 2 and 3 showed that people judgments about the expected return of a stock are influenced by the way they are required to provide their estimates. In Experiment 2 participants' judgments were inconsistent with the risk-return trade off, whereas in Experiment 3 people asked a higher return from a riskier stock than from a safer one. Implications of the results for investors' behavior are discussed.

Econophysics is a science in its infancy, born about ten years ago at this time of writing, at the crossing roads of physics, mathematics, computing and of course economics and finance. It also covers human sciences, because all economics is ultimately driven by human decision. From this human factor, econophysics has no hope to achieve the status of an exact science, but it is interesting to discover what can be achieved, discovering potential limits and trying try to push further away these limits. A few data analysis techniques are described with emphasis on the Detrended Fluctuation Analysis (DF A) and the Zipf Analysis Technique (ZAT ). Information about the original data aresketchy, but the data concerns mainly the foreign currency exchange market. The robustness of the DF A technique is underlined. Additional remarks are given for suggesting further work. Models about financial value evolutions are recalled, again without going into elaborate work discussing typical agent behaviors, but rather with hopefully sufficient information such that the basic ingredients can be memorized before reading some of the vast literature on price formation.

Game theory Shared stocks Dynamic externality Fisheries economics Cooperative management a b s t r a c t Thirty years have passed since Munro published his 1979 work on the potential applications of game theory to fisheries. It is pertinent to ask now: has this potential been realized, and in what forms? This paper highlights progress in the field over the past three decades. We begin our review with the early two-player dynamic game-theoretic analyses. Next, we illustrate how coalition theory has been brought in over the past decade to allow the modeling of games with greater than two players, and how coalitional externalities, a major issue in international and shared fish stocks management, have been incorporated recently. Finally, we highlight new areas for game theory to come into its own in fisheries, which will most definitely include the potential for catch rights in international shared-stock fisheries, as well as ecosystem dynamics to be modeled in a game-theoretic context. As game theory can offer insights into the challenges of achieving cooperative fisheries management, we hope the next decade of fisheries economics research will include a bigger leap from academic game theory exercises to impacting policy decisions.

We find evidence of significant price manipulation at the stock level by hedge funds on critical reporting dates. Stocks in the top quartile by hedge fund holdings exhibit abnormal returns of 30 basis points in the last day of the month and a reversal of 25 basis points in the following day. Using intraday data, we show that a significant

Models capable of estimating losses in future earthquakes are of fundamental importance for emergency planners and for the insurance and reinsurance industries. One of the main ingredients in a loss model is an accurate, transparent and conceptually sound algorithm to assess the seismic vulnerability of the building stock and indeed many tools and methodologies have been proposed over the past 30 years for this purpose. This paper takes a look at some of the most significant contributions in the field of vulnerability assessment and identifies the key advantages and disadvantages of these procedures in order to distinguish the main characteristics of an ideal methodology.

Growth of homogenous sized groups was studied in captive populations of Senegalese sole (Solea senegalensis Kaup) juveniles. An initial sole population was graded and three different sole stocks were obtained according to their respective size to form the homogenous ...

Eutrophication constitutes a serious threat to many European lakes and many approaches have been used during the past 20-30 years to improve lake water quality. Results from the various lake restoration initiatives are diverse and the long-term effects are not well described.

We describe a method for determining reasonable yield and management reference points for data-poor fisheries in cases where approximate catches are known from the beginning of exploitation. The method, called Depletion-Based Stock Reduction Analysis (DB-SRA), merges stochastic Stock-Reduction Analysis with Depletion-Corrected Average Catch. Data requirements include estimates of historical annual catches, approximate natural mortality rate and age at maturity. A production function is specified based on general fishery knowledge of the relative location of maximum productivity and the relationship of MSY fishing rate to the natural mortality rate. This leaves unfished biomass as the only unknown parameter, which can be estimated given a designated relative depletion level near the end of the time series. The method produces probability distributions of management reference points concerning yield and biomass. Uncertainties in natural mortality, stock dynamics, optimal harvest rates, and recent stock status are incorporated using Monte Carlo exploration. Comparison of model outputs to data-rich stock assessments suggests that the method is effective for estimating sustainable yields for data-poor stocks.

Forty-five different parasite taxa were recorded from 1919 Atlantic horse mackerel Trachurus trachurus caught at 20 stations in a study area from off the coast of Morocco to south-west Norway, and throughout the Mediterranean Sea. Eleven taxa are new host records, and one is probably a new species. The geographical distribution and biology of each parasite and its value for the stock identification of T. trachurus are described and discussed. The most effective biological tags were the larval nematodes Anisakis spp. and Hysterothylacium aduncum. The distinctive pattern of infection with these nematodes observed in samples from the single North Sea station clearly distinguishes this from all other stations and supports the current management strategy which treats the North Sea population as a separate stock. The distinction between the putative "western", "southern" and "mauritanian" stocks is less clear, with evidence of considerable mixing between them. The highly localised distributions of some parasites in the Mediterranean part of the study area suggest that T. trachurus populations there appear to comprise three main stocks-western, central and eastern. There is also strong evidence of the migration of fish from Atlantic populations into the extreme western part of the Mediterranean.

The Guinea Current Large Marine Ecosystem (GCLME) extending from Bissagos Island (Guinea Bissau) in the north to Cabinda (Angola) in the south defines the shared transboundary waters off the coast of western Africa, which embodies some of the major coastal upwelling sub-ecosystems of the world and is an important centre of marine biodiversity and marine food production. The GCLME is characterized by distinctive bathymetry, hydrography, chemistry, and trophodynamics and represents the number 28 Large Marine Ecosystem (LME) ranked among the most productive coastal and offshore waters in the world with rich fishery resources. However, over-exploitation of fisheries, pollution from domestic and industry sources, habitat destruction and poorly planned and managed coastal developments and near-shore activities are resulting in a rapid depletion of the rich fisheries resources and degradation of vulnerable coastal and offshore habitats putting the economies, productivity and health of the populace at risk. Recognizing the urgency of the fisheries decline and the environmental and socio-economic consequences for the region, the 16 countries bordering the ecosystem have mobilized complementary resources to the funding from the Global Environment Facility and United Nations Industrial Development Organization to implement priority management actions agreed in the preliminary Strategic Action Programme for the recovery of depleted fish stocks and restoration of degraded habitats for the advancement of the achievement of the World Summit on Sustainable Development (WSSD) Johannesburg Plan of Implementation targets for recovery of fish stocks.

A proper understanding of the management status of small-scale subsistence and artisanal fisheries requires not only detailed sociocultural study, but comprehensive analysis of the state of the fished population(s), using rigorous stock assessment and other fisheries biology tools. In this article I describe several approaches taken to assess the artisanal trochus fishery at West Nggela. This includes stock density and other data, that demonstrate many reefs are overfished. I discuss the social and economic factors influencing the performance of the fishery. The importance of an understanding of property tenure is dealt with in some detail. An analysis of the various categories of fishers' ecological knowledge about trochus is also presented, and discussed with respect to the categories of biological and ecological information considered by most fisheries biologists as essential to the assessment and management of a fishery.

Under the United Nations Framework Convention on Climate Change (UNFCCC), Non-Annex 1 countries such as Kenya are obliged to report green house gas (GHG) emissions from all sources where possible, including those from soils as a result of changes in land use or land management. At present, the convention encourages countries to estimate emissions using the most advanced methods possible, given the country circumstances and resources. Estimates of soil organic carbon (SOC) stocks and changes were made for Kenya using the Global Environment Facility Soil Organic Carbon (GEFSOC) Modelling System. The tool conducts analysis using three methods: (1) the Century general ecosystem model; (2) the RothC soil C decomposition model; and (3) the Intergovernmental Panel on Climate Change (IPCC) method for assessing soil C at regional scales. The required datasets included: land use history, monthly mean precipitation, monthly mean minimum and maximum temperatures for all the agro-climatic zones of Kenya and historical vegetation cover. Soil C stocks of 1.4-2.0 Pg (0-20 cm), compared well with a Soil and Terrain (SOTER) based approach that estimated $1.8-2.0 Pg (0-30 cm). In 1990 48% of the country had SOC stocks of <18 t C ha À1 and 20% of the country had SOC stocks of 18-30 t C ha À1 , whereas in 2000 56% of the country had SOC stocks of <18 t C ha À1 and 31% of the country had SOC stocks of 18-30 t C ha À1 . Conversion of natural vegetation to annual crops led to the greatest soil C losses. Simulations suggest that soil C losses remain substantial throughout the modelling period of 1990-2030. All three methods involved in the GEFSOC System estimated that there would be a net loss of soil C between 2000 and 2030 in Kenya. The decline was more marked with RothC than with Century or the IPCC method. In non-hydric soils the SOC change rates were more pronounced in high sandy soils compared to high clay soils in most land use systems. #

A time series abundance analysis of adult and juvenile Haliotis fulgens living in the central region of Baja California Sur, Me´xico, was performed and its potential application to fishery management as a predictor of future catches was assessed. The juvenile time series consisted of 13 y (1996 to 2008) of semiannual sampling of abalone juveniles from 2 sites in Bahı´a Tortugas, Baja California Sur, whereas the adult time series encompassed 15 y (1996 to 2010) at the same fishing area. The time series were based on separate density and biomass surveys of the abalone population conducted annually by the Instituto Nacional de la Pesca for setting catch quotas in all abalone fishing areas. Various lagged linear regressions and quadratic regressions were tested to explore the correlations between 1-y-old recruits and $3-, 4-, and 5-y-old adults; the reverse order was also evaluated (adults of various ages and 1-y-old recruits). The only significant quadratic regression captured the 3-y delay between #1-y-old juveniles and 4-y-old adults (r ¼ 0.702, P ¼ 0.014). Smoothed series for both adults and recruits revealed that the abundance of recruits #1 y old was reflected 3 y later in the abundance of 4-y-old adults. The importance of a predictive model such as this one lies primarily in its good approximation of future catches, enabling the anticipation of population increases or recruitment failures that may impact the fishery.

Stock-recruitment (S-R) models are commonly fitted to S-R data with a least-squares method. Errors in modeling are usually assumed to be normal or lognormal, regardless of whether such an assumption is realistic. A Monte Carlo simulation approach was used to evaluate the impact of the assumption of error structure on S-R modeling. The generalized linear model, which can readily deal with different error structures, was used in estimating parameters. This study suggests that the quality of S-R parameter estimation, measured by estimation errors, can be influenced by the realism of error structure assumed in an estimation, the number of S-R data points, and the number of outliers in modeling. A small number of S-R data points and the presence of outliers in S-R data could increase the difficulty in identifying an appropriate error structure in modeling, which might lead to large biases in the S-R parameter estimation. This study shows that generalized linear model methods can help identify an appropriate error distribution in S-R modeling, leading to an improved estimation of parameters even when there are outliers and the number of S-R data points is small. We recommend the generalized linear model be used for quantifying stock-recruitment relationships.

The present research investigates the effects of cash conversion cycle on economic value added among companies listed on Tehran's stock exchange. The sample of study includes 118 companies. The multivariate-regression method has been used for analysis of research hypotheses. Results indicated that a reverse and statistically significant relationship exists between companies' cash conversion cycle and their economic value added. In other words, by reducing the length of cash conversion cycle within reasonable limits, companies are able to increase their economic value added.

Harvest restrictions and stock enhancement are commonly proposed management responses for sustaining degraded fisheries, but comparisons of their relative effectiveness have seldom been considered prior to making policy choices. We built a population model that incorporated both size-dependent harvest restrictions and stock enhancement contributions to explore trade-offs between minimum length limits and stock enhancement for improving population sustainability and fishery metrics (e.g., catch). We used a Murray cod Maccullochella peelii peelii population as a test case, and the model incorporated density-dependent recruitment processes for both hatchery and wild fish. We estimated the spawning potential ratio (SPR) and fishery metrics (e.g., angler catch) across a range of minimum length limits and stocking rates. Model estimates showed that increased minimum length limits were much more effective than stock enhancement for increasing SPR and angler catches in exploited populations, but length limits resulted in reduced harvest. Stocking was predicted to significantly increase total recruitment, population sustainability, and fishery metrics only in systems where natural reproduction had been greatly reduced via habitat loss, fishing mortality was high, or both. If angler fishing effort increased with increased fish abundance from stocking efforts, fishing mortality was predicted to increase and reduce the benefits realized from stocking. The model also indicated that benefits from stock enhancement would be reduced if reproductive efficiency of hatchery-origin fish was compromised. The simulations indicated that stock enhancement was a less effective method to improve fishery sustainability than measures designed to reduce fishing mortality (e.g., length limits).

A comparison between the northwestern Hawaiian islands (NWHI), a large, remote, and lightly fished area, and the main Hawaiian islands (MHI), an urbanized, heavily fished area, revealed dramatic differences in the numerical density, size, and biomass of the shallow reef fish assemblages. Grand mean fish standing stock in the NWHI was more than 260% greater than in the MHI. The most striking difference was the abundance and size of large apex predators (primarily sharks and jacks) in the NWHI compared to the MHI. More than 54% of the total fish biomass in the NWHI consisted of apex predators, whereas this trophic level accounted for less than 3% of the fish biomass in the MHI. In contrast, fish biomass in the MHI was dominated by herbivores (55%) and small-bodied lower-level carnivores (42%). Most of the dominant species by weight in the NWHI were either rare or absent in the MHI and the target species that were present, regardless of trophic level, were nearly always larger in the NWHI. These differences represent both near-extirpation of apex predators and heavy exploitation of lower trophic levels in the MHI compared to the largely unfished NWHI. The reefs in the NWHI are among the few remaining large-scale, intact, predator-dominated reef ecosystems left in the world and offer an opportunity to understand how unaltered ecosystems are structured, how they function, and how they can most effectively be preserved. The differences in fish assemblage structure in this study are evidence of the high level of exploitation in the MHI and the pressing need for ecosystem-level management of reef systems in the MHI as well as the NWHI.

The effects of three forest management alternatives on stand development were simulated using the MOTTI stand simulator, a stand-level analysis tool developed for multiple-purpose forestry planning. The simulation results were used to analyse the effects of different management schedules on wood production, profitability, carbon sequestration and biodiversity. Stand data from a 35-year-old Norway spruce (Picea abies (L.) Karst.) dominated stand with a deciduous admixture were used as the starting point. Stand development was simulated for a period of 35 years, and additionally for 65 years for biodiversity analyses. The three management alternatives were-(1) pure spruce stand: two commercial thinnings with removal of deciduous admixture, regeneration at 70 years, goal to maximize wood production; (2) mixed stand: as the previous one, but the deciduous admixture was maintained throughout the rotation, goal to enhance biodiversity; (3) unmanaged: no treatments.

Results from a vector autoregression show that oil prices and oil price volatility both play important roles in affecting real stock returns. There is evidence that oil price dynamics have changed. After 1986, oil price movements explain a larger fraction of the forecast error variance in real stock returns than do interest rates. There is also evidence that oil price volatility shocks have asymmetric effects on the economy. ᮊ 1999 Elsevier Science B.V. All rights reserved. JEL classifications: Q43; E44 P. Sadorsky 0140-9883r99r$ -see front matter ᮊ 1999 Elsevier Science B.V. All rights reserved. Ž . PII: S 0 1 4 0 -9 8 8 3 9 9 0 0 0 2 0 -1 ( ) P. Sadorsky r Energy Economics 21 1999 449᎐469 450

Biomass fractions (total aboveground, branches and foliage) were estimated from a small footprint discretereturn LiDAR system in an unmanaged Mediterranean forest in central Spain. Several biomass estimation models based on LiDAR height, intensity or height combined with intensity data were explored. Raw intensity data were normalized to a standard range in order to remove the range dependence of the intensity signal. In general terms, intensity-based models provided more accurate predictions of the biomass fractions. Height models selected were mainly based on a percentile of the height distribution. Intensity models selected included variables that consider the percentage of the intensity accumulated at different height percentiles, which implicitly take into account the height distribution. The general models derived considering all species together were based on height combined with intensity data. These models yielded R 2 values greater than 0.58 for the different biomass fractions considered and RMSE values of 28.89, 18.28 and 1.51 Mg ha −1 for aboveground, branch and foliage biomass, respectively. Results greatly improved for species-specific models using the main species present in each plot, with R 2 values greater than 0.85, 0.70 and 0.90 for black pine, Spanish juniper and Holm oak, respectively, and with lower RMSE for the biomass fractions. Reductions in LiDAR point density had only a small effect on the results obtained, except for those models based on a variation of the Canopy Reflection Sum, which was weighted by the mean point density. Based on the species-specific equations derived, Holm oak dominated plots showed the highest average carbon contained by aboveground biomass and branch biomass 44.66 and 31.42 Mg ha − 1 respectively, while for foliage biomass carbon, Spanish juniper showed the highest average value (3.04 Mg ha − 1 ).

The goal of this paper is to examine whether the volatility of the growth in the US oil stocks has changed overtime, and if it has then whether or not this change is real. We find that the growth in volatility of oil stocks has declined overtime. We conduct a Monte Carlo simulation exercise to investigate whether this decline is real or an artefact of the growth definition. Our findings support the fact that the decline in growth volatility of oil stocks is an artefact of the growth definition. This is because a data generating process having a unit root with drift has a tendency to grow and thereby pulls the variance of growth down with time.

Land use/land cover change is an important driver of global change and changes in carbon stocks. Estimating the changes in carbon stocks due to tropical deforestation has been difficult, mainly because of uncertainties in estimating deforestation rates and the biomass in the forest that have been cut. In this study, we combined detailed land-use change over a 27-year period based on satellite images and forest inventory data to estimate changes in biomass carbon stocks in the Xishuangbanna prefecture (1.9 million ha) of China. Xishuangbanna is located in southwestern China in the upper watershed of the Mekong River, and the major forest types are tropical seasonal rain forest, mountain rain forest, and subtropical evergreen broadleaf forest. In the past when the region was completely forested the total biomass carbon would have been approximately 212.65 AE 8.75 Tg C. By 1976 forest cover had been reduced to 70%, and in addition many forests had been degraded resulting in a large decrease in the total biomass carbon stocks (86.97 AE 3.70 Tg C). From 1976 to 2003, the mean deforestation rate was 13 722 ha year À1 (1.12%), and this resulted in the loss of 370,494 ha of forest, and by 2003 total biomass carbon stocks had been reduced to 80.85 AE 2.64 Tg C. The annual carbon emissions due to land-use change, mainly forest conversion to agriculture and rubber plantations, were 0.37 AE 0.03 Tg C year À1 between 1976 and 1988 and 0.13 AE 0.04 Tg C year À1 between 1988 and 2003. During the next 20 years, if rubber plantations expand into forests outside of reserves, shrublands, grasslands, and shifting cultivation below 1500 m the total biomass carbon stocks of Xishuangbanna will decrease to 76.45 AE 1.49 Tg C in 2023. This would reflect a loss of 4.13 AE 1.14 Tg C between 2003 and 2023, or an annual loss of 0.21 AE 0.06 Tg C year À1 . 1. Alternatively, if rubber plantations only expand into areas of shifting cultivation below 1500 m, and all areas presently in shrublands and grasslands are allowed to recover into secondary forests, total biomass carbon stock of the region would increase to 92.65 AE 3.80 Tg C in 2023. Under this scenario, the growth of existing forests and the expansion of new forests would result in a net sequestration of 0.60 AE 0.06 Tg C year À1 . This study demonstrates that the uncertainty of biomass estimates can be greatly reduced if detailed land-use analyses are combined with forest inventory data, and that slight changes in future land-use practices can have large implications for carbon fluxes. # 2007 Published by Elsevier B.V.