61 research outputs found

    Hedonic Valuation of Sportfishing Harvest

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    A hedonic valuation strategy is introduced to estimate the marginal value of sportfishing harvest. The strategy uses market prices, thereby avoiding some of the measurement problems associated with the constructed or proxy prices used in common valuation methods. A charter fee hedonic equation is estimated using data from the market for offshore charter fishing in the Gulf of Mexico. The marginal value of sportfishing harvest is identified using spatial variation in harvest rates and fish sizes. A two-stage minimum distance estimator is used to address potential omitted variables and cluster-sampling issues. Our results demonstrate that valid estimates of the marginal value of sportfishing harvest can be derived directly using market prices. The estimated marginal value per fish is consistent with published estimates using alternative methods. Thus, the hedonic approach suggested in this article offers promise as an independent validation of the typical methods used to value sportfishing harvest.Sportfishing, charter boats, hedonic, revealed preference, valuation, Public Economics, Research Methods/ Statistical Methods, Q22, Q26, Q51,


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    This paper combines a model of open access fisheries exploitation with a distance-based approach to missing labor and product markets. The model generates predictions about the circumstances under which exploitation increases or decreases with distance. An econometric model is estimated with survey data from artisanal fishing households in Minahasa, Indonesia. The results can be used to assess the impacts of improved transportation infrastructure on fishery exploitation.Marketing,

    Migration and Fishing in Indonesian Coastal Villages

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    The Annual Economic Survey of Federal Gulf Shrimp Permit Holders: Report on the Design, Implementation, and Descriptive Results for 2006

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    This technical memorandum documents the design, implementation, data preparation, and descriptive results for the 2006 Annual Economic Survey of Federal Gulf Shrimp Permit Holders. The data collection was designed by the NOAA Fisheries Southeast Fisheries Science Center Social Science Research Group to track the financial and economic status and performance by vessels holding a federal moratorium permit for harvesting shrimp in the Gulf of Mexico. A two page, self-administered mail survey collected total annual costs broken out into seven categories and auxiliary economic data. In May 2007, 580 vessels were randomly selected, stratified by state, from a preliminary population of 1,709 vessels with federal permits to shrimp in offshore waters of the Gulf of Mexico. The survey was implemented during the rest of 2007. After many reminder and verification phone calls, 509 surveys were deemed complete, for an ineligibility-adjusted response rate of 90.7%. The linking of each individual vessel’s cost data to its revenue data from a different data collection was imperfect, and hence the final number of observations used in the analyses is 484. Based on various measures and tests of validity throughout the technical memorandum, the quality of the data is high. The results are presented in a standardized table format, linking vessel characteristics and operations to simple balance sheet, cash flow, and income statements. In the text, results are discussed for the total fleet, the Gulf shrimp fleet, the active Gulf shrimp fleet, and the inactive Gulf shrimp fleet. Additional results for shrimp vessels grouped by state, by vessel characteristics, by landings volume, and by ownership structure are available in the appendices. The general conclusion of this report is that the financial and economic situation is bleak for the average vessels in most of the categories that were evaluated. With few exceptions, cash flow for the average vessel is positive while the net revenue from operations and the “profit” are negative. With negative net revenue from operations, the economic return for average shrimp vessels is less than zero. Only with the help of government payments does the average owner just about break even. In the short-term, this will discourage any new investments in the industry. The financial situation in 2006, especially if it endures over multiple years, also is economically unsustainable for the average established business. Vessels in the active and inactive Gulf shrimp fleet are, on average, 69 feet long, weigh 105 gross tons, are powered by 505 hp motor(s), and are 23 years old. Three-quarters of the vessels have steel hulls and 59% use a freezer for refrigeration. The average market value of these vessels was 175,149in2006,aboutahundredthousanddollarslessthantheaverageoriginalpurchaseprice.Theoutstandingloansaveraged175,149 in 2006, about a hundred-thousand dollars less than the average original purchase price. The outstanding loans averaged 91,955, leading to an average owner equity of 83,194.Basedonthesample,85owneroperated.Onaverage,thesevesselsburned52,931gallonsoffuel,landed101,268poundsofshrimp,andreceived83,194. Based on the sample, 85% of the federally permitted Gulf shrimp fleet was actively shrimping in 2006. Of these 386 active Gulf shrimp vessels, just under half (46%) were owner-operated. On average, these vessels burned 52,931 gallons of fuel, landed 101,268 pounds of shrimp, and received 2.47 per pound of shrimp. Non-shrimp landings added less than 1% to cash flow, indicating that the federal Gulf shrimp fishery is very specialized. The average total cash outflow was 243,415ofwhich243,415 of which 108,775 was due to fuel expenses alone. The expenses for hired crew and captains were on average 54,866whichindicatestheimportanceoftheindustryasasourceofwageincome.Theresultingaveragenetcashflowis54,866 which indicates the importance of the industry as a source of wage income. The resulting average net cash flow is 16,225 but has a large standard deviation. For the population of active Gulf shrimp vessels we can state with 95% certainty that the average net cash flow was between 9,500and9,500 and 23,000 in 2006. The median net cash flow was 11,843.BasedontheincomestatementforactiveGulfshrimpvessels,theaveragefixedcostsaccountedforjustunderaquarterofoperatingexpenses(23.1Theaveragelaborcontribution(ascaptain)ofanowneroperatorisestimatedatabout11,843. Based on the income statement for active Gulf shrimp vessels, the average fixed costs accounted for just under a quarter of operating expenses (23.1%), labor costs for just over a quarter (25.3%), and the non-labor variable costs for just over half (51.6%). The fuel costs alone accounted for 42.9% of total operating expenses in 2006. It should be noted that the labor cost category in the income statement includes both the actual cash payments to hired labor and an estimate of the opportunity cost of owner-operators’ time spent as captain. The average labor contribution (as captain) of an owner-operator is estimated at about 19,800. The average net revenue from operations is negative 7,429,andisstatisticallydifferentandlessthanzeroinspiteofalargestandarddeviation.TheeconomicreturntoGulfshrimpingisnegative47,429, and is statistically different and less than zero in spite of a large standard deviation. The economic return to Gulf shrimping is negative 4%. Including non-operating activities, foremost an average government payment of 13,662, leads to an average loss before taxes of 907forthevesselowners.Theconfidenceintervalofthisvaluestraddleszero,sowecannotreject,with95TheaverageinactiveGulfshrimpvesselisgenerallyofasmallerscalethantheaverageactivevessel.Inactivevesselsarephysicallysmaller,arevaluedmuchlower,andarelessdependentonloans.Fixedcostsaccountfornearlythreequartersofthetotaloperatingexpensesof907 for the vessel owners. The confidence interval of this value straddles zero, so we cannot reject, with 95% certainty, that the population average is zero. The average inactive Gulf shrimp vessel is generally of a smaller scale than the average active vessel. Inactive vessels are physically smaller, are valued much lower, and are less dependent on loans. Fixed costs account for nearly three quarters of the total operating expenses of 11,926, and only 6% of these vessels have hull insurance. With an average net cash flow of negative 7,537,theinactiveGulfshrimpfleethasamajorliquidityproblem.Onaverage,netrevenuefromoperationsisnegative7,537, the inactive Gulf shrimp fleet has a major liquidity problem. On average, net revenue from operations is negative 11,396, which amounts to a negative 15% economic return, and owners lose 9,381ontheirvesselsbeforetaxes.Tosustainsuchlossesandespeciallytosurvivethenegativecashflow,manyoftheownersmustbesubsidizingtheirshrimpvesselswiththehelpofotherincomeorwealthsourcesoraredrawingdowntheirequity.ActiveGulfshrimpvesselsinallstatesbutTexasexhibitednegativereturns.TheAlabamaandMississippifleetshavethehighestassets(vesselvalues),onaverage,yettheygeneratezerocashflowandnegative9,381 on their vessels before taxes. To sustain such losses and especially to survive the negative cash flow, many of the owners must be subsidizing their shrimp vessels with the help of other income or wealth sources or are drawing down their equity. Active Gulf shrimp vessels in all states but Texas exhibited negative returns. The Alabama and Mississippi fleets have the highest assets (vessel values), on average, yet they generate zero cash flow and negative 32,224 net revenue from operations. Due to their high (loan) leverage ratio the negative 11% economic return is amplified into a negative 21% return on equity. In contrast, for Texas vessels, which actually have the highest leverage ratio among the states, a 1% economic return is amplified into a 13% return on equity. From a financial perspective, the average Florida and Louisiana vessels conform roughly to the overall average of the active Gulf shrimp fleet. It should be noted that these results are averages and hence hide the variation that clearly exists within all fleets and all categories. Although the financial situation for the average vessel is bleak, some vessels are profitable. (PDF contains 101 pages

    Markarian 421's Unusual Satellite Galaxy

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    We present Hubble Space Telescope (HST) imagery and photometry of the active galaxy Markarian 421 and its companion galaxy 14 arcsec to the ENE. The HST images indicate that the companion is a morphological spiral rather than elliptical as previous ground--based imaging has concluded. The companion has a bright, compact nucleus, appearing unresolved in the HST images. This is suggestive of Seyfert activity, or possibly a highly luminous compact star cluster. We also report the results of high dynamic range long-slit spectroscopy with the slit placed to extend across both galaxies and nuclei. We detect no emission lines in the companion nucleus, though there is evidence for recent star formation. Velocities derived from a number of absorption lines visible in both galaxies indicate that the two systems are probably tidally bound and thus in close physical proximity. Using the measured relative velocities, we derive a lower limit on the MKN 421 mass within the companion orbit (R \sim 10 kpc) of 5.9 \times 10^{11} solar masses, and a mass-to-light ratio of >= 17. Our spectroscopy also shows for the first time the presence of H\alpha and [NII] emission lines from the nucleus of MKN 421, providing another example of the appearance of new emission features in the previously featureless spectrum of a classical BL Lac object. We see both broad and narrow line emission, with a velocity dispersion of several thousand km s^{-1} evident in the broad lines.Comment: LaTeX (aaspp4 style), 28 pages, 8 figures, to appear in AJ. Revised text from ref. comments; new & modified figures; new photometry included; minor corrections of typos. Color version of Fig. 1 to appear in Feb. 2000 Sky & Telescop

    Methodological problem with comparing increases in different measures of body weight

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    <p>Abstract</p> <p>Background</p> <p>A number of studies have compared proportional increases over time in waist circumference (WC) and body mass index (BMI). However this method is flawed. Here, we explain why comparisons of WC and BMI must take into account the relationship between them. We used data from two cross-sectional US surveys (NHANES 1988-94 and 2005-06), and calculated the percentage change in the average BMI and the average WC between the two surveys, comparing the results with a regression analysis of changes in WC relative to BMI.</p> <p>Findings</p> <p>The crude percentage change in BMI (5.8%) was marginally greater than for WC (5.1%). But these percentages cannot be directly compared, as the relationship between the measures is described by a regression equation with an intercept term that does not equal zero. The coefficient of time from the regression equation will determine whether or not WC is on average larger for a given BMI at the second compared with the first time point.</p> <p>Conclusion</p> <p>Differences in the percentage change in WC and the percentage change in BMI cannot be usefully directly compared. Comparisons of increases in the two measures must account for the relationship between them as described by the regression equation.</p

    The Arecibo Legacy Fast ALFA Survey: II. Results of Precursor Observations

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    In preparation for the full Arecibo Legacy Fast ALFA extragalactic HI survey, precursor observations were carried out in Aug--Sep 2004 with the 7-beam Arecibo L-band feed array (ALFA) receiver system and the WAPP spectral processors. While these observations were geared mainly at testing and debugging survey strategy, hardware and software, approximately 36 hours of telescope time yielded science--quality data. From those observations, an initial list of 730 tentative detections of varying degree of reliability was extracted. Ninety--eight high signal-to-noise candidates were deemed to be bona fide HI line detections. To test our ability to discriminate cosmic signals from RFI and noise, 165 candidates ranging in reliability likelihood were re--observed with the single beam L--band wide system at Arecibo in Jan--Feb 2005. Of those, 41% were confirmed as real. We present the results of both the ALFA and single beam observations for the sample of 166 confirmed HI sources, as well as our assessment of their optical counterparts. Of the 166 sources, 62 coincide with previously known HI sources, while optical redshifts were available for an additional 18 galaxies; thus, 52% of the redshifts reported here were previously unknown. Of the 166 HI detections, 115 are identified with previously cataloged galaxies, of either known or unknown redshift, leaving 51 objects identified for the first time. Because of the higher sensitivity of the Arecibo system, fewer than 10% of the 166 HI sources would have been detected by a HIPASS--like survey of the same region. Three of the objects have HI masses less than 10^7 solar masses. The full ALFALFA survey which commenced in February 2005 should detect more than 100 times as many objects of similarly low HI mass over the next 5 years.Comment: 40 pages, including 4 tables and 8 figures; to appear in Astron. J.; see http://egg.astro.cornell.edu/alfalfa/pubs.ph

    Higher Doses of Subcutaneous IgG Reduce Resource Utilization in Patients with Primary Immunodeficiency

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    The recommended dose of IgG in primary immunodeficiency (PID) has been increasing since its first use. This study aimed to determine if higher subcutaneous IgG doses resulted in improved patient outcomes by comparing results from two parallel clinical studies with similar design. One patient cohort received subcutaneous IgG doses that were 1.5 times higher than their previous intravenous doses (mean 213 mg/kg/week), whereas the other cohort received doses identical to previous subcutaneous or intravenous doses (mean 120 mg/kg/week). While neither cohort had any serious infections, the cohort maintained on higher mean IgG dose had significantly lower rates of non-serious infections (2.76 vs. 5.18 episodes/year, P < 0.0001), hospitalization (0.20 vs. 3.48 days/year, P < 0.0001), antibiotic use (48.50 vs. 72.75 days/year, P < 0.001), and missed work/school activity (2.10 vs. 8.00 days/year, P < 0.001). The higher-dose cohort had lower health care utilization and improved indices of well being compared to the cohort treated with traditional IgG doses