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Unit Values (unit + value)
Selected AbstractsQuantity versus quality effects of generic advertising: The case of Norwegian salmonAGRIBUSINESS : AN INTERNATIONAL JOURNAL, Issue 1 2007Řystein Myrland In this article, a two-equation sample selection model is used to estimate a household demand function for salmon incorporating domestic generic advertising. The two-equation estimation procedure, based on purchase and unit value equations, allows us to handle heavily censored panel data for salmon purchases by Norwegian households and the quality effects simultaneously. Unit values of the aggregated salmon commodity calculated from the observed expenditures and quantities are hypothesized to represent the average quality of the purchased commodity. Advertising effects on both purchases and unit values are investigated. The model also allows us to separate the effects of conditional purchases and purchase probabilities. Results indicate that most (76%) of the advertising effect is through the change of nonpurchase occasions to purchase occasions, and that generic salmon advertising induces Norwegian households to spend more money on salmon. However, advertising causes households to select more expensive products rather than increasing their purchased quantities. [EconLit citations: D12, C24]. © 2007 Wiley Periodicals, Inc. Agribusiness 23: 85,100, 2007. [source] Injecting 1000 Centistoke Liquid Silicone With Ease and PrecisionDERMATOLOGIC SURGERY, Issue 3 2003Anthony V. Benedetto DO, FACP BACKGROUND Since the Food and Drug Administration approved the use of the 1000 centistoke liquid silicone, Silikon 1000, for intraocular injection, the off-label use of this injectable silicone oil as a permanent soft-tissue filler for facial rejuvenation has increased in the United States. Injecting liquid silicone by the microdroplet technique is the most important preventive measure that one can use to avoid the adverse sequelae of silicone migration and granuloma formation, especially when injecting silicone to improve small facial defects resulting from acne scars, surgical procedures, or photoaging. OBJECTIVE To introduce an easy method for injecting a viscous silicone oil by the microdroplet technique, using an inexpensive syringe and needle that currently is available from distributors of medical supplies in the United States. METHOD We suggest the use of a Becton Dickinson 3/10 cc insulin U-100 syringe to inject Silikon 1000. This syringe contains up to 0.3 mL of fluid, and its barrel is clearly marked with an easy-to-read scale of large cross-hatches. Each cross-hatch marking represents either a unit value of 0.01 mL or a half-unit value of 0.005 mL of fluid, which is the approximate volume preferred when injecting liquid silicone into facial defects. Because not enough negative pressure can be generated in this needle and syringe to draw up the viscous silicone oil, we describe a convenient and easy method for filling this 3/10 cc diabetic syringe with Silikon 1000. RESULTS We have found that by using the Becton Dickinson 3/10 cc insulin U-100 syringe, our technique of injecting minute amounts of Silikon 1000 is facilitated because each widely spaced cross-hatch on the side of the syringe barrel is easy to read and measures exact amounts of the silicone oil. These lines of the scale on the syringe barrel are so large and clearly marked that it is virtually impossible to overinject the most minute amount of silicone. CONCLUSION Sequential microdroplets of 0.01 cc or less of Silikon 1000 can be measured and injected with the greatest ease and precision so that inadvertent overdosing and complications can be avoided. [source] Numerical investigation of the reliability of a posteriori error estimation for advection,diffusion equationsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 9 2008A. H. ElSheikh Abstract A numerical investigation of the reliability of a posteriori error estimation for advection,diffusion equations is presented. The estimator used is based on the solution of local problems subjected to Neumann boundary conditions. The estimated errors are calculated in a weighted energy norm, a stability norm and an approximate fractional order norm in order to study the effect of the error norm on both the effectivity index of the estimated errors and the mesh adaptivity process. The reported numerical results are in general better than what is available in the literature. The results reveal that the reliability of the estimated errors depends on the relation between the mesh size and the size of local features in the solution. The stability norm is found to have some advantages over the weighted energy norm in terms of producing effectivity indices closer to the optimal unit value, especially for problems with internal sharp layers. Meshes adapted by the element residual method measured in the stability norm conform to the sharp layers and are shown to be less dependent on the wind direction. Copyright © 2007 John Wiley & Sons, Ltd. [source] Black's Model of Interest Rates as Options, Eigenfunction Expansions and Japanese Interest RatesMATHEMATICAL FINANCE, Issue 1 2004Viatcheslav Gorovoi Black's (1995) model of interest rates as options assumes that there is a shadow instantaneous interest rate that can become negative, while the nominal instantaneous interest rate is a positive part of the shadow rate due to the option to convert to currency. As a result of this currency option, all term rates are strictly positive. A similar model was independently discussed by Rogers (1995). When the shadow rate is modeled as a diffusion, we interpret the zero-coupon bond as a Laplace transform of the area functional of the underlying shadow rate diffusion (evaluated at the unit value of the transform parameter). Using the method of eigenfunction expansions, we derive analytical solutions for zero-coupon bonds and bond options under the Vasicek and shifted CIR processes for the shadow rate. This class of models can be used to model low interest rate regimes. As an illustration, we calibrate the model with the Vasicek shadow rate to the Japanese Government Bond data and show that the model provides an excellent fit to the Japanese term structure. The current implied value of the instantaneous shadow rate in Japan is negative. [source] THE EFFECTS OF ITQ IMPLEMENTATION: A DYNAMIC APPROACHNATURAL RESOURCE MODELING, Issue 4 2000LEE G. ANDERSON ABSTRACT. This paper investigates the intertemporal effects of introducing Individual Transferable Quota, ITQ, fishery management programs on stock size, fleet size and composition, and returns to quota holders and to vessel operators. Theoretical analysis is conducted using a specific version of a general dynamic model of a regulated fishery. It is demonstrated that the effects will differ depending upon the prevailing regulation program, current stock size, and existing fleet size, composition and mobility and upon how the stock and fleet change over time after the switch to ITQs. The paper expands upon previous works by modeling the dynamics of change in fleet and stock size and by allowing for changes in the TAC as stock size changes, by comparing ITQs to different regulations, and by allowing the status quo before ITQ implementation to be something other than a bioeconomic equilibrium. Specific cases are analyzed using a simulation model. The analysis shows that the annual return per unit harvest to quota owners can increase or decrease over the transition period due to counteracting effects of changes in stock and fleet size. With ITQs denominated as a percentage of the TAC, the current annual value of a quota share depends upon the annual return per unit of harvest and the annual amount of harvest rights. Because the per unit value can increase or decrease over time, it is also possible that the total value can do the same. Distribution effects are also studied and it is shown that while the gains from quota share received are the present value of a potentially infinite stream of returns, potential losses are the present value of a finite stream, the length of which depends upon the remaining life of the vessel and the expected time it will continue to operate. [source] Dynamics of petroleum markets in OECD countries in a monthly VAR,VEC model (1995,2007)OPEC ENERGY REVIEW, Issue 1 2008Mehdi Asali This paper contains some results of a study in which the dynamics of petroleum markets in the Organization for Economic Cooperation and Development (OECD) is investigated through a vector auto regression (VAR),vector error correction model. The time series of the model comprises the monthly data for the variables demand for oil in the OECD, WTI in real term as a benchmark oil price, industrial production in OECD as a proxy for income and commercial stocks of crude oil and oil products in OECD for the time period of January 1995 to September 2007. The detailed results of this empirical research are presented in different sections of the paper; nevertheless, the general result that emerges from this study could be summarised as follows: (i) there is convincing evidence of the series being non-stationary and integrated of order one I(1) with clear signs of co-integration relations between the series; (ii) the VAR system of the empirical study appears stable and restores its dynamics as usual, following a shock to the rate of changes of different variables of the model, taking between five and eight periods (months in our case); (iii) we find the lag length of 2 as being optimal for the estimated VAR model; (iv) significant impact of changes in the commercial crude and products' inventory level on oil price and on demand for oil is highlighted in our empirical study and in different formulations of the VAR model, indicating the importance of the changes in the stocks' level on oil market dynamics; and (v) income elasticity of deman for oil appears to be prominent and statistically significant in most estimated models of the VAR system in the long run, while price elasticity of demand for oil is found to be negligible and insignificant in the short run. However, while aggregate oil consumption does not appear to be very sensitive to the changes of oil prices (which is believed to be because of the so-called ,rebound effect' of oil (energy) efficiency in the macro level) in the macro level, the declining trend of oil intensity (oil used for production of unit value of goods and services), particularly when there is an upward trend in oil price, clearly indicates the channels through which persistent changes in oil prices could affect the demand for oil in OECD countries. [source] An analysis of refractometry as a method of determining blood total protein concentration in the American lobster Homarus americanus (Milne Edwards)AQUACULTURE RESEARCH, Issue 8 2002G Ozbay Abstract Given the high unit value of live American lobsters (Homarus americanus), a non-destructive field method to assess physiological state is desirable during out-of-water transport conditions. This study compared an Uricon® specific gravity refractometer, with a commercial veterinary blood analyser (Vet-Test), as a method for determining the blood total protein concentration in live, out-of-water individuals. Regression analysis of R2 = 0.8641 (n = 64) was observed in determination of blood total protein concentration, y = 0.0036x + 1.0163 where x is the protein concentration in mg dL,1 in Vet-Test. Our results (R2 = 0.864, SE ± 0.003) support the results (R2 = 0.985) of the previous study conducted by Leavitt & Bayer (1977) in which serum total protein was compared with the refractometric method. We therefore confirm that the refractometric method can be used as a reliable method to indicate health of a lobster by measuring the blood total protein concentration. The results show good correlation between the protein concentrations observed using the refractometric method and a Vet-Test blood chemistry analyser. anova analysis was significant between the protein refractometer and the Vet-Test (P < 0.05). Although protein concentration units obtained from both methods were different the results followed the same trends. Refractometry as a method is reliable to determine blood total protein concentrations in the American lobster. Consequently, a refractometric method can be used directly by commercial growers and distributors to assess responses to holding facility conditions and to feeding regimes. Whole blood protein concentrations may provide more information than serum protein concentrations as measured in the study of Leavitt & Bayer (1977). [source] Specialization across varieties and North,South competitionECONOMIC POLICY, Issue 53 2008Lionel Fontagné SUMMARY North,South competition quality Analyzing a new database that makes it possible to disaggregate trade flows across many countries according to unit values, we show that international specialization in terms of quality within industries and product categories plays an important role in the dynamics of North,South competition. The different specialization of countries at different levels of development within products and across varieties is mirrored in the recent shifts in world market shares, which are very different across quality segments: the South is not gaining market share in high-value portions of trade pattern. In this respect Europe's specialization pattern appears to be different from that of the US and Japan, and may allow it to better resist the competitive pressure of the South. , Lionel Fontagné, Guillaume Gaulier and Soledad Zignago [source] Improved sample preparation method for glycan analysis of glycoproteins by CE-LIF and CE-MSELECTROPHORESIS, Issue 8 2010Zoltan Szabo Abstract CE is a high-resolution separation technique broadly used in the biotechnology industry for carbohydrate analysis. The standard sample preparation protocol for CE analysis of glycans released from glycoproteins generally requires derivatization times of overnight at 37°C, using ,100 fold excess of fluorophore reagent, 8-aminopyrene-1,3,6-trisulfonic-acid, if the sample is unknown, or it is a regulated biotherapeutic product, possibly containing terminal sialic acid(s). In this paper, we report on significant improvements for the standard CE sample preparation method of glycan analysis. By replacing the conventionally used acetic acid catalyst with citric acid, as low as 1:10 glycan to fluorophore molar ratio (versus the typical 1:,100 ratio) maintained the >95% derivatization yield at 55°C with only 50,min reaction time. Terminal sialic acid loss was negligible at 55°C during the derivatization process, and indicating that the kinetics of labeling at 55°C was faster than the loss of sialic acid from the glycan. The reduced relative level of 8-aminopyrene-1,3,6-trisulfonic-acid simplified the removal of excess reagent, important in both CE-LIF (electrokinetic injection bias) and CE-MS (ion suppression). Coupling CE- ESI-MS confirmed that the individual peaks separated by CE corresponded to single glycans and increased the confidence of structural assignment based on glucose unit values. [source] Biogeography of the marine actinomycete SalinisporaENVIRONMENTAL MICROBIOLOGY, Issue 11 2006Paul R. Jensen Summary Marine actinomycetes belonging to the genus Salinispora were cultured from marine sediments collected at six geographically distinct locations. Detailed phylogenetic analyses of both 16S rRNA and gyrB gene sequences reveal that this genus is comprised of three distinct but closely related clades corresponding to the species Salinispora tropica, Salinispora arenicola and a third species for which the name ,Salinispora pacifica' is proposed. Salinispora arenicola was cultured from all locations sampled and provides clear evidence for the cosmopolitan distribution of an individual bacterial species. The co-occurrence of S. arenicola with S. tropica and S. pacifica suggests that ecological differentiation as opposed to geographical isolation is driving speciation within the genus. All Salinispora strains cultured to date share greater than 99% 16S rRNA gene sequence identity and thus comprise what has been described as a microdiverse ribotype cluster. The description of this cluster as a new genus, containing multiple species, provides clear evidence that fine-scale 16S rDNA sequence analysis can be used to delineate among closely related species and that more conservative operational taxonomic unit values may significantly underestimate global species diversity. [source] The net barter terms of trade: A smooth transition approachINTERNATIONAL JOURNAL OF FINANCE & ECONOMICS, Issue 1 2003Anna Persson Abstract This paper analyses the net barter terms of trade measured by the primary commodity price index relative to the indexes of unit values of export of manufactures from industrial countries. The starting point is that the series is stationary but possibly non-linear. Statistical tests indicate that the logarithmed series is non-linear and we estimate a Smooth Transition Autoregressive model to describe the process. The dynamics of the model are illustrated by use of parametrically estimated local spectra and generalized impulse response functions. Our model encompasses models from several previous studies, and our conclusion is that the starting point very much decides the outcome. Copyright © 2003 John Wiley & Sons, Ltd. [source] Quantity versus quality effects of generic advertising: The case of Norwegian salmonAGRIBUSINESS : AN INTERNATIONAL JOURNAL, Issue 1 2007Řystein Myrland In this article, a two-equation sample selection model is used to estimate a household demand function for salmon incorporating domestic generic advertising. The two-equation estimation procedure, based on purchase and unit value equations, allows us to handle heavily censored panel data for salmon purchases by Norwegian households and the quality effects simultaneously. Unit values of the aggregated salmon commodity calculated from the observed expenditures and quantities are hypothesized to represent the average quality of the purchased commodity. Advertising effects on both purchases and unit values are investigated. The model also allows us to separate the effects of conditional purchases and purchase probabilities. Results indicate that most (76%) of the advertising effect is through the change of nonpurchase occasions to purchase occasions, and that generic salmon advertising induces Norwegian households to spend more money on salmon. However, advertising causes households to select more expensive products rather than increasing their purchased quantities. [EconLit citations: D12, C24]. © 2007 Wiley Periodicals, Inc. Agribusiness 23: 85,100, 2007. [source] Food trade balances and unit values: What can they reveal about price competition?AGRIBUSINESS : AN INTERNATIONAL JOURNAL, Issue 1 2002Mark J. Gehlhar Price competition is a fundamental assumption in modeling trade. Empirical applications often use unit values as proxies for price. This is a problem if unit values cannot explain trade flows consistent with the price competition assumption. The paper determines whether this condition exists in food product trade. Trade balances by product are used to indicate successful competition in trade. Export and import unit values are used to determine if competition is dominated by price or nonprice competition. Trade flows are then categorized in four ways: successful price competition, unsuccessful price competition, successful nonprice competition, and unsuccessful nonprice competition. This categorization is applied to 372 food products using the Standard International Trade Classification. Nearly 40% of U.S. food exports could be characterized as dominated by nonprice competition. In those instances, we contend that unit values are not valid proxies for price, thereby limiting their usefulness in traditional import demand estimation and trade policy simulation models. © 2002 Wiley Periodicals, Inc. [source] Dimensions of quality upgradingTHE ECONOMICS OF TRANSITION, Issue 1 2005Evidence from CEECs Abstract The impact of the Central and Eastern European (CEE) economies' trade integration with European markets on CEE trade structures has been studied extensively. These studies frequently observe a quality upgrading of CEE exports. In this paper we consider three dimensions of quality upgrading: upgrading across industries, upgrading across different quality segments within industries and, finally, product upgrading within quality segments inside industries. For the analysis we partition industries into quality segments based on EU-15 import unit values. The results for ten CEE countries (comprising the CEE-5, the Baltics and South East Europe) and thirteen industries suggest fundamental differences, both across country groups and across the three different notions of quality upgrading. The CEE-5 show no evidence of entering a ,low-quality trap' in all three dimensions. By contrast, while there is a general catching-up process across industries and inside quality segments, the second notion of low-quality specialization may be applicable within the high-tech industries to the performance for the Baltics and South East Europe as a group. [source] Hedonic Price Indexes and the Matched Models ApproachTHE MANCHESTER SCHOOL, Issue 1 2004Mick Silver We consider three approaches to estimating quality-adjusted price changes: (i) the dummy variable approach from a hedonic regression, (ii) a superlative or exact hedonic index and (iii) a matching technique,a technique akin to that used by statistical offices. The dummy variable approach is prevalent in the literature and has been used for independent estimates of quality changes when commenting on sources of error in consumer price indexes. However, the availability of scanner data provides an opportunity to utilize data on the prices (unit values), volumes and quality characteristics of a much wider range of transactions and to consider methods less restrictive than the dummy variable approach. The practical use of superlative or exact hedonic index and matching techniques using scanner data is explored, and the results from all three methods are compared. A feature of the paper is the breadth of the empirical work. It not only encompasses three different approaches, but extends across four different types of consumer durables. The manner in which the three approaches relate to each other is explored and the implications for quality-adjusted price changes is discussed. [source] | |||||||||||||