Terms Of Rewards Research Articles

Barriers to conducting clinical research in reproductive medicine: United States of America

A decrease in National Institute of Health funding and an increase regulations are significant barriers in conducting research in the United States of America.

Crawlability metrics for automated web testing

Web applications are exposed to frequent changes both in requirements and involved technologies. At the same time, there is a continuously growing demand for quality and trust and such a fast evolution and quality constraints claim for mechanisms and techniques for automated testing. Web application automated testing often involves random crawlers to navigate the application under test and automatically explore its structure. However, owing to the specific challenges of the modern Web systems, automatic crawlers may leave large portions of the application unexplored. In this paper, we propose the use of structural metrics to predict whether an automatic crawler with given crawling capabilities will be sufficient or not to achieve high coverage of the application under test. In this work, we define a taxonomy of such capabilities and we determine which combination of them is expected to give the highest reward in terms of coverage increase. Our proposal is supported by an experiment in which 19 web applications have been analyzed.

Subjective neuronal coding of reward: temporal value discounting and risk

A key question in the neurobiology of reward relates to the nature of coding. Rewards are objects that are advantageous or necessary for the survival of individuals in a variety of environmental situations. Thus reward appears to depend on the individual and its environment. The question arises whether neuronal systems in humans and monkeys code reward in subjective terms, objective terms or both. The present review addresses this issue by dealing with two important reward processes, namely the individual discounting of reward value across temporal delays, and the processing of information about risky rewards that depends on individual risk attitudes. The subjective value of rewards decreases with the temporal distance to the reward. In experiments using neurophysiology and brain imaging, dopamine neurons and striatal systems discount reward value across temporal delays of a few seconds, despite unchanged objective reward value, suggesting subjective value coding. The subjective values of risky outcomes depend on the risk attitude of individual decision makers; these values decrease for risk-avoiders and increase for risk-seekers. The signal for risk and the signal for the value of risky reward covary with individual risk attitudes in regions of the human prefrontal cortex, suggesting subjective rather than objective coding of risk and risky value. These data demonstrate that important parameters of reward are coded in a subjective manner in key reward structures of the brain. However, these data do not rule out that other neurons or brain structures may code reward according to its objective value and risk.

Does sward height affect feeding patch choice and voluntary intake in horses?

The numbers of horses grazing at pasture are increasing in developed countries, so a proper understanding of their feeding selectivity and of the tactics they use for extracting nutrients from swards is essential for the management of horses and grasslands. Resource acquisition in herbivores can be optimised through the modulation of their intake and patch selection, both being strongly dependent on the characteristics of swards. However, the principles by which horses adjust their grazing behaviour in response to variations in sward features are not completely understood. The aim of this study was to determine whether the behaviour of horses conforms to optimal foraging models. We hypothesized that, faced with binary choices between vegetative swards of a good and similar quality at three different heights, horses would select the taller sward, i.e. that allowing a higher reward in terms of dry matter intake rate. Three groups of three 2-year-old saddle horses were grazed on a semi-natural pasture that was managed to produce three contrasting sward heights at 6, 11 and 17 cm, in a Latin-square design. The instantaneous intake rate was determined from bite rate measured at pasture on the three sward heights, and bite mass estimated from measurements using swards offered indoors in experimental trays. Daily dry matter intake was estimated individually by total faecal collection and an estimation of digestibility from faecal nitrogen. Short-term (first 30 min) and daily preferences were assessed from the time spent grazing each sward offered in pair-wise tests at pasture. The results show that daily voluntary intake (an average of 21 g DM kg LW −1 day −1) and total grazing time (an average of 14 h day −1) were independent of sward height and of the choice of patches offered. In choice situations, the animals spent more time grazing on the taller sward, both during the first 30 min and at the daily scale. These results show that horses choose between vegetative patches of a good and similar quality according to the predictions from optimal foraging models, and select the one that they can ingest faster. Further research will now have to explore how the horses will adapt their feeding behaviour when they face a trade-off between sward height and quality.

Evidence for counting in insects

Here we investigate the counting ability in honeybees by training them to receive a food reward after they have passed a specific number of landmarks. The distance to the food reward is varied frequently and randomly, whilst keeping the number of intervening landmarks constant. Thus, the bees cannot identify the food reward in terms of its distance from the hive. We find that bees can count up to four objects, when they are encountered sequentially during flight. Furthermore, bees trained in this way are able count novel objects, which they have never previously encountered, thus demonstrating that they are capable of object-independent counting. A further experiment reveals that the counting ability that the bees display in our experiments is primarily sequential in nature. It appears that bees can navigate to food sources by maintaining a running count of prominent landmarks that are passed en route, provided this number does not exceed four.

Beating Earnings Benchmarks and the Cost of Debt

Prior research documents that firms tend to beat three earnings benchmarks—zero earnings, last year's earnings, and analyst's forecasted earnings—and that there are both equity market and compensation-related benefits associated with beating these benchmarks. This study investigates whether and under what conditions beating these three earnings benchmarks reduces a firm's cost of debt. I use two proxies for a firm's cost of debt: credit ratings and initial bond yield spread. Results suggest that firms beating earnings benchmarks have a higher probability of rating upgrades and a smaller initial bond yield spread. Additional analyses indicate that (1) the benefits of beating earnings benchmarks are more pronounced for firms with high default risk; (2) beating the zero earnings benchmark generally provides the biggest reward in terms of a lower cost of debt; and (3) the reduction in the cost of debt is attenuated but does not disappear for firms beating benchmarks through earnings management. In sum, results suggest that there are benefits associated with beating earnings benchmarks in the debt market. These benefits vary by benchmark, firm default risk, and method utilized to beat the benchmark. Among other implications, this evidence suggests that the relative importance of specific benchmarks differs across the equity and bond markets.

Beating Earnings Benchmarks and the Cost of Debt

Prior research documents that firms tend to beat three earnings benchmarks: zero earnings, last year's earnings, and analyst's forecasted earnings, and that there are both equity market and compensation-related benefits associated with beating these benchmarks. This study investigates whether and under what conditions beating these three earnings benchmarks reduces a firm's cost of debt. I use two proxies for a firm's cost of debt: credit ratings and initial bond yield spread. Results suggest that firms beating earnings benchmarks have a higher probability of rating upgrades and a smaller initial bond yield spread. Additional analyses indicate that (i) the benefits of beating earnings benchmarks are more pronounced for firms with high default risk; (ii) beating the zero earnings benchmark generally provides the biggest reward in terms of a lower cost of debt; and (iii) the reduction in the cost of debt is attenuated but does not disappear for firms beating benchmarks through earnings management. In sum, results suggest that there are benefits associated with beating earnings benchmarks in the debt market. These benefits vary by benchmark, firm default risk, and method utilized to beat the benchmark. Among other implications, this evidence suggests that the relative importance of specific benchmarks differs across the equity and bond markets.

A large-mesh salmon trap: a way of mitigating seal impact on a coastal fishery

Abstract A new design for a salmon trap aimed at minimizing damage to catch and gear caused by grey seals was tested. The traditional trap design used in the northern Baltic permits an efficient hunting strategy by seals, whereby chased fish entangle themselves in the side panels and can then easily be taken, with associated damage to the net. The side panels of the test trap (excluding the fish chamber) are made of large-mesh (400 mm) netting compared to ≤200 mm in traditional traps. This should allow seal-chased and panicking salmon to pass through, while less stressed individuals should still be guided efficiently towards the fish chamber. Trials with the two trap types were performed at the mouth of the river Indal (northern Sweden) in a comparative test programme. Catches of salmon and trout in the test trap were larger than in the standard trap. We estimated that 65% of the potential catch was lost in the standard trap owing to seal predation, while escape rate through the large meshes in the test trap was 52%. The standard trap had a total of 269 holes owing to seal damage, while only six holes were found in the test trap. Seal activity in and around the standard trap was up to 16 times higher compared with the test trap and decreased considerably during the following year when only large-meshed traps were used in the area. We suggest that seals are difficult to deter from fishing gear as long as they get a reward in terms of food and propose that a strategy that deprives seals of a reward will make the gear uninteresting to them and may have long-term mitigation effects.

Pérdidas de fruto y movilización de semillas en <i>Olea europaea</i> var. <i>sylvestris</i> Brot. (Oleaceae)

We analyzed several aspects of the reproductive biology of wild olive ( Olea europaea var. sylvestris . Brot.) related to seed dispersal. The importance of several fruit fates (the way and condition in which fruits leave the tree) is considered in two different habitats, one of which was surveyed in two consecutive years. We distinguished the following fruit fates: (a) consumption by avian seed dispersers (fruit removal), (b) loss due to different biotic (e.g. birds and insects), abiotic (e.g. weather) and plant-controlled factors (e.g. abscission), and (c) fruits remaining on the tree by the end of the season. The ranking of importance of each fruit fate did not differ between habitats, and was similar among individual trees, although the net values of each fate were highly variable among trees. On the average, in the two habitats and seasons the plant investment in fruit crop yielded a low reward in terms of fruit removal success (between 16 and 33 % of the total fruit crop). This was attributable to different factors in the two habitats; in one of them, wild olive fruit crop satiated the scarce avian seed dispersers, whereas in the other, interspecific competition for avian seed dispersers with Phyllirea latifolia probably diminished wild olive removal success. Total fruit losses increased during the second season (from 8 to 40 % of the total fruit crop). However, it did not set a limit to the total amount of seeds being dispersed. Fruit losses were mainly caused by abiotic factors rather than by biotic ones. The percentage of fruits (both unripe and ripe) falling apparently healthy from the branches was higher than the percentage damaged by climatic factors (desiccated and frozen fruits). Among damaging biotic agents (pests and birds), the most frequent one was the larvae of the fly Dacus oleae , followed by birds (both dispersers that drop the fruit while handling and fruit predators) and, accounting for a negligible percentage, the larvae of the moth Prays oleae . By the end of the season, in both plots, a high percentage of the fruit crop remained on the trees (up to 75 % in the first year in one plot). This, together with the high variability between individuals in removal success, suggests a strong intraspecific competition for avian seed dispersers. In conclusion, although removal success in the studied populations was low, our results indicate an important role for dispersers in the success of the fruiting phase as part of the wild olive reproductive cycle.

Adverse health effects of high-effort/low-reward conditions.

In addition to the person-environment fit model (J. R. French, R. D. Caplan, & R. V. Harrison, 1982) and the demand-control model (R. A. Karasek & T. Theorell, 1990), a third theoretical concept is proposed to assess adverse health effects of stressful experience at work: the effort-reward imbalance model. The focus of this model is on reciprocity of exchange in occupational life where high-cost/low-gain conditions are considered particularly stressful. Variables measuring low reward in terms of low status control (e.g., lack of promotion prospects, job insecurity) in association with high extrinsic (e.g., work pressure) or intrinsic (personal coping pattern, e.g., high need for control) effort independently predict new cardiovascular events in a prospective study on blue-collar men. Furthermore, these variables partly explain prevalence of cardiovascular risk factors (hypertension, atherogenic lipids) in 2 independent studies. Studying adverse health effects of high-effort/low-reward conditions seems well justified, especially in view of recent developments of the labor market.

Micro‐level organization

Examines the design of jobs at the micro‐structure or individual level of the organization. Reviews the drawbacks of the scientific management approach to micro‐level job design. Argues that at the level of the individual, managers should be attempting to create a role for each individual that offers a suitable reward in terms of the level of satisfaction perceived to be accrued from taking that role. Advocates the design of work groups as a means of engendering quality and productivity.

Negative Reinforcement and Positive Punishment

The concept of negative reinforcement is notoriously difficult to teach to introductory students. Reasons for this difficulty include: surplus meanings associated with the terms negative and punishment, the fact that Skinner (1938, 1953) described two types of reinforcement but only one type of punishment, the tendency that most students have to view reward and punishment in subjective terms, and Skinner's (1938, 1953) conflicting definitions of reinforcement and punishment. Pointing out to students that there are two types of punishment—positive and negative—as well two types of reinforcement—positive and negative—helps them learn that negative reinforcement is not a synonym for punishment.

INTERVENTION AS THE RATIONAL APPROACH TO CONTROL DISEASES OF MICROBIAL ETIOLOGY TRANSMITTED BY FOODS. An actualization of the tale of the frog and the grouse—after Lafontaine (1621–1695).1

Even advanced countries suffer from infectious diseases spread by food animal origin. The underlying mechanism of this morbidity is known and is important to design measures to reduce the incidence via intervention sensu Wilson (1955).The classical defense lines which rely on high‐level hygiene in the slaughter‐house and during food preparation are insufficient to control these food transmitted enteric infections. Consequently, a third line of defense, processing for safety, is required here as it was in the dairy and the egg product industries. At least two effective modes of processing for safety of raw food animal origin are available to erect this third line of defense. These includ radicidation and lactic acid decontamination. The two procedures lead to marked reward in terms of control of infection, while they are both fully safe.It is the duty of Public Health bacteriologists to advise regulatory agenci and consumers in applying one or both of these measures for improved healt protection.The health profession cannot possibly hope to achieve this goal without recruiting the assistance of experts in human behavior and more particular in factors determining selection and rejection of foods by consumers.

Gradient approach for recursive estimation and control in finite Markov chains

The problem studied is that of controlling a finite Markov chain so as to maximize the long-run expected reward per unit time. The chain's transition probabilities depend upon an unknown parameter taking values in a subset [a, b] of Rn. A control policy is defined as the probability of selecting a control action for each state of the chain. Derived is a Taylor-like expansion formula for the expected reward in terms of policy variations. Based on that result, a recursive stochastic gradient algorithm is presented for the adaptation of the control policy at consecutive times. The gradient depends on the estimated transition parameter which is also recursively updated using the gradient of the likelihood function. Convergence with probability 1 is proved for the control and estimation algorithms.

Gradient approach for recursive estimation and control in finite Markov chains

The problem studied is that of controlling a finite Markov chain so as to maximize the long-run expected reward per unit time. The chain's transition probabilities depend upon an unknown parameter taking values in a subset [ a, b ] of Rn . A control policy is defined as the probability of selecting a control action for each state of the chain. Derived is a Taylor-like expansion formula for the expected reward in terms of policy variations. Based on that result, a recursive stochastic gradient algorithm is presented for the adaptation of the control policy at consecutive times. The gradient depends on the estimated transition parameter which is also recursively updated using the gradient of the likelihood function. Convergence with probability 1 is proved for the control and estimation algorithms.

Recursive Algorithms for Adaptive Control of Finite Markov Chains

The problem of controlling a finite Markov chain so as to maximize the long-run expected reward per unit time is studied. The chain's transition probabilities depend upon an unknown parameter taking values in a subset [a,b] of Rn. A control policy is defined as the probability of selecting a control action for each state of the chain. Derived is a Taylor-like expansion formula for the expected reward in terms of policy variations. Based on that result a recursive stochastic gradient algorithm is presented for the adaptation of the control policy at consecutive times. The gradient depends on the estimated transition parameter which is also recursively updated using the gradient of the likelihood function. Convergence with probability 1 is proved for the control and estimation algorithms.

Recursive algorithms for adaptive control of finite Markov chains

The problem of controlling a finite Markov chain so as to maximize the long-run expected reward per unit time is studied. The chain's transition probabilities depend upon an unknown parameter taking values in a subset [a,b] of Rn. A control policy is defined as the probability of selecting a control action for each state of the chain. Derived is a Taylor-like expansion formula for the expected reward in terms of policy variations. Based on that result a recursive stochastic gradient algorithm is presented for the adaptation of the control policy at consecutive times. The gradient depends on the estimated transition parameter which is also recursively updated using the gradient of the likelihood function. Convergence with probability 1 is proved for the control and estimation algorithms.

Tariffs and welfare of factor owners: A normative extension of the Stolper-Samuelson theorem

The effect of tariffs on real factor rewards in the two-country, twocommodity, two-factor model is well known: ’ the Stolper-SamuelsonMetzler result that, except when the tariff has no effect on the domestic price ratio, tariffs increase one of the factor’s real reward in terms of any commodity price and decrease the others. When the tariff revenue is assumed to be distributed to the public the welfare offactor owners, however, depends not only on real factor rewards but also on their share of the tariff revenue. This raises the question first posed by Bhagwati (1959): under what conditions can the factor that experiences a fall in its real reward, as a result of a tariff, be fully compensated out of the tariff revenue? That one of the factors loses and that the only feasible income transfers may involve ‘dead-weight’ losses makes it interesting to know these conditions, if they exist, under which a country can attain Pareto-superior equilibria by manipulating the tariff rate only and distributing the tariff revenue. Bhagwati (I 959) and Johnson (1960) considered this normative extension of the Stolper-Samuelson

The College Budget

T HE reputation and effectiveness of colleges and universities depend not upon buildings or enrollment but upon the capabilities of the staff engaged in teaching and research. This effectiveness must rest, in the long run, on the activities and the quality of performance of those staff members who receive the greatest reward in terms of promotion or of salary increase. It should be clear, further, that the criteria for promotion and those for increase in salary should be qualitatively the same.' The means, therefore, by which the appropriate activities and the satisfactory quality of performance must be encouraged is the use of the budget as an instrument of personnel policy. In fact, the proper aim in the use of the budget is the continuous improvement of the staff engaged in teaching and research. This point seems to have escaped some administrative officers, who have tried to spread the budget residue for merit increases so that almost everyone on the staff got something and hence could not complain too bitterly. This is so manifestly a misuse of the budget that we must remark that loud and constant complaint may be an indication of a very successful budget

University of Birmingham: Annual Report

THE annual report for the session 1939-40 of the vice-chancellor of the University of Birmingham, Dr. Raymond Priestley, contains many points of interest. Two developments of major importance are the institution of family allowances for members of the staff and the introduction of compulsory physical training. Dr. Priestley, believing that the general tendency of social reform is towards the acceptance of the family rather than the individual as the normal financial unit, has long been a convinced advocate of the principle of family allowances, and he considers that universities should lead rather than follow in such matters, once they are convinced that it is right to move. He “does not fear that the introduction of family allowances will substantially delay or permanently affect the overdue improvement in the salary scales of the middle ranks of the University hierarchy where the shoe admittedly pinches most”. The system is not ideal, because it cannot take account of dependants other than children, but there appears no way of overcoming this drawback without introducing unworkable complications and opening loop-holes which might be unreasonably exploited. Critics lay stress on the principle of equation of reward to quality of service, and so does Dr. Priestley, but he would measure reward in terms of standard of living rather than in money, and he would not have men penalized for having families. The allowance (confined to members of staff whose salary does not exceed £700 per annum) is at the rate of £25 per annum for every child, undergoing full-time education, up to the age of eighteen years. The allowance for the wage-earning staff is 2s, 6d. per week for each child up to the age of sixteen years if undergoing full-time education. The scheme has been in operation since February last year.