994 resultados para reinforcment sensitivity theory (RST)


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Real estate development appraisal is a quantification of future expectations. The appraisal model relies upon the valuer/developer having an understanding of the future in terms of the future marketability of the completed development and the future cost of development. In some cases the developer has some degree of control over the possible variation in the variables, as with the cost of construction through the choice of specification. However, other variables, such as the sale price of the final product, are totally dependent upon the vagaries of the market at the completion date. To try to address the risk of a different outcome to the one expected (modelled) the developer will often carry out a sensitivity analysis on the development. However, traditional sensitivity analysis has generally only looked at the best and worst scenarios and has focused on the anticipated or expected outcomes. This does not take into account uncertainty and the range of outcomes that can happen. A fuller analysis should include examination of the uncertainties in each of the components of the appraisal and account for the appropriate distributions of the variables. Similarly, as many of the variables in the model are not independent, the variables need to be correlated. This requires a standardised approach and we suggest that the use of a generic forecasting software package, in this case Crystal Ball, allows the analyst to work with an existing development appraisal model set up in Excel (or other spreadsheet) and to work with a predetermined set of probability distributions. Without a full knowledge of risk, developers are unable to determine the anticipated level of return that should be sought to compensate for the risk. This model allows the user a better understanding of the possible outcomes for the development. Ultimately the final decision will be made relative to current expectations and current business constraints, but by assessing the upside and downside risks more appropriately, the decision maker should be better placed to make a more informed and “better”.

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We reconsider the theory of the linear response of non-equilibrium steady states to perturbations. We �rst show that by using a general functional decomposition for space-time dependent forcings, we can de�ne elementary susceptibilities that allow to construct the response of the system to general perturbations. Starting from the de�nition of SRB measure, we then study the consequence of taking di�erent sampling schemes for analysing the response of the system. We show that only a speci�c choice of the time horizon for evaluating the response of the system to a general time-dependent perturbation allows to obtain the formula �rst presented by Ruelle. We also discuss the special case of periodic perturbations, showing that when they are taken into consideration the sampling can be �ne-tuned to make the de�nition of the correct time horizon immaterial. Finally, we discuss the implications of our results in terms of strategies for analyzing the outputs of numerical experiments by providing a critical review of a formula proposed by Reick.

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In 'Avalanche', an object is lowered, players staying in contact throughout. Normally the task is easily accomplished. However, with larger groups counter-intuitive behaviours appear. The paper proposes a formal theory for the underlying causal mechanisms. The aim is to not only provide an explicit, testable hypothesis for the source of the observed modes of behaviour-but also to exemplify the contribution that formal theory building can make to understanding complex social phenomena. Mapping reveals the importance of geometry to the Avalanche game; each player has a pair of balancing loops, one involved in lowering the object, the other ensuring contact. For more players, sets of balancing loops interact and these can allow dominance by reinforcing loops, causing the system to chase upwards towards an ever-increasing goal. However, a series of other effects concerning human physiology and behaviour (HPB) is posited as playing a role. The hypothesis is therefore rigorously tested using simulation. For simplicity a 'One Degree of Freedom' case is examined, allowing all of the effects to be included whilst rendering the analysis more transparent. Formulation and experimentation with the model gives insight into the behaviours. Multi-dimensional rate/level analysis indicates that there is only a narrow region in which the system is able to move downwards. Model runs reproduce the single 'desired' mode of behaviour and all three of the observed 'problematic' ones. Sensitivity analysis gives further insight into the system's modes and their causes. Behaviour is seen to arise only when the geometric effects apply (number of players greater than degrees of freedom of object) in combination with a range of HPB effects. An analogy exists between the co-operative behaviour required here and various examples: conflicting strategic objectives in organizations; Prisoners' Dilemma and integrated bargaining situations. Additionally, the game may be relatable in more direct algebraic terms to situations involving companies in which the resulting behaviours are mediated by market regulations. Finally, comment is offered on the inadequacy of some forms of theory building and the case is made for formal theory building involving the use of models, analysis and plausible explanations to create deep understanding of social phenomena.

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The assumption that ‘states' primary goal is survival’ lies at the heart of the neorealist paradigm. A careful examination of the assumption, however, reveals that neorealists draw upon a number of distinct interpretations of the ‘survival assumption’ that are then treated as if they are the same, pointing towards conceptual problems that surround the treatment of state preferences. This article offers a specification that focuses on two questions that highlight the role and function of the survival assumption in the neorealist logic: (i) what do states have to lose if they fail to adopt self-help strategies?; and (ii) how does concern for relevant losses motivate state behaviour and affect international outcomes? Answering these questions through the exploration of governing elites' sensitivity towards regime stability and territorial integrity of the state, in turn, addresses the aforementioned conceptual problems. This specification has further implications for the debates among defensive and offensive realists, potential extensions of the neorealist logic beyond the Westphalian states, and the relationship between neorealist theory and policy analysis.

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The absorption coefficient of a substance distributed as discrete particles in suspension is less than that of the same material dissolved uniformly in a medium—a phenomenon commonly referred to as the flattening effect. The decrease in the absorption coefficient owing to flattening effect depends on the concentration of the absorbing pigment inside the particle, the specific absorption coefficient of the pigment within the particle, and on the diameter of the particle, if the particles are assumed to be spherical. For phytoplankton cells in the ocean, with diameters ranging from less than 1 µm to more than 100 µm, the flattening effect is variable, and sometimes pronounced, as has been well documented in the literature. Here, we demonstrate how the in vivo absorption coefficient of phytoplankton cells per unit concentration of its major pigment, chlorophyll a, can be used to determine the average cell size of the phytoplankton population. Sensitivity analyses are carried out to evaluate the errors in the estimated diameter owing to potential errors in the model assumptions. Cell sizes computed for field samples using the model are compared qualitatively with indirect estimates of size classes derived from high performance liquid chromatography data. Also, the results are compared quantitatively against measurements of cell size in laboratory cultures. The method developed is easy-to-apply as an operational tool for in situ observations, and has the potential for application to remote sensing of ocean colour data.

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In this paper we provide a connection between the geometrical properties of the attractor of a chaotic dynamical system and the distribution of extreme values. We show that the extremes of so-called physical observables are distributed according to the classical generalised Pareto distribution and derive explicit expressions for the scaling and the shape parameter. In particular, we derive that the shape parameter does not depend on the cho- sen observables, but only on the partial dimensions of the invariant measure on the stable, unstable, and neutral manifolds. The shape parameter is negative and is close to zero when high-dimensional systems are considered. This result agrees with what was derived recently using the generalized extreme value approach. Combining the results obtained using such physical observables and the properties of the extremes of distance observables, it is possible to derive estimates of the partial dimensions of the attractor along the stable and the unstable directions of the flow. Moreover, by writing the shape parameter in terms of moments of the extremes of the considered observable and by using linear response theory, we relate the sensitivity to perturbations of the shape parameter to the sensitivity of the moments, of the partial dimensions, and of the Kaplan–Yorke dimension of the attractor. Preliminary numer- ical investigations provide encouraging results on the applicability of the theory presented here. The results presented here do not apply for all combinations of Axiom A systems and observables, but the breakdown seems to be related to very special geometrical configurations.

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This paper presents an open-source canopy height profile (CHP) toolkit designed for processing small-footprint full-waveform LiDAR data to obtain the estimates of effective leaf area index (LAIe) and CHPs. The use of the toolkit is presented with a case study of LAIe estimation in discontinuous-canopy fruit plantations. The experiments are carried out in two study areas, namely, orange and almond plantations, with different percentages of canopy cover (48% and 40%, respectively). For comparison, two commonly used discrete-point LAIe estimation methods are also tested. The LiDAR LAIe values are first computed for each of the sites and each method as a whole, providing “apparent” site-level LAIe, which disregards the discontinuity of the plantations’ canopies. Since the toolkit allows for the calculation of the study area LAIe at different spatial scales, between-tree-level clumpingcan be easily accounted for and is then used to illustrate the impact of the discontinuity of canopy cover on LAIe retrieval. The LiDAR LAIe estimates are therefore computed at smaller scales as a mean of LAIe in various grid-cell sizes, providing estimates of “actual” site-level LAIe. Subsequently, the LiDAR LAIe results are compared with theoretical models of “apparent” LAIe versus “actual” LAIe, based on known percent canopy cover in each site. The comparison of those models to LiDAR LAIe derived from the smallest grid-cell sizes against the estimates of LAIe for the whole site has shown that the LAIe estimates obtained from the CHP toolkit provided values that are closest to those of theoretical models.

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Complex networks obtained from real-world networks are often characterized by incompleteness and noise, consequences of imperfect sampling as well as artifacts in the acquisition process. Because the characterization, analysis and modeling of complex systems underlain by complex networks are critically affected by the quality and completeness of the respective initial structures, it becomes imperative to devise methodologies for identifying and quantifying the effects of the sampling on the network structure. One way to evaluate these effects is through an analysis of the sensitivity of complex network measurements to perturbations in the topology of the network. In this paper, measurement sensibility is quantified in terms of the relative entropy of the respective distributions. Three particularly important kinds of progressive perturbations to the network are considered, namely, edge suppression, addition and rewiring. The measurements allowing the best balance of stability (smaller sensitivity to perturbations) and discriminability (separation between different network topologies) are identified with respect to each type of perturbation. Such an analysis includes eight different measurements applied on six different complex networks models and three real-world networks. This approach allows one to choose the appropriate measurements in order to obtain accurate results for networks where sampling bias cannot be avoided-a very frequent situation in research on complex networks.

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A dislocation model, accurately describing the uniaxial plastic stress-strain behavior of dual phase (DP) steels, is proposed and the impact of martensite content and ferrite grain size in four commercially produced DP steels is analyzed. It is assumed that the plastic deformation process is localized to the ferrite. This is taken into account by introducing a non-homogeneity parameter, f(e), that specifies the volume fraction of ferrite taking active part in the plastic deformation process. It is found that the larger the martensite content the smaller the initial volume fraction of active ferrite which yields a higher initial deformation hardening rate. This explains the high energy absorbing capacity of DP steels with high volume fractions of martensite. Further, the effect of ferrite grain size strengthening in DP steels is important. The flow stress grain size sensitivity for DP steels is observed to be 7 times larger than that for single phase ferrite.

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Aims. To investigate the role of sensitivity to reward in mediating social drinkers' reactivity to alcohol cues. Design. A standard cue-reactivity paradigm was employed. Two groups of social drinkers (heavy and ight) were assessed after exposure to the sight, smell and taste of a neutral cue (water) and then an alcohol cue (glass of beer). Setting. Sessions were conducted in a laboratory based environment. Participants. Twenty heavy (12 males, eight females) and 18 light social drinkers (seven males, 11 females) were recruited; mean age was 23.6 years. Measurements. The Card Arranging Reward Responsivity Objective Test (CARROT), assessing behavioural responsiveness to a monetary incentive; urge to drink; positive affect; and the BAS scales, assessing sensitivity to reward. Findings. Heavy drinkers displayed a significant increase in responsivity to rewards (i.e. CARROT) and self-reported urge to drink, bur not positive affect, after exposure to alcohol. For the heavy drinkers, heightened sensitivity to reward (i.e. BAS scales) was significantly related to cue-elicited urge to drink and positive affect. Conclusion. The results are consistent with a conditioned appetitive motivational model of alcohol use and suggest that Gray's theory of personality may be of some benefit in explaining variation in reactivity responses.

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Purpose – Rest posited that to behave morally, an individual must have performed at least four basic psychological processes: moral sensitivity; moral judgment; moral motivation; and moral character. Though much ethics research in accounting has been focused on component two, ethical judgment, less research has been undertaken on the other three components. The purpose of this study is to focus on component one, ethical sensitivity, of Rest's four-component model.
Design/methodology/approach – A sample of 156 accounting undergraduates was employed to investigate the ethical sensitivity of accounting students and the effects of their ethical reasoning and personal factors on their ethical sensitivity.
Findings – Results of this study show that accounting students vary in their ability to detect the presence of ethical issues in a professional scenario. There is no significant relationship between accounting students' ethical sensitivity and their ethical reasoning (P-score). Accounting students characterized as “internals” are more likely to show an ability to recognize ethical issues than those characterized as “externals.” The results also indicate that an accounting ethics intervention may have positive effect on accounting students' ethical sensitivity development. Hence, an individual who possesses the ability to determine what is ethically right or wrong (high ethical reasoning) may fail to behave ethically due to a deficiency in identifying ethical issues (low ethical sensitivity) in a situation.
Originality/value – Whilst much research has concentrated on ethical reasoning and ethics education to enhance the ethical conduct of accountants, it is important that the profession and researchers also direct their attention and efforts to cultivating the ethical sensitivity of accountants. The findings of this study provide additional evidence to support Rest's theory of a more comprehensive cognitive model of ethical decision-making and suggest a more balanced research effort in evaluating the ethical development of individuals.

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The purpose of this study was to test whether calculated inclusion of cultural sensitivity in a selected entrepreneurial business planning (EBP) process could increase sales growth in a test market and to explore the implications of a positive answer for the theory and practice of entrepreneurial business planning. Execution of a pretest-posttest control group experimental design measured and compared the implemented effectiveness of a planned entrepreneurial initiative based on cultural sensitivity. Though small in scale and limited in focus, the initiative qualified as an example of entrepreneurial business planning (EBP) and could be used to apply, test and extend aspects of the developing theory in this field of entrepreneurship research. Since the initiative was planned to overcome a culturally-defined impediment to business growth, it also offered opportunity to explore the specific importance of cultural variables in the context of EBP.

A planned sales-promotion was offered to a control group (receiving information in English) and a treatment group (who received the information in the language of ethnic origin). The sixty subjects had been chosen at random from a population of route-trade retailers of defined ethnic origins (Greek, Lebanese and Chinese) and randomly assigned to control and treatment groups. Monthly sales averages of the promoted product were measured before and after treatment. A Chi Square test was used to evaluate the relative proportion of the control and treatment groups who accepted the promotional offer. A two sample t-test procedure and complementary non-parametric Mann-Whitney test were performed to compare the mean sales-performance change of the two groups. Analysis showed that there was a significant increase in mean sales when the planned entrepreneurial initiative was communicated in the relevant language of origin.

The experimental results have specific practical relevance to revitalising the deteriorating route-trade segment of the Australian confectionery market through increasing the sales growth of wholesalers who are prepared to act entrepreneurially and include cultural sensitivity as an element in planning and implementation. By introducing cultural sensitivity as a necessary extension of a plan’s communications role, the results also have general theoretical implications for the developing paradigm of entrepreneurial business planning.

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This paper offers a brief review of research on the impact of bullying and racism on Aboriginal and Torres Strait Islander peoples within Australia. The overarching emphasis was on the variety of physical, social, mental, and educational outcomes for Aboriginal and Torres Strait Islander children and youth, whilst also critiquing the prevailing literature with regard to its inclusion and sensitivity towards the importance of culture and connected values. Within the Aboriginal and Torres Strait Islander research setting, although a strong base of research on the impact of racism has emerged, research on the impact of bullying is more recent. In addition, while there may be considerable overlap as to the individual impact of bullying and racism, racism research has identified a wider cultural/identity-threat that bullying research (with a few exceptions) has largely ignored. As a result, there is a need to be sensitive to cultural differences with regard to both the types and effects of racism and bullying, and that efforts to understand and to lessen the prevalence of racism and bullying should be framed within the development of a culturally sensitive and secure framework (Coffin, 2008).

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In this paper we examine the properties of a hybrid auction that combines a sealed bid and an ascending auction. In this auction, each bidder submits a sealed bid. Once the highest bid is known, the bidder who submitted it is declared the winner if her bid is higher than the second highest by more than a predetermined amount or percentage. If at least one more bidder submitted a bid su¢ciently close to the highest bid (that is, if the di¤erence between this bid and the highest bid is smaller than the predetermined amount or percentage) the quali…ed buyers compete in an open ascending auction that has the highest bid of the …rst stage as the reserve price. Quali…ed bidders include not only the highest bidder in the …rst stage but also those who bid close enough to her. We show that this auction generates more revenue than a standard auction. Although this hybrid auction does not generate as much revenue as the optimal auction, it is ex-post e¢cient.