The effects of differing response types and price manipulations on demand measures

Animals' behavioral needs have become an important component of animal welfare legislation. Behavioral economics provides a framework for the study of such needs. A function, analogous to a demand function relating consumption rate to price, can be obtained by increasing the price (or work) required for access to a commodity. This experiment investigated the effects of different response types and price manipulations on these functions. Six hens pushed a door or pecked a key for food under open economic conditions (short experimental sessions and supplementary food). In Part 1, the number of door pushes required (fixed-ratio schedule) was increased each session, and the force needed to push the door was increased across conditions. In Part 2, the force needed to push the door was increased session to session, and the fixed-ratio schedule was increased across conditions. In Part 3, the number of key pecks required was increased each session. Both response types produced similarly shaped (approximately linear in logarithmic coordinates and downward sloping) demand functions when price was increased by increasing the number of responses required. These imply an elastic demand for food under these conditions. In contrast, increasing the force required to push the door resulted in highly curvilinear functions. These functions indicated little change in consumption across lower door forces and abrupt drops in consumption at higher force requirements, implying mixed elasticity in the animals' demand for food. The differences between the shapes of the two functions seem to arise from the different ways that the two price manipulations alter the time taken to complete the work required. Increasing the fixed-ratio requirement necessarily increases the time needed to complete each response unit, whereas increasing the force requirement does not. The different shapes of the functions were robust when either force or number was varied across sessions and the value of the other was varied over conditions. They were also robust when the price increases were taken from different conditions, showing that the shapes of the functions were independent of the place in the experiment in which the price was examined. Unit price (which combines number and force into a single price measure) unified the data from the two price manipulations to a large degree, producing moderately curved functions. However, there was some variance around the unit price functions, and this was attributable to the different shapes of the underlying functions. The data suggest that different price manipulations may give different measures of animal demand but that unit price might provide some unification.     

医疗机构单病种限价面面观

单病种限价收费是医院经营的一种管理模式,是指在临床诊疗收费中,对单一病种病人限定最高费用的做法,是医院的一种自发行为。这在一定程度上解决了群众看病难、看病贵的问题,缓解了社会医疗费用过度增长的压力,有助于医疗机构收费更趋于合理化。拟从社会的各个层面对医疗机构单病种限价问题进行深入地探讨。     

The use of social and salience cues in early word learning

This article explores young infants' ability to learn new words in situations providing tightly controlled social and salience cues to their reference. Four experiments investigated whether, given two potential referents, 15-month-olds would attach novel labels to (a) an image toward which a digital recording of a face turned and gazed, (b) a moving image versus a stationary image, (c) a moving image toward which the face gazed, and (d) a gazed-on image versus a moving image. Infants successfully used the recorded gaze cue to form new word-referent associations and also showed learning in the salience condition. However, their behavior in the salience condition and in the experiments that followed suggests that, rather than basing their judgments of the words' reference on the mere presence or absence of the referent's motion, infants were strongly biased to attend to the consistency with which potential referents moved when a word was heard.     

The influence of the immediate visual context on incremental thematic role-assignment: evidence from eye-movements in depicted events

Studies monitoring eye-movements in scenes containing entities have provided robust evidence for incremental reference resolution processes. This paper addresses the less studied question of whether depicted event scenes can affect processes of incremental thematic role-assignment. In Experiments 1 and 2, participants inspected agent-action-patient events while listening to German verb-second sentences with initial structural and role ambiguity. The experiments investigated the time course with which listeners could resolve this ambiguity by relating the verb to the depicted events. Such verb-mediated visual event information allowed early disambiguation on-line, as evidenced by anticipatory eye-movements to the appropriate agent/patient role filler. We replicated this finding while investigating the effects of intonation. Experiment 3 demonstrated that when the verb was sentence-final and thus did not establish early reference to the depicted events, linguistic cues alone enabled disambiguation before people encountered the verb. Our results reveal the on-line influence of depicted events on incremental thematic role-assignment and disambiguation of local structural and role ambiguity. In consequence, our findings require a notion of reference that includes actions and events in addition to entities (e.g. Semantics and Cognition, 1983), and argue for a theory of on-line sentence comprehension that exploits a rich inventory of semantic categories.     

Generation of referring expressions: assessing the Incremental Algorithm

A substantial amount of recent work in natural language generation has focused on the generation of 'one-shot' referring expressions whose only aim is to identify a target referent. Dale and Reiter's Incremental Algorithm (IA) is often thought to be the best algorithm for maximizing the similarity to referring expressions produced by people. We test this hypothesis by eliciting referring expressions from human subjects and computing the similarity between the expressions elicited and the ones generated by algorithms. It turns out that the success of the IA depends substantially on the 'preference order' (PO) employed by the IA, particularly in complex domains. While some POs cause the IA to produce referring expressions that are very similar to expressions produced by human subjects, others cause the IA to perform worse than its main competitors; moreover, it turns out to be difficult to predict the success of a PO on the basis of existing psycholinguistic findings or frequencies in corpora. We also examine the computational complexity of the algorithms in question and argue that there are no compelling reasons for preferring the IA over some of its main competitors on these grounds. We conclude that future research on the generation of referring expressions should explore alternatives to the IA, focusing on algorithms, inspired by the Greedy Algorithm, which do not work with a fixed PO.     

Markers of Topical Discourse in Child‐Directed Speech

Although the language we encounter is typically embedded in rich discourse contexts, many existing models of processing focus largely on phenomena that occur sentence‐internally. Similarly, most work on children's language learning does not consider how information can accumulate as a discourse progresses. Research in pragmatics, however, points to ways in which each subsequent utterance provides new opportunities for listeners to infer speaker meaning. Such inferences allow the listener to build up a representation of the speakers' intended topic and more generally to identify relationships, structures, and messages that extend across multiple utterances. We address this issue by analyzing a video corpus of child–caregiver interactions. We use topic continuity as an index of discourse structure, examining how caregivers introduce and discuss objects across utterances. For the analysis, utterances are grouped into topical discourse sequences using three annotation strategies: raw annotations of speakers' referents, the output of a model that groups utterances based on those annotations, and the judgments of human coders. We analyze how the lexical, syntactic, and social properties of caregiver–child interaction change over the course of a sequence of topically related utterances. Our findings suggest that many cues used to signal topicality in adult discourse are also available in child‐directed speech.     

True Context‐dependent Preferences? The Causes of Market‐dependent Valuations

A central assumption of neoclassical economics is that reservation prices for familiar products express people's true preferences for these products; that is, they represent the total benefit that a good confers to the consumers and are, thus, independent of actual prices in the market. Nevertheless, a vast amount of research has shown that valuations can be sensitive to other salient prices, particularly when individuals are explicitly anchored on them. In this paper, the authors extend previous research on single‐price anchoring and study the sensitivity of valuations to the distribution of prices found for a product in the market. In addition, they examine its possible causes. They find that market‐dependent valuations cannot be fully explained by rational inferences consumers draw about a product's value and are unlikely to be fully explained by true market‐dependent preferences. Rather, the market dependence of valuations likely reflects consumers' focus on something other than the total benefit that the product confers to them. Furthermore, this paper shows that market‐dependent valuations persist when – as in many real‐life settings – individuals make repeated purchase decisions over time and infer the distribution of the product's prices from their market experience. Finally, the authors consider the implications of their findings for marketers and consumers. Copyright © 2013 John Wiley & Sons, Ltd.     

Package size and perceived quality: The intervening role of unit price perceptions

This research examines how package size can influence quality judgments for packaged goods, and also identifies a price-based mechanism for the observed size–quality relationship. Results from several studies show that a product in a smaller package is rated more favorably than the equivalent product in a larger package. Further, this effect is due to the smaller package being associated with a higher unit price (despite having a lower overall price), which suggests that unit price information is more diagnostic than overall price information when forming judgments of product quality. We also find a theoretically-derived reversal of this effect under conditions in which the greater diagnosticity of unit price is overwhelmed by its lower ease of use. Namely, when overall price is the only explicitly-provided price cue and consumers are too distracted to estimate unit price, a larger package is now rated as being better. Finally, two concluding studies examine the downstream consequences of changes in package size, building off our basic conceptualization to document effects on product choice as well as consumption experience.