Two New Proofs of Afriat's Theorem

We provide two new, simple proofs of Afriat's celebrated theorem stating that a finite set of price-quantity observations is consistent with utility maximization if, and only if, the observations satisfy a variation of the Strong Axiom of Revealed Preference known as the Generalized Axiom of Revealed Preference.Afriat's theorem, SARP, GARP

Sheeple? The need for more research on sheep cognition

Marino & Merskin (2019) provide a comprehensive review of the cognitive abilities of sheep. If research with other animals is any guide, there may be justification for the view that the abilities of sheep have been underestimated, and their review will likely stimulate more research into sheep cognition

A spoon full of studies helps the comparison go down: a comparative analysis of Tulving’s spoon test

Mental time travel refers to the ability to cast one’s mind back in time to re-experience a past event and forward in time to pre-experience events that may occur in the future. Endel Tulving (2005), an authority on mental time travel, holds that this ability is unique to humans. Anticipating that comparative psychologists would challenge this claim, Tulving (2005) proposed his spoon test, a test specifically designed to assess whether nonhuman animals are capable of mental time travel. A number of studies have now employed the spoon test to assess mental time travel in nonhuman animals. Here, we review the evidence for mental time travel in primates. To provide a benchmark, we also review studies that have employed the spoon test with preschool children. The review demonstrates that if we compare the performance of great apes to that of preschool children, and hold them to the same criteria, the data suggest mental travel is present but not ubiquitous in great apes

Very superstitious? A preliminary investigation of pigeons’ body position during a matching-to-sample task under differential and common outcome conditions.

The delayed matching-to-sample (DMS) task is widely employed to assess memory in a range of non-human animals. On the standard “common outcomes” (CO) DMS task, correct performance following either sample stimulus results in reinforcement. In contrast, on a “differential outcomes” (DO) DMS task, the outcome following either sample stimulus is different. One of the most consistent findings in the comparative literature is that performance under a DO condition is superior to that under a CO condition. The superior performance is attributed to the fact the DO condition enhances memory for the sample stimulus by tagging each sample with a discrete reward. Here, we investigate an alternative possibility, that pigeons use positional mediation during the delay under DO, but not CO, conditions. To test this, we tracked the head position of pigeons performing a DO (n = 4) or CO (n = 4) task. Consistent with the positional mediation account, all subjects in the DO condition displayed evidence of positional mediation. Surprisingly, positional mediation was not unique to subjects in the DO condition, with subjects in the CO condition also displaying evidence of mediation.&nbsp

Participatory Monitoring of Community-Based Rehabilitation and other Disability- Inclusive Development Programmes: the Development of a Manual and Menu

Purpose: This paper describes a three-year research project leading to the development of the CBR Monitoring Manual and Menu (MM&M). The MM&M is a practical toolkit that meets the needs of CBR managers and stakeholders, and is consistent with the philosophy of CBR and community-based disability-inclusive development. It is designed to produce meaningful and locally useful information and data, based on international data standards where possible, to enable aggregation at regional, national and international levels. Methods: Five complementary workstreams of research were carried out from 2011 to 2014: 1) literature review and analysis; 2) participatory action research with CBR stakeholders; 3) analysis and refinement of validity of concepts and structures; 4) consultation and review; and 5) synthesis of results. This article documents the method and key results of each of the five workstreams, and the lessons learned along the way. Results: The MM&M is now freely available on-line at http://sydney.edu.au/health-sciences/cdrp/projects/cbr-monitoring.shtml. Collaboration among members of the development team continues, chiefly via an on-line group to which new members have been welcomed. Conclusion and Implications: At the time of writing, the MM&M is the only international monitoring product, known to the authors, that consciously sets out to reflect both a ‘bottom- up’ and ‘top-down’ perspective of monitoring information and data. To achieve this for a complex programme such as CBR, and to align with its principles, it was essential to use a multi-component and multi-stage strategy for tool development, involving a diverse multidisciplinary team includingcollaboration with CBR stakeholders

Two New Proofs of Afriat\u27s Theorem

We provide two new, simple proofs of Afriat’s celebrated theorem stating that a finite set of price-quantity observations is consistent with utility maximization if, and only if, the observations satisfy a variation of the Strong Axiom of Revealed Preference known as the Generalized Axiom of Revealed Preference

Brain Cells in the Avian ‘Prefrontal Cortex’ Code for Features of Slot-Machine-Like Gambling

Slot machines are the most common and addictive form of gambling. In the current study, we recorded from single neurons in the ‘prefrontal cortex’ of pigeons while they played a slot-machine-like task. We identified four categories of neurons that coded for different aspects of our slot-machine-like task. Reward-Proximity neurons showed a linear increase in activity as the opportunity for a reward drew near. I-Won neurons fired only when the fourth stimulus of a winning (four-of-a-kind) combination was displayed. I-Lost neurons changed their firing rate at the presentation of the first nonidentical stimulus, that is, when it was apparent that no reward was forthcoming. Finally, Near-Miss neurons also changed their activity the moment it was recognized that a reward was no longer available, but more importantly, the activity level was related to whether the trial contained one, two, or three identical stimuli prior to the display of the nonidentical stimulus. These findings not only add to recent neurophysiological research employing simulated gambling paradigms, but also add to research addressing the functional correspondence between the avian NCL and primate PFC