Counting by Identity: A Reply to Liebesman

David Liebesman (AJP, 2015) argues that we never count by identity. He generalizes from an argument that we don't do so with sentences indicating fractions, or with measurement sentences on their supposed count readings. In response, I argue that measurement sentences aren't covered by the thesis that we count by identity, in part because they don't have count readings. Then I use the data to which Liebesman appeals, in his argument that we don't count by identity using measurement sentences, in order to rebut his argument that we don't count by identity using sentences indicating fractions.     

Dog rivalry impacts following behavior in a decision-making task involving food

Dogs learn a great deal from humans and other dogs. Previous studies of socially influenced learning between dogs have typically used a highly trained demonstrator dog who is unfamiliar to the observer. Because of this, it is unknown how dynamics between familiar dogs may influence their likelihood of learning from each other. In this study, we tested dogs living together in two-dog households on whether individual dogs’ rivalry scores were associated with performance on a local enhancement task. Specifically, we wanted to know whether dog rivalry impacted whether an observer dog would approach a plate from which a demonstrator dog had eaten all available food, or whether the observer dog would approach the adjacent plate that still contained food. Dog rivalry scores were calculated using the Canine Behavioral Assessment and Research Questionnaire and indicated each dog’s tendency to engage aggressively with the other household dog. Low-rivalry dogs were more likely to approach the empty plate than high-rivalry dogs when the observer dog was allowed to approach the plates immediately after the demonstrator had moved out of sight. This difference between low- and high-rivalry dogs disappeared, however, when observer dogs had to wait 5 s before approaching the plates. The same pattern was observed during a control condition when a human removed the food from a plate. Compared to low-rivalry dogs, high-rivalry dogs may pay less attention to other dogs due to a low tolerance for having other dogs in close proximity.     

Habituation and dishabituation during object play in kennel-housed dogs

Domestic dogs are reported to show intense but transient neophilia towards novel objects. Here, we examine habituation and dishabituation to manipulable objects by kennel-housed dogs. Labrador retrievers (N?=?16) were repeatedly presented with one toy for successive 30-s periods until interaction ceased. At this point (habituation), a different toy was presented that contrasted with the first in both colour and odour (since the dog’s saliva would have accumulated on the first), colour alone, or odour alone. No effect of the type of contrast was detected in the number of presentations to habituation, the difference in duration of interaction between the first presentation of the first toy and the presentation of the second toy (recovery), or the duration of interaction with the second toy (dishabituation). Varying the time interval between successive presentations of the first toy up to habituation between 10?s and 10?min had no effect on the number of presentations to habituation, nor did it alter the extent of dishabituation. Varying the delay from habituation to presentation of the second toy, between 10?s and 15?min, affected neither the recovery nor the dishabituation. Overall, the study indicates that loss of interest in the object during object-orientated play in this species is due to habituation to the overall stimulus properties of the toy rather than to any single sensory modality and is also atypical in its insensitivity to the interval between presentations.     

Evaluating a humane alternative to the bark collar: Automated differential reinforcement of not barking in a home‐alone setting

The aim of this study was to develop a humane alternative to the traditional remote devices that deliver punishers contingent on home‐alone dog barking. Specifically, we evaluated the use of remote delivery of food contingent on intervals of not barking during the pet owner's absence. In Experiment 1, 5 dogs with a history of home‐alone nuisance barking were recruited. Using an ABAB reversal design, we demonstrated that contingent remote delivery of food decreased home‐alone barking for 3 of the dogs. In Experiment 2, we demonstrated that it is possible to thin the differential‐reinforcement‐of‐other‐behavior (DRO) schedule gradually, resulting in a potentially more acceptable treatment. Our results benefit the dog training community by providing a humane tool to combat nuisance barking.     

Visual categorization of natural stimuli by domestic dogs

One of the fundamental issues in the study of animal cognition concerns categorization. Although domestic dogs (Canis familiaris) are on the brink to become one of the model animals in animal psychology, their categorization abilities are unknown. This is probably largely due to the absence of an adequate method for testing dogs’ ability to discriminate between large sets of pictures in the absence of human cueing. Here we present a computer-automated touch-screen testing procedure, which enabled us to test visual discrimination in dogs while social cueing was ruled out. Using a simultaneous discrimination procedure, we first trained dogs (N = 4) to differentiate between a set of dog pictures (N = 40) and an equally large set of landscape pictures. All subjects learned to discriminate between the two sets and showed successful transfer to novel pictures. Interestingly, presentation of pictures providing contradictive information (novel dog pictures mounted on familiar landscape pictures) did not disrupt performance, which suggests that the dogs made use of a category-based response rule with classification being coupled to category-relevant features (of the dog) rather than to item-specific features (of the background). We conclude that dogs are able to classify photographs of natural stimuli by means of a perceptual response rule using a newly established touch-screen procedure. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Training of instrumental responses in dogs socially reinforced by humans

The motivational bases of the social reinforcement in human-dog relations were examined. In experiment I, performed on seven dogs, it was found that dogs were able to learn and sustain the natural responses of sitting, paw extension, and lying prostrate to conditional stimuli in the form of vocal commands reinforced only by social rewards given by the experimenter, such as petting and vocal encouragement. Overtraining did not produce deterioration of performance but, on the contrary, the continual decrease of latencies. It was evidenced that tactile stimulation plays an important role in social reward. In experiment II, instrumental responses to the auditory conditional stimuli were elaborated in two groups of dogs. The first group (nine dogs) was reinforced by food, and the second group (eight dogs) was reinforced exclusively by petting. A similar course of learning and level of performance during overtraining sessions in both groups indicated that petting serves as a good reinforcement, with rewarding value comparable to that of food reinforcement. It is suggested that a strong rewarding effect of pleasurable sensory stimuli occurs in the formation of the bond between dog and human and in the learning of different tasks.     

How does dominance rank status affect individual and social learning performance in the dog (<Emphasis Type="Italic">Canis familiaris</Emphasis>)?

Dogs can learn effectively to detour around a V-shaped fence after observing a demonstration from either an unfamiliar human or dog demonstrator. We found earlier that there is substantial individual variation between the dogs’ performance, even when using the same experimental conditions. Here, we investigate if the subjects’ relative dominance rank with other dogs had an effect on their social learning performance. On the basis of the owners’ answers to a questionnaire, subjects from multi-dog homes were sorted into groups of dominant and subordinate dogs. In Experiment 1, dominant and subordinate dogs were tested without demonstration and we did not find any difference between the groups—they had similarly low detour performances on their own. In Experiment 2 and 3, dogs from single dog and multi-dog households were tested in the detour task with demonstration by an unfamiliar dog, or human, respectively. The results showed that social learning performance of the single dogs fell between the dominant and subordinate multi-dogs with both dog and human demonstration. Subordinate dogs displayed significantly better performance after having observed a dog demonstrator in comparison to dominant dogs. In contrast, the performance of dominant and subordinate dogs was almost similar, when they observed a human demonstrator. These results suggest that perceived dominance rank in its own group has a strong effect on social learning in dogs, but this effect seems to depend also on the demonstrator species. This finding reveals an intricate organization of the social structure in multi-dog households, which can contribute to individual differences existing among dogs.     

How do children view and categorise human and dog facial expressions?

Children are often surrounded by other humans and companion animals (e.g., dogs, cats); and understanding facial expressions in all these social partners may be critical to successful social interactions. In an eye-tracking study, we examined how children (4–10 years old) view and label facial expressions in adult humans and dogs. We found that children looked more at dogs than humans, and more at negative than positive or neutral human expressions. Their viewing patterns (Proportion of Viewing Time, PVT) at individual facial regions were also modified by the viewed species and emotion, with the eyes not always being most viewed: this related to positive anticipation when viewing humans, whilst when viewing dogs, the mouth was viewed more or equally compared to the eyes for all emotions. We further found that children's labelling (Emotion Categorisation Accuracy, ECA) was better for the perceived valence than for emotion category, with positive human expressions easier than both positive and negative dog expressions. They performed poorly when asked to freely label facial expressions, but performed better for human than dog expressions. Finally, we found some effects of age, sex, and other factors (e.g., experience with dogs) on both PVT and ECA. Our study shows that children have a different gaze pattern and identification accuracy compared to adults, for viewing faces of human adults and dogs. We suggest that for recognising human (own-face-type) expressions, familiarity obtained through casual social interactions may be sufficient; but for recognising dog (other-face-type) expressions, explicit training may be required to develop competence.

Highlights

• We conducted an eye-tracking experiment to investigate how children view and categorise facial expressions in adult humans and dogs
• Children's viewing patterns were significantly dependent upon the facial region, species, and emotion viewed
• Children's categorisation also varied with the species and emotion viewed, with better performance for valence than emotion categories
• Own-face-types (adult humans) are easier than other-face-types (dogs) for children, and casual familiarity (e.g., through family dogs) to the latter is not enough to achieve perceptual competence

     

How Power States Influence the Persuasiveness of Top‐Dog versus Underdog Appeals

Although both top‐dog and underdog positioning appeals are widely used in marketing and advertising, little is known about which strategy is more effective in persuading consumers. By introducing a sense of power, a social variable that is inherently relevant to the nature of the top‐dog versus underdog classification, we propose that consumers' responses to these two appeals are influenced by their psychological experience of power. Specifically, low‐power consumers will respond to top‐dog appeals more favorably because associating with top dogs facilitates power restoration. In contrast, high‐power consumers will respond to underdog appeals more favorably because supporting underdogs facilitates power expression. In four experimental studies, we provide consistent support for our main predictions as well as the underlying processes. Studies 1 and 2 demonstrate the differential effect of consumers' power states on their attitudes toward top‐dog versus underdog appeals. Providing process evidence, Studies 3 and 4 identify boundary conditions under which the basic effect was eliminated. These findings contribute to the persuasion literature and power research and provide important implications for positioning strategy and advertisement development.     

What do dogs (<Emphasis Type="Italic">Canis familiaris</Emphasis>) see? A review of vision in dogs and implications for cognition research

Over the last 20 years, a large amount of research has been conducted in an attempt to uncover the cognitive abilities of the domestic dog. While substantial advancements have been made, progress has been impeded by the fact that little is known about how dogs visually perceive their external environment. It is imperative that future research determines more precisely canine visual processing capabilities, particularly considering the increasing number of studies assessing cognition via paradigms requiring vision. This review discusses current research on visual cognition and emphasizes the importance of understanding dog visual processing. We review several areas of vision research in domestic dogs, such as sensitivity to light, visual perspective, visual acuity, form perception, and color vision, with a focus on how these abilities may affect performance in cognition tasks. Additionally, we consider the immense diversity seen in dog morphology and explore ways in which these physical differences, particularly in facial morphology, may result in, or perhaps even be caused by, different visual processing capacities in dogs. Finally, we suggest future directions for research in dog vision and cognition.     

An attempt to condition components of urine formation in dogs

Previous research on the renal conditional reflex (CR) has resulted in contradictory data. The work of Bykov with dogs and of Hoferet al. with humans indicated that a renal CR is possible, but the experiments of Corsonet al. and Watt and Gantt with dogs having normal or transplanted cervical kidneys showed no clear-cut renal CR’s. The present work supports the latter finding. Three female mongrel dogs were used. One dog (normal) had an externalized ureter; the other two (experimental) had denervated cervical kidneys (autografts). In 155 days of experiments, the investigators found diuresis to occur only on unconditional stimulus,i.e., only when a dog drank diluted milk (one part milk to four parts water)ad lib.; the dogs drank an average of between 500 and 1,100 ml. No diuresis occurred when 30 ml. of the mixture were given (conditional stimulus). Urinalysis indicated a lack of renal conditioning with respect to the excretion rates and the concentrations of creatinine and electrolytes, except for the sodium concentration in the normal dog’s urine, which decreased on bothad lib and test (30 ml) days; the volume was not affected. Conclusion: Drinking a small quantity of diluted milk as a conditional stimulus did not produce a conditional diuretic response either in the normal dog or in the two dogs with transplanted kidneys.     

Can dogs count?

Numerical competencies have been thoroughly examined in several species, yet relatively few studies have examined such processes in the domestic dog. In an initial experiment, procedures from numerical studies of chimpanzees (0010 and 0015) were adapted for use with 27 domestic dogs. Subjects in these experiments watched as different quantities of food were sequentially dropped into each of two bowls. The subjects were then allowed to select and consume the contents of one of the bowls. Although dogs excelled in a 1 vs 0 condition, their performance failed to significantly surpass chance across all other ratios. In a second experiment with a single subject (a rough collie named Sedona), the procedure was revised so that non-food stimuli were presented simultaneously to the dog on two magnet boards. If Sedona chose the board with the majority of the items, she was rewarded with a piece of food hidden underneath the board. If she made an incorrect choice, she received no reinforcement. Interestingly, Sedona's performance far exceeded that of the dogs in Experiment 1. Implications of these findings for the study of domestic dogs are discussed.     

Can dogs use vocal intonation as a social referencing cue in an object choice task?

Evidence from the literature indicates that dogs’ choices can be influenced by human-delivered social cues, such as pointing, and pointing combined with facial expression, intonation (i.e., rising and falling voice pitch), and/or words. The present study used an object choice task to investigate whether intonation conveys unique information in the absence of other salient cues. We removed facial expression cues and speech information by delivering cues with the experimenter’s back to the dog and by using nonword vocalizations. During each trial, the dog was presented with pairs of the following three vocal cues: Positive (happy-sounding), Negative (sad-sounding), and Breath (neutral control). In Experiment 1, where dogs received only these vocal cue pairings, dogs preferred the Positive intonation, and there was no difference in choice behavior between Negative or Breath. In Experiment 2, we included a point cue with one of the two vocal cues in each pairing. Here, dogs preferred containers receiving pointing cues as well as Negative intonation, and preference was greatest when both of these cues were presented together. Taken together, these findings indicate that dogs can indeed extract information from vocal intonation alone, and may use intonation as a social referencing cue. However, the effect of intonation on behavior appears to be strongly influenced by the presence of pointing, which is known to be a highly salient visual cue for dogs. It is possible that in the presence of a point cue, intonation may shift from informative to instructive.     

Old dog,new tricks: Age differences in dog personality traits,associations with human personality traits,and links to important outcomes

Work examining dog personality is relatively new, so the degree to which dog personality differs by age, predicts important dog outcomes, and is correlated with human personality is unclear. In a sample of 1681 dogs (M_age = 6.44 years, SD = 3.82; 46.2% Female; 50% purebred) and their owners, older dogs were less active/excitable compared to younger dogs. Aggression toward people, responsiveness to training, and aggression toward other animals were highest among 6–8 year old dogs. Dog personality was associated with important dog outcomes—chronic health conditions, biting history, and human-dog relationships. We build on previous research by examining demographic differences in dog personality and associations between dog personality and outcomes for both dogs and humans.     

Coherence and coreference

Coherence in conversations and in texts can be partially characterized by a set of coherence relations, motivated ultimately by the speaker's or writer's need to be understood. In this paper, formal definitions are given for several coherence relations, based on the operations of an inference system; that is, the relations between successive portions of a discourse are characterized in terms of the inferences that can be drawn from each. In analyzing a discourse, it is frequently the case that we would recognize it as coherent, in that it would satisfy the formal definition of some coherence relation, if only we could assume certain noun phrases to be coreferential. In such cases, we will simply assume the identity of the entities referred to, in what might be called a “petty conversational implicature,” thereby solving the coherence and coreference problems simultaneously. Three examples of different kinds of reference problems are presented. In each, it is shown how the coherence of the discourse can be recognized, and how the reference problems are solved, almost as a by-product, by means of these petty conversational implicatures.     

Domestic dogs (Canis familiaris) coordinate their actions in a problem-solving task

Cooperative hunting is a cognitively challenging activity since individuals have to coordinate movements with a partner and at the same time react to the prey. Domestic dogs evolved from wolves, who engage in cooperative hunting regularly, but it is not clear whether dogs have kept their cooperative hunting skills. We presented pairs of dogs with a reward behind a fence with two openings in it. A sliding door operated by the experimenter could block one opening but not both simultaneously. The dogs needed to coordinate their actions, so that each was in front of a different opening, if one of them was to cross through and get food. All 24 dog pairs solved the problem. In study 1, we demonstrated that dogs understood how the apparatus worked. In study 2, we found that, although the performance of the pairs did not depend on the divisibility of the reward, pairs were quicker at coordinating their actions when both anticipated rewards. However, the dogs did not monitor one another, suggesting that their solutions were achieved by each individual attempting to maximize for itself.     

Why Do Some Owners Allow Their Dogs to Foul the Pavement? The Social Psychology of a Minor Rule Infraction1

This study combines observational, attitudinal, and self‐report measures, and compares a group of irresponsible dog owners who allow their dogs to foul with a control group of responsible owners who clean up after their dogs. The owners are compared on a variety of attitudinal and personal orientation measures. We observed 101 instances of dog fouling in both park and pavement, and 87 respondents subsequently returned questionnaires. The majority (59%) of people observed cleaned up after their dogs. The irresponsible owners were significantly more tolerant of fouling (dog feces were seen as natural waste and biodegradable) and were more likely to agree that the laws were illegitimate and restrictive.     

Pointing gestures modulate domestic dogs’ search behavior for hidden objects in a spatial rotation problem

In the spatial domain, domestic dogs are highly inclined to search at the last location where they saw an object disappear and cannot infer that a hidden object has moved imperceptibly from one location to another. In the current study, we examined whether exposure to human social cues modulates dogs’ search behavior for hidden objects. In Experiment 1, twenty dogs were first trained to find an object they saw disappear inside a stationary container in the presence (social group) or absence (non-social group) of pointing gestures. In tests, the containers were rotated 180° around a central axis. The dogs in the non-social group systematically searched at the initial (now incorrect) hiding location, whereas the dogs in the social group chose correctly significantly above chance. In Experiment 2, we tested whether pre-exposure to human pointing has an impact on dogs’ use of gestures. No gestures were given during training and both the social and non-social conditions were administered to each of the ten dogs. In contrast to Experiment 1, the performance of dogs in the social condition dropped significantly and varied substantially from one dog to another. Overall, this study suggests that dogs’ tendency to use human signals is so strong that it even outweighs their spatial bias to search where they saw an object disappear; however, this penchant to use human gestures appears to be dependent on the degree of familiarity of the dog with these signals.     

Smelling more or less: Investigating the olfactory experience of the domestic dog

The performance of tracking dogs and drug-, disease-, and explosives-detection dogs is a testament to trained dogs’ olfactory acuity. The olfactory experience of an untrained dog, by contrast, has not been well documented. In the current research we begin to remedy that by testing untrained pet dogs’ olfactory perception of quantity. While previous research found that dogs could discriminate visible quantities of more or less food (Prato-Previde, Marshall-Pescini, & Valsecchi, 2008), our results find that, by contrast, companion dogs do not reliably discriminate quantities when the food can be smelled but not seen. Sixty-one percent of dogs (39 of 64), given a choice between closed plates with one and five morsels of food, approached plates with the larger quantity: not significantly more than approached plates with the lesser quantity (binomial, p = .169). We did find that during dogs’ initial investigation of both food amounts, subjects gave more attention to the plate containing the larger quantity (binomial, p < 0.001). In a second condition, we replicated, with closed plates, Prato-Previde et al.’s (2008) finding that owner interest in a plate holding a lesser quantity of food reliably leads dogs to approach that plate (binomial, p < 0.001). Though research has demonstrated dogs’ preference for a larger amount of food ( Ward & Smuts, 2007), in a third condition testing the effect of adding a strong odor to a visibly larger food quantity, we found that the addition of odor often reversed that preference (44/69 dogs; p < .03). Finally, we consider the methodological implications of this work on future dog cognition studies.