From semantics to syntax and back again: argument structure in the third year of life

An essential part of the human capacity for language is the ability to link conceptual or semantic representations with syntactic representations. On the basis of data from spontaneous production, suggested that young children acquire such links on a verb-by-verb basis, with little in the way of a general understanding of linguistic argument structure. Here, we suggest that a receptive understanding of argument structure--including principles linking syntax and conceptual/semantic structure--appears earlier. In a forced-choice pointing task we have shown that toddlers in the third year of life can map a single scene (involving a novel causative action paired with a novel verb) onto two distinct syntactic frames (transitive and intransitive). This suggests that even before toddlers begin generalizing argument structure in their own speech, they have some representation of conceptual/semantic categories, syntactic categories, and a system that links the two.     

The effects of providing access to stimuli following choice making during vocal preference assessments

Two variations of a vocal paired-stimulus preference assessment were evaluated to determine whether the verbal reports of preference, given by individuals with developmental disabilities when no access to the activity was given, matched their verbal reports when access to the activity was given contingent on their choice. The results indicated different outcomes between the two methods for 6 of the 7 participants. Subsequent reinforcer assessments, conducted for 2 participants, showed that activities identified in the preference assessments that provided access contingent on selection resulted in more responding than did activities identified in the preference assessment that did not include access to items following their selection.     

An evaluation of the value of choice with preschool children

The current study examined the reinforcing effects of choosing among alternatives in a four-part evaluation. In the first study, initial-link responses in a concurrent-chains arrangement resulted in access to terminal links in which the completion of an academic task resulted in (a) the choice of a reinforcer (choice), (b) the delivery of an identical reinforcer (no choice), or (c) no material reinforcer (control). Three patterns of responding emerged: persistent preference for choice (3 participants); initial preference for choice, which did not persist (2 participants); and preference for no choice (1 participant). Additional evaluations determined if preference for choice could be enhanced (Study 2) or established (Study 3) by including more stimuli from which to choose. Choice-link selections systematically increased for all participants when more items were available from which to choose. Study 4 identified the precise value of the opportunity to choose by progressively increasing the response requirement during the choice terminal links for 3 children and determining the point at which these children stopped selecting the choice link. All children continued to select the choice link even when the work required in the choice link was much greater than that arranged in the no-choice link.     

The generalized matching law in elite sport competition: football play calling as operant choice

A mathematical model of operant choice, the generalized matching law was used to analyze play-calling data from the 2004 National Football League season. In all analyses, the relative ratio of passing to rushing plays was examined as a function of the relative ratio of reinforcement, defined as yards gained, from passing versus rushing. Different analyses focused on season-aggregate data for the league as a whole, game-by-game data for the league as a whole, and game-by-game data for individual teams. In all analyses except those for a few individual teams, the generalized matching law accounted for a majority of variance in play calling. The typical play-calling pattern reflected undermatching (suggesting imperfect sensitivity of play calling to yardage-gained reinforcers) and a bias for calling rushing plays. Bias was found to be a function of both the relative risk of turnovers and the relative variability in yards gained associated with passing versus rushing plays. The external validity of the matching analyses was supported by significant correlations between parameters of the generalized matching law and team success on offense and season winning percentage. These results illustrate the broad applicability of the generalized matching law to problems outside of the laboratory.     

Rapid acquisition in concurrent chains: evidence for a decision model

Pigeons' choice in concurrent chains can adapt to rapidly changing contingencies. Grace, Bragason, and McLean (2003) found that relative initial-link response rate was sensitive to the immediacy ratio in the current session when one of the terminal-link fixed-interval schedules was changed daily according to a pseudorandom binary sequence (e.g., Schofield & Davison, 1997). The present experiment tested whether the degree of variation in delays across sessions had any effect on acquisition rate in Grace et al.'s (2003) rapid-acquisition procedure. In one condition ("minimal variation"), the left terminal link was always fixed-interval 8 s and the right terminal link was either fixed-interval 4 s or fixed-interval 16 s. In the other condition ("maximal variation"), a unique pair of fixed-interval values was used in each session. Responding was sensitive to the current-session immediacy ratio in both conditions, but across subjects there was no systematic difference in sensitivity. These results challenge the view that initial-link responding in the rapid-acquisition procedure is determined by changes in the learned value of the terminal-link stimuli, and suggests instead that a process resembling categorical discrimination may control performance. A decision model based on the assumption that delays are categorized as short or long relative to the history of delays provided a good account of the data and shows promise in being able to explain other choice phenomena.     

Pulling out the intentional structure of action: the relation between action processing and action production in infancy

Adults and children readily construct action representations organized with respect to an ultimate goal. These representations allow one to predict the consequences of action, interpret and describe actions, and categorize action sequences. In this paper, we explore the ontogeny of hierarchically organized action representations, and its relation to infants' ability to produce similar sequences. To do so, we examine infants' perception and performance of a means-end sequence: pulling a cloth to retrieve a toy. Using a visual habituation paradigm, we demonstrate that 12-month-old infants understand that the initial step of the cloth-pulling sequence is directed toward the ultimate goal of attaining the toy, and use their knowledge of the causal constraints of the sequence to make this goal attribution. Ten-month-olds, however, appear transitional with respect to this understanding: their ability to identify the goal of the cloth-pulling sequence is related to their own ability to planfully solve a similar sequence. These findings are consistent with a burgeoning body of literature suggesting an intimate link between action production and perception, and suggest that this link is in place by at least 10 months of age.     

Visual arguments

Three experiments investigated the use of verb argument structure by tracking participants' eye movements across a set of related pictures as they listened to sentences. The assumption was that listeners would naturally look at relevant pictures as they were mentioned or implied. The primary hypothesis was that a verb would implicitly introduce relevant entities (linguistic arguments) that had not yet been mentioned, and thus a picture corresponding to such an entity would draw anticipatory looks. For example, upon hearing ...mother suggested..., participants would look at a potential recipient of the suggestion. The only explicit task was responding to comprehension questions. Experiments 1 and 2 manipulated both the argument structure of the verb and the typicality/co-occurrence frequency of the target argument/adjunct, in order to distinguish between anticipatory looks to arguments specifically and anticipatory looks to pictures that were strongly associated with the verb, but did not have the linguistic status of argument. Experiment 3 manipulated argument status alone. In Experiments 1 and 3, there were more anticipatory looks to potential arguments than to potential adjuncts, beginning about 500 ms after the acoustic onset of the verb. Experiment 2 revealed a main effect of typicality. These findings indicate that both real world knowledge and argument structure guide visual attention within this paradigm, but that argument structure has a privileged status in focusing listener attention on relevant aspects of a visual scene.     

On muthén’s maximum likelihood for two-level covariance structure models

Data in social and behavioral sciences are often hierarchically organized. Special statistical procedures that take into account the dependence of such observations have been developed. Among procedures for 2-level covariance structure analysis, Muthén’s maximum likelihood (MUML) has the advantage of easier computation and faster convergence. When data are balanced, MUML is equivalent to the maximum likelihood procedure. Simulation results in the literature endorse the MUML procedure also for unbalanced data. This paper studies the analytical properties of the MUML procedure in general. The results indicate that the MUML procedure leads to correct model inference asymptotically when level-2 sample size goes to infinity and the coefficient of variation of the level-1 sample sizes goes to zero. The study clearly identifies the impact of level-1 and level-2 sample sizes on the standard errors and test statistic of the MUML procedure. Analytical results explain previous simulation results and will guide the design or data collection for the future applications of MUML.This research was supported by NSF Grant DMS04-37167.We thank Dr.Bengt Muthén for providing key references. We are also grateful to three expert reviewers for their constructive comments that have led the paper to an improvement over the previous version.This revised article was published online in August 2005 with the PDF paginated correctly.     

Decreasing Psychiatric Symptoms by Increasing Choice in Services for Adults with Histories of Homelessness

Despite the increase in consumer-driven interventions for homeless and mentally ill individuals, there is little evidence that these programs enhance psychological outcomes. This study followed 197 homeless and mentally ill adults who were randomized into one of two conditions: a consumer-driven “Housing First” program or “treatment as usual” requiring psychiatric treatment and sobriety before housing. Proportion of time homeless, perceived choice, mastery, and psychiatric symptoms were measured at six time points. Results indicate a direct relationship between Housing First and decreased homelessness and increased perceived choice; the effect of choice on psychiatric symptoms was partially mediated by mastery. The strong and inverse relationship between perceived choice and psychiatric symptoms supports expansion of programs that increase consumer choice, thereby enhancing mastery and decreasing psychiatric symptoms.     

The Atomistic Self versus the Holistic Self in Structural Relation to the Other

I argue that meaning or significanceper se, along with the capacity to be conscious thereof, and the values, motives and aspirations, etc. central to the constitution of our intrinsic personal identities, arise, as indeed do our extrinsic social identities, and our very self-consciousness as such, from socio-cultural structures and relations to others. However, so far from our identities and behavior therefore being determined, I argue that the capacity for critical reflection and evaluation emerge from these same structural relations, the more complex and quintessentially human aspects of our behavior being explained not in terms of responses to stimuli but as choices reflecting our evaluation of meaningful or significant alternatives. Finally I provide theoretical grounds for accepting the existence of other subjects and give a holistic, as opposed to a dialectical, account of the way individuals may challenge and change the very socio-cultural ways of relating to and interacting with others so central to constituting their capacities and identities.