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161.
This article introduces stories as a link between culture and evolution. It elaborates how the decline of interhuman communication leads to a loss of perception, capability for cooperation, and human intelligence and contributes to the current ecocide. It shows how cybernetics hacked the relationship between evolution and machine development, which brought forth the outlines of man’s current digital transformation and future. It suggests that Lucas Pawlik is still working on a possible sustainable future for humanity that Heinz von Foerster tried to initiate.  相似文献   
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163.
Noncontingent reinforcement (NCR) is typically implemented with extinction (EXT) for destructive behavior reinforced by social consequences and without EXT for destructive behavior reinforced by sensory consequences. Behavioral momentum theory (BMT) predicts that responding will be more persistent, and treatment relapse in the form of response resurgence more likely, when NCR is implemented without EXT due to the greater overall rate of reinforcement associated with this intervention. We used an analogue arrangement to test these predictions of BMT by comparing NCR implemented with and without EXT. For two of three participants, we observed more immediate reductions in responding during NCR without EXT. However, for all participants, NCR without EXT produced greater resurgence than NCR with EXT when we discontinued all reinforcers during an EXT Only phase, although there was variability in response patterns across and within participants. Implications for treatment of destructive behavior using NCR are discussed.  相似文献   
164.
Extended pausing during discriminable transitions from rich‐to‐lean conditions can be viewed as escape (i.e., rich‐to‐lean transitions function aversively). In the current experiments, pigeons’ key pecking was maintained by a multiple fixed‐ratio fixed‐ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition‐specific stimulus used in the multiple schedule to a mixed‐schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2). Overall, escape was under joint control of past and upcoming reinforcer magnitudes, such that responses on the escape key were most likely during rich‐to‐lean transitions, and second‐most likely during lean‐to‐lean transitions. Even though pigeons pecked the escape key, they paused before doing so, and the latency to begin the fixed ratio (i.e., the pause) remained extended during rich‐to‐lean transitions. These findings suggest that although the stimulus associated with rich‐to‐lean transitions functioned aversively, pausing is more than simply escape responding from the stimulus.  相似文献   
165.
The purpose of this study was to identify the detailed mechanism how the maximum throwing arm endpoint velocity is determined by the muscular torques and non-muscular interactive torques from the perspective of the dynamic coupling among the trunk, thorax and throwing and non-throwing arm segments. The pitching movements of ten male collegiate baseball pitchers were measured by a three-dimensional motion capture system. Using the induced-segmental velocity analysis (IVA) developed in this study, the maximum fingertip velocity of the throwing arm (MFV) was decomposed into each contribution of the muscular torques, passive motion-dependent torques due to gyroscopic moment, Coriolis force and centrifugal force, and other interactive torque components. The results showed that MFV (31.6 ± 1.7 m/s) was mainly attributed to two different mechanisms. The first is the passive motion-dependent effect on increasing the angular velocities of three joints (thorax rotation, elbow extension and wrist flexion). The second is the muscular torque effect of the shoulder internal rotation (IR) torque on generating IR angular velocity. In particular, the centrifugal force-induced elbow extension motion, which was the greatest contributor among individual joint contributions, was caused primarily by the angular velocity-dependent forces associated with the humerus, thorax, and trunk rotations. Our study also found that a compensatory mechanism was achieved by the negative and positive contributions of the muscular torque components. The current IVA is helpful to understand how the rapid throwing arm movement is determined by the dynamic coupling mechanism.  相似文献   
166.
Higher-order latent trait models for cognitive diagnosis   总被引:9,自引:0,他引:9  
Higher-order latent traits are proposed for specifying the joint distribution of binary attributes in models for cognitive diagnosis. This approach results in a parsimonious model for the joint distribution of a high-dimensional attribute vector that is natural in many situations when specific cognitive information is sought but a less informative item response model would be a reasonable alternative. This approach stems from viewing the attributes as the specific knowledge required for examination performance, and modeling these attributes as arising from a broadly-defined latent trait resembling theϑ of item response models. In this way a relatively simple model for the joint distribution of the attributes results, which is based on a plausible model for the relationship between general aptitude and specific knowledge. Markov chain Monte Carlo algorithms for parameter estimation are given for selected response distributions, and simulation results are presented to examine the performance of the algorithm as well as the sensitivity of classification to model misspecification. An analysis of fraction subtraction data is provided as an example. This research was funded by National Institute of Health grant R01 CA81068. We would like to thank William Stout and Sarah Hartz for many useful discussions, three anonymous reviewers for helpful comments and suggestions, and Kikumi Tatsuoka and Curtis Tatsuoka for generously sharing data.  相似文献   
167.
The changing natures of both work and the lives of the U.S. workforce have created an array of challenges for organizations attempting to foster work engagement. To accommodate the work and family needs of an increasingly diverse workforce, many firms are offering flexible work solutions to employees. However, the distribution of these types of organizational resources is unequal, with workers in lower-wage hourly jobs having the least access to any form of flexibility. The purpose of this paper is to examine the relationship of schedule control, as a form of flexible work practice, and work engagement among workers employed in hourly retail jobs. Authors tested a model whereby the relationship between schedule control and work engagement is mediated by schedule satisfaction and perceived supervisor support. A sample of 1343 full-time hourly retail workers was used to address the study's purpose. Hypothesized relationships were fully or partially supported. Implications for research and practice are discussed.  相似文献   
168.
We evaluated the effects of fixed-interval (FI), fixed-time (FT), and conjoint (combined) FI FT reinforcement schedules on the responding of 3 adults who had been diagnosed with schizophrenia. Responding on vocational tasks decreased for 2 of 3 participants under FT alone relative to FI alone. Responding under FI FT resulted in response persistence for 2 of 3 participants. Results have implications for the maintenance of desirable behavior, as well as for situations in which FT treatment has been implemented for problem behavior and problem behavior is nevertheless reinforced by caregivers.  相似文献   
169.
A literature search identified 17 articles reporting data on 34 subjects who engaged in precursors to severe problem behavior, which we examined to identify topographical and functional characteristics. Unintelligible vocalization was the most common precursor to aggression (27%) and property destruction (29%), whereas self- or nondirected movement was the most common precursor to SIB (32%). Unintelligible vocalization and object-directed movement were the most common precursors to behavior maintained by social-positive reinforcement (27% each), and unintelligible vocalization was the most common precursor to behavior maintained by social-negative reinforcement (29%). Only one precursor was reported for behavior maintained by automatic reinforcement.  相似文献   
170.
Research has not systematically assessed and validated preferences for staff in adults with developmental disabilities. Three adults with developmental disabilities (aged 32 to 43 years) identified preferred and nonpreferred staff using verbal and pictorial preference assessments. During break-point analyses with progressive-ratio schedules, all 3 had higher break points when working for positive social interaction with their preferred staff mamber than with their nonpreferred staff member.  相似文献   
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