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111.
采用实时窗口阅读技术,探讨文本阅读中角色目标在情境模型空间维度非线索更新中的作用。实验一结果表明,阅读中。如果文本叙述中的角色在一个目标指引下展开活动.那么可以促进相应空间设置内的物体的更新。实验二考察了不同性质的角色目标在空问信息加工中的作用,结果发现,相对于已经达成的目标,未达成的目标对情境模型空间维度非线索更新的影响更大。  相似文献   
112.
Demri  Stéphane  Orłowska  Ewa 《Studia Logica》1999,62(2):177-200
In this paper a unified framework for dealing with a broad family of propositional multimodal logics is developed. The key tools for presentation of the logics are the notions of closure relation operation and monotonous relation operation. The two classes of logics: FiRe-logics (finitely reducible logics) and LaFiRe-logics (FiRe-logics with local agreement of accessibility relations) are introduced within the proposed framework. Further classes of logics can be handled indirectly by means of suitable translations. It is shown that the logics from these classes have the finite model property with respect to the class of -formulae, i.e. each -formula has a -model iff it has a finite -model. Roughly speaking, a -formula is logically equivalent to a formula in negative normal form without occurrences of modal operators with necessity force. In the proof we introduce a substantial modification of Claudio Cerrato's filtration technique that has been originally designed for graded modal logics. The main core of the proof consists in building adequate restrictions of models while preserving the semantics of the operators used to build terms indexing the modal operators.  相似文献   
113.
为考查观察者公正敏感性对不公正信息加工(注意、解释)的影响,该研究开展了两个实验研究。在实验一中,让被试观看不公正影片剪辑或中性剪辑后,要求他们完成视觉探测任务,判断探测刺激是在不公正词汇还是中性词汇的左边或右边;在实验二中,让被试对一个模糊的暗含不公正意义的影片剪辑中的主角进行公正性评价。结果表明,当被试不公正概念被激活后,观察者公正敏感性高的被试比观察者公正敏感性低的被试对不公正信息的注意加工更集中和更自动,同时他们对模糊的信息解释为更不公正。  相似文献   
114.
One of the main objectives of many empirical studies in the social and behavioral sciences is to assess the causal effect of a treatment or intervention on the occurrence of a certain event. The randomized controlled trial is generally considered the gold standard to evaluate such causal effects. However, for ethical or practical reasons, social scientists are often bound to the use of nonexperimental, observational designs. When the treatment and control group are different with regard to variables that are related to the outcome, this may induce the problem of confounding. A variety of statistical techniques, such as regression, matching, and subclassification, is now available and routinely used to adjust for confounding due to measured variables. However, these techniques are not appropriate for dealing with time-varying confounding, which arises in situations where the treatment or intervention can be received at multiple timepoints. In this article, we explain the use of marginal structural models and inverse probability weighting to control for time-varying confounding in observational studies. We illustrate the approach with an empirical example of grade retention effects on mathematics development throughout primary school.  相似文献   
115.
This study aimed to explore health professionals' views and practice regarding the provision of information about health-protective behaviors (e.g., exercise, alcohol consumption, diet) during genetic consultation for breast cancer. Ten genetic counselors participated in three focus groups, and seven medical specialists were interviewed in a focus group or individually. Data was analyzed using the constant comparative method. Findings suggested that health professionals held differing, often opposing, views about the value of health-protective behaviors for women at increased risk of breast cancer. The content and extent of information provided about health-protective behaviors varied widely, and participants expressed a need to form consensus regarding information provision both within and across clinics. The main barriers to providing information regarding health-protective behaviors included the lack of research evidence regarding the impact of these factors and higher priority of other information need to be provided in the limited consultation time. Participants generally did not consider it their role to promote health-protective behaviors, and were concerned about the psychological impact of providing information about behavioral risk factors during genetic consultations.  相似文献   
116.
We presented bumblebees a spatial memory task similar to that used with other species (e.g., cats, dogs, and pigeons). In some conditions we allowed for presence of scent marks in addition to placing local and global spatial cues in conflict. Bumblebees (Bombus impatiens) were presented an array of artificial flowers within a flight cage, one flower offering reward (S+), while the others were empty (S−). Bees were tested with empty flowers. In Experiment 1, flowers were either moved at the time of testing or not. Bees returned to the flower in the same absolute position of the S+ (the flower-array-independent (FAI) position), even if it was in the wrong position relative to the S− and even when new flower covers prevented the use of possible scent marks. New flower covers (i.e., without possible scent marks) had the effect of lowering the frequency of probing behavior. In Experiment 2, the colony was moved between training and testing. Again, bees chose the flower in the FAI position of the S+, and not the flower that would be chosen using strictly memory for a flight vector. Together, these experiments show that to locate the S+ bees did not rely on scent marks nor the positions of the S−, though the S− were prominent objects close to the goal. Also, bees selected environmental features to remember the position of the S+ instead of relying upon a purely egocentric point of view. Similarities with honeybees and vertebrates are discussed, as well as possible encoding mechanisms.  相似文献   
117.
In several species, the ability to locate a disappearing object is an adaptive component of predatory and social behaviour. In domestic dogs, spatial memory for hidden objects is primarily based on an egocentric frame of reference. We investigated the geometric components of egocentric spatial information used by domestic dogs to locate an object they saw move and disappear. In experiment 1, the distance and the direction between the position of the animal and the hiding location were put in conflict. Results showed that the dogs primarily used the directional information between their own spatial coordinates and the target position. In experiment 2, the accuracy of the dogs in finding a hidden object by using directional information was estimated by manipulating the angular deviation between adjacent hiding locations and the position of the animal. Four angular deviations were tested: 5, 7.5, 10 and 15°. Results showed that the performance of the dogs decreased as a function of the angular deviations but it clearly remained well above chance, revealing that the representation of the dogs for direction is precise. In the discussion, we examine how and why domestic dogs determine the direction in which they saw an object disappear.  相似文献   
118.
The present experiments explored the resolution of activated background information in text comprehension. In Experiment 1, participants read passages that contained an elaboration section that was either consistent or qualified (inconsistent but then corrected to be consistent) with respect to the subsequently presented target sentence (see O'Brien et al., 1998). However, the experiment used two target sentences, and several filler sentences were inserted between the first and second target sentence. The results showed that the reading times for the first target sentence in the qualified elaboration version were significantly longer than those in the consistent elaboration version. These were consistent with O'Brien's study, and further indicated that the basic process captured by the memory-based view appears to generalize to the Chinese reader better than does the here-and-now view. More importantly, the results showed that the reading times for the second target sentence in the qualified elaboration version were as long as those in the consistent elaboration version. These further indicated that the activation of background information not only maintained the coherence of the text, but also allowed for the relevant information to be updated, resulting in a unified information set. When the information was reactivated during ongoing reading, it would be in the form of unified information. In Experiment 2, the first target sentence in each passage from Experiment 1 was converted to a filler sentence, and the second target sentence became the target sentence. The results of Experiment 2 showed that the reading times for the target sentence in the qualified elaboration version were significantly longer than those for the consistent elaboration version. These indicated that the delay between the target sentences and the elaboration section was not responsible for the lack of differences in Experiment 1, and confirmed the conclusion of Experiment 1.  相似文献   
119.
Four boys with autism were taught via echoic prompting and constant prompt delay to mand for answers to questions by saying “I don't know please tell me” (IDKPTM). This intervention resulted in acquisition of the IDKPTM response for all 4 participants and in acquisition of correct answers to most of the previously unknown questions for 2 participants. For 1 participant, tangible reinforcement resulted in increased frequency of correct answers, and direct prompting of correct answers was eventually conducted for the final participant. The IDKPTM response generalized to untargeted unknown questions with 3 participants. Results of person and setting generalization probes varied, but some generalization eventually occurred for all participants following additional training or interspersal of probe trials with training trials.  相似文献   
120.
Results from studies of observing responses have suggested that stimuli maintain observing owing to their special relationship to primary reinforcement (the conditioned-reinforcement hypothesis), and not because they predict the availability and nonavailability of reinforcement (the information hypothesis). The present article first reviews a study that challenges that conclusion and then reports a series of five brief experiments that provide further support for the conditioned-reinforcement view. In Experiments 1 through 3, participants preferred occasional good news (a stimulus correlated with reinforcement) or no news (a stimulus uncorrelated with reinforcement) to occasional bad news (a stimulus negatively correlated with reinforcement). In Experiment 4 bad news was preferred to no news when the absence of stimulus change following a response to the bad-news option was reliably associated with good news. When this association was weakened in Experiment 5 the results were intermediate. The results support the conclusion that information is reinforcing only when it is positive or useful. As required by the conditioned-reinforcement hypothesis, useless information does not maintain observing.  相似文献   
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