Biconditional Rule-Difficulty

1974 ◽  
Vol 35 (2) ◽  
pp. 955-962
Author(s):  
Tom Ciborowski
Keyword(s):  
Present Experiment ◽  
Strong Support ◽  
Empirical Support ◽  
Rule Learning ◽  
Learning Problems ◽  
Direct Test ◽  
College Age ◽  
Arbitrary Assumption

Three different groups of college age Ss received biconditional rule-learning problems that were altered in such a way as to permit a direct test of an unpublished model of Ss' behavior proposed by C. K. Sawyer and P. Johnson and substantially extended by Salatas and Bourne (1972). The present experiment obtained strong support for the model and evidence to support the widely reported suggestion that the principal difficulty with a biconditional rule is that S must learn to classify together two groups of elements that share no elements in common. The major outcome of the experiment was that strong empirical support was obtained for a useful but arbitrary assumption by Salatas and Bourne concerning a metric for evaluating biconditional rule-difficulty.

scholarly journals Region-specific elevations of glutamate + glutamine correlate with the sensory symptoms of autism spectrum disorders

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jason L. He ◽  
Georg Oeltzschner ◽  
Mark Mikkelsen ◽  
Alyssa Deronda ◽  
Ashley D. Harris ◽  
...  
Keyword(s):  
Autism Spectrum Disorders ◽  
Strong Support ◽  
Empirical Support ◽  
Brain Regions ◽  
Autism Spectrum ◽  
Resonance Spectroscopy ◽  
Primary Sensorimotor Cortex ◽  
Spectrum Disorders ◽  
Inhibitory Signaling

AbstractIndividuals on the autism spectrum are often reported as being hyper- and/or hyporeactive to sensory input. These sensory symptoms were one of the key observations that led to the development of the altered excitation-inhibition (E-I) model of autism, which posits that an increase ratio of excitatory to inhibitory signaling may explain certain phenotypical expressions of autism spectrum disorders (ASD). While there has been strong support for the altered E-I model of autism, much of the evidence has come from animal models. With regard to in-vivo human studies, evidence for altered E-I balance in ASD come from studies adopting magnetic resonance spectroscopy (MRS). Spectral-edited MRS can be used to provide measures of the levels of GABA + (GABA + macromolecules) and Glx (glutamate + glutamine) in specific brain regions as proxy markers of inhibition and excitation respectively. In the current study, we found region-specific elevations of Glx in the primary sensorimotor cortex (SM1) in ASD. There were no group differences of GABA+ in either the SM1 or thalamus. Higher levels of Glx were associated with more parent reported difficulties of sensory hyper- and hyporeactivity, as well as reduced feed-forward inhibition during tactile perception in children with ASD. Critically, the finding of elevated Glx provides strong empirical support for increased excitation in ASD. Our results also provide a clear link between Glx and the sensory symptoms of ASD at both behavioral and perceptual levels.

Application of a Modified Internet Shopper Lifestyle Scale to Taiwanese College-Age Sporting Goods Consumers

2014 ◽  
Vol 42 (8) ◽  
pp. 1245-1256 ◽  
Author(s):  
Weisheng Chiu ◽  
Hyung-Hoon Kim ◽  
Young-Ae Lee ◽  
Doyeon Won
Keyword(s):  
Cluster Analysis ◽  
University Students ◽  
Factor Model ◽  
Empirical Support ◽  
Marketing Strategies ◽  
Convenience Sample ◽  
College Age ◽  
Sporting Goods

We investigated segments of college-age online sporting goods consumers based on the dimensions of a modified Internet shopper lifestyle scale. Participants comprised a convenience sample of 1,187 Taiwanese university students who were online sporting goods consumers. The results confirmed the dimensionality of the modified scale and provided strong empirical support for a 6-factor model comprising Internet convenience, Internet distrust, Internet window shopping, Internet logistics, bricks-and-mortar, and Internet offers. Next, using cluster analysis, we identified 3 groups of college-age sporting goods consumers, whom we labeled shopping lovers, tentative shoppers, and suspicious shoppers. The characteristics of each segment were explored to aid in understanding online sporting goods consumers. These findings provide implications for sporting goods marketers, who can tailor marketing strategies to each segment.

scholarly journals Multispecies coexistence of trees in tropical forests: spatial signals of topographic niche differentiation increase with environmental heterogeneity

2013 ◽  
Vol 280 (1764) ◽  
pp. 20130502 ◽  
Author(s):  
C. Brown ◽  
D. F. R. P. Burslem ◽  
J. B. Illian ◽  
L. Bao ◽  
W. Brockelman ◽  
...  
Keyword(s):  
Spatial Structure ◽  
Environmental Heterogeneity ◽  
Neutral Theory ◽  
Strong Support ◽  
Empirical Support ◽  
Niche Differentiation ◽  
Heterogeneous Environments ◽  
Strong Positive Relationship ◽  
Species Pairs ◽  
Topographic Heterogeneity

Neutral and niche theories give contrasting explanations for the maintenance of tropical tree species diversity. Both have some empirical support, but methods to disentangle their effects have not yet been developed. We applied a statistical measure of spatial structure to data from 14 large tropical forest plots to test a prediction of niche theory that is incompatible with neutral theory: that species in heterogeneous environments should separate out in space according to their niche preferences. We chose plots across a range of topographic heterogeneity, and tested whether pairwise spatial associations among species were more variable in more heterogeneous sites. We found strong support for this prediction, based on a strong positive relationship between variance in the spatial structure of species pairs and topographic heterogeneity across sites. We interpret this pattern as evidence of pervasive niche differentiation, which increases in importance with increasing environmental heterogeneity.

scholarly journals Casting Ballots When Knowing Results

2021 ◽  
pp. 1-19
Author(s):  
Victor Araújo ◽  
Malu A.C. Gatto
Keyword(s):  
Presidential Elections ◽  
Strong Support ◽  
Empirical Support ◽  
Access To Information ◽  
Bandwagon Effect ◽  
It Impacts ◽  
Run Off ◽  
Information Exposure ◽  
Key Factor ◽  
The Impact

Abstract Access to information about candidates' performance has long stood as a key factor shaping voter behaviour, but establishing how it impacts behaviour in real-world settings has remained challenging. In the 2018 Brazilian presidential elections, unpredictable technical glitches caused by the implementation of biometrics as a form of identification led some voters to cast ballots after official tallies started being announced. In addition to providing a source of exogenous variation of information exposure, run-off elections also enable us to distinguish between different mechanisms underlying the impact of information exposure. We find strong support for a vote-switching bandwagon effect: information exposure motivates voters to abandon losing candidates and switch support for the frontrunner – a finding that stands in the second round, when only two candidates compete against each other. These findings provide theoretical nuance and stronger empirical support for the mechanisms underpinning the impact of information exposure on voter behaviour.

The Conceptual Basis for Morpheme Learning Problems in Children With Specific Language Impairment

1994 ◽  
Vol 37 (2) ◽  
pp. 389-398 ◽  
Author(s):  
Phil J. Connell ◽  
C. Addison Stone
Keyword(s):  
Language Impairment ◽  
Specific Language Impairment ◽  
Rule Learning ◽  
Cognitive Domain ◽  
Learning Problems ◽  
Symbol Systems ◽  
Specific Language ◽  
Linguistic Rule ◽  
Visual Tasks ◽  
Nonverbal Ability

Two groups of children were exposed to instances of a nonlinguistic conceptual rule under controlled instructional conditions to determine whether the problems children with specific language impairment (SLI) have learning and accessing language rules extend beyond the language domain into the general cognitive domain. The performance of 20 children with SLI, aged 5:0 to 6:11 (years:months), was compared to that of 20 normally developing children matched for age and nonverbal ability. These children were taught under two instructional conditions that differed only in whether the child was asked to imitate the solution to a conceptual problem after each demonstration (imitation) or merely to observe it (modeling). Contrary to previous findings regarding linguistic rule-learning using auditory or visual symbol systems and similar instructional conditions, no difference was found between the extent of overall learning displayed by the normally developing children and those with SLI. Also, the performance of the children with SLI was not uniquely better under the imitation condition than under modeling, as had been the case with the learning of a novel morpheme in an auditory linguistic task. These results are interpreted as confirming the earlier assumption that the generally lower overall learning rate of the children with SLI on both the auditory and visual tasks reflects a specific linguistic rule-learning difficulty, rather than a general deficiency in rule induction.

scholarly journals Niche construction on Bali: the gods of the countryside

2011 ◽  
Vol 366 (1566) ◽  
pp. 927-934 ◽  
Author(s):  
J. Stephen Lansing ◽  
Karyn M. Fox
Keyword(s):  
Niche Construction ◽  
Strong Support ◽  
Empirical Support ◽  
Local Variation ◽  
Test Case ◽  
Agricultural Policies ◽  
Population Genetic Analysis ◽  
Dual Inheritance Theory ◽  
Biological Phenomena ◽  
Conscious Intention

Human niche construction encompasses both purely biological phenomena, such as the evolution of lactose tolerance, and dual inheritance theory, which investigates the transmission of cultural information. But does niche construction help to explain phenomena in which conscious intention also plays a role? The creation of the engineered landscape of Balinese rice terraces offers a test case. Population genetic analysis and archaeological evidence are used to investigate whether this phenomenon emerged historically from trial and error by generations of farmers, or alternatively was designed by Bali's rulers. In light of strong support for the former hypothesis, two models are developed to explore the emergence of functional structure at both local and global scales. As time goes forward and selected patterns of irrigation schedules are implemented, local variation in rice harvests influences future decisions by the farmers, creating a coupled human–natural system governed by feedback from the environment. This mathematical analysis received a measure of empirical support when government agricultural policies severed the local feedback channels, resulting in the almost instantaneous collapse of rice harvests. The historical process of niche construction may also have included an evolution of religious consciousness, reflected in the beliefs and practices of the water temple cult.

The Disbursement Pattern of Japanese Foreign Aid: A Reappraisal

2009 ◽  
Vol 9 (2) ◽  
pp. 219-248 ◽  
Author(s):  
John P. Tuman ◽  
Jonathan R. Strand ◽  
Craig F. Emmert
Keyword(s):  
Human Rights ◽  
Latin America ◽  
Middle East ◽  
Foreign Aid ◽  
Strong Support ◽  
Empirical Support ◽  
Comprehensive Analysis ◽  
Economic Interests ◽  
Aid Allocation ◽  
Global Study

Three perspectives on the determinants of Japan's official development assistance (ODA) program are often represented as distinct, valid explanations of the aid program. Yet few studies have attempted to simultaneously test the hypotheses generated from all three perspectives in a global study of Japanese aid flows. This study seeks to improve the understanding of the Japanese ODA program by addressing some of the gaps in the existing literature. Providing a comprehensive analysis, the article investigates the effects of different political and economic variables on Japanese aid disbursement in eighty-six countries in Africa, Asia, Latin America, and the Middle East from 1979 to 2002. The findings of the study make several contributions to the literature. First, the results provide strong support for the claim that humanitarian concerns, as measured by poverty and human rights conditions in recipient countries, are important determinants of aid allocation. Second, although much of the previous literature has hypothesized that Japan's aid program seeks to promote Japan's economic interests, little empirical support for this view is found in the present study. Likewise, the disbursement pattern of ODA was associated with only a limited number of US security interests; US economic interests are shown to have no effect on ODA.

Parsing Temporarily Ambiguous Complements

1987 ◽  
Vol 39 (4) ◽  
pp. 657-673 ◽  
Author(s):  
Keith Rayner ◽  
Lyn Frazier
Keyword(s):  
Eye Movement ◽  
Present Experiment ◽  
Reading Time ◽  
Empirical Support ◽  
Reading Task ◽  
Garden Path ◽  
Movement Data ◽  
The Subject ◽  
Per Se ◽  
Attachment Strategy

Holmes, Kennedy and Murray (1987) recently claimed that the empirical support for the Minimal Attachment Strategy of sentence parsing had been weakened by results they reported. They found that reading time for an ambiguous string of words did not decrease when it was preceded by an overt complementizer, which should have disambiguated it. Thus, they suggested that results that we (Frazier and Rayner, 1982) earlier attributed to Minimal Attachment were not due to “garden-path” effects, but rather reflected the extra complexity caused by having to process two sets of clausal relations instead of just one. In the present experiment, we replicated their experiment using eye movement data rather than the subject-paced reading task they used. We found that readers processed Nonminimal Attachment sentences with overt complementizers considerably faster than those without a complementizer. Our results showed that the complexity of Nonminimal Attachment sentences cannot be attributed to their clausal status per se. Differences between the tasks that might contribute to the different pattern of results across the experiments are discussed.

scholarly journals Sparse evidence for selection on phenotypic plasticity in response to temperature

2019 ◽  
Vol 374 (1768) ◽  
pp. 20180185 ◽  
Author(s):  
Pieter A. Arnold ◽  
Adrienne B. Nicotra ◽  
Loeske E. B. Kruuk
Keyword(s):  
Phenotypic Plasticity ◽  
Environmental Change ◽  
Mixed Model ◽  
Meta Analysis ◽  
Strong Support ◽  
Empirical Support ◽  
Mixed Model Approach ◽  
Thermal Plasticity ◽  
Response To Temperature ◽  
Rapid Environmental Change

Phenotypic plasticity is frequently assumed to be an adaptive mechanism by which organisms cope with rapid changes in their environment, such as shifts in temperature regimes owing to climate change. However, despite this adaptive assumption, the nature of selection on plasticity within populations is still poorly documented. Here, we performed a systematic review and meta-analysis of estimates of selection on thermal plasticity. Although there is a large literature on thermal plasticity, we found very few studies that estimated coefficients of selection on measures of plasticity. Those that did do not provide strong support for selection on plasticity, with the majority of estimates of directional selection on plasticity being weak and non-significant, and no evidence for selection on plasticity overall. Although further estimates are clearly needed before general conclusions can be drawn, at present there is not clear empirical support for any assumption that plasticity in response to temperature is under selection. We present a multivariate mixed model approach for robust estimation of selection on plasticity and demonstrate how it can be implemented. Finally, we highlight the need to consider the environments, traits and conditions under which plasticity is (or is not) likely to be under selection, if we are to understand phenotypic responses to rapid environmental change. This article is part of the theme issue ‘The role of plasticity in phenotypic adaptation to rapid environmental change’.

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