共查询到20条相似文献，搜索用时 46 毫秒
1.
Jacky Emmerton 《Learning & behavior》1998,26(3):243-256
Two experiments are described in which pigeons were trained in a simultaneous conditioning procedure to discriminate small arrays of dots that differed in numerosity. The birds successfully learned to choose the array of each pair that contained fewer dots when these choices were reinforced and choices of the array with more dots led to timeout. For the majority of numerosity values tested, discrimination performance for a fixed S+ value was better when the numerical difference between S+ and S-values was larger rather than smaller. This effect was seen in the first experiment when the numerical difference value was shifted between training trials and novel test trials. In the second experiment, too, performance level depended on the size of the numerosity difference when the birds were concurrently trained with two difference values that varied across trials within sessions. However, discrimination accuracy was influenced secondarily by variations in the density, or interdot spacing, of the stimulus arrays. In order to explain the latter finding, it is suggested that a tendency to “scan” a lowdensity array incompletely might alter the probability of accepting it as the smaller numerosity (S+) stimulus. This would increase error rates with S? arrays in which the dots are more widely spaced. 相似文献
2.
Delamater AR 《Learning & behavior》2011,39(3):259-270
Two experiments with thirsty rats explored the harmful effects of non-reinforced exposures to a flavor cue in the control
by sensory-specific flavor–sucrose associations in a conditioned flavor preference paradigm. Experiment 1 demonstrated that rats learned to prefer a flavor cue that was consistently paired with sucrose over one that was paired
with sucrose the same number of times but was also presented without sucrose on other occasions. However, rats for which sucrose
was devalued following the conditioning phase preferred the partially reinforced flavor cue over the consistently reinforced
flavor, suggesting that non-reinforcement weakened the ability of that flavor cue to evoke a specific representation of sucrose
during the preference test. Experiment 2 demonstrated comparable effects of non-reinforcement in a latent inhibition procedure, although relatively more non-reinforced
pre exposures to the flavor, in conjunction with fewer flavor–sucrose pairings, were required to see the effect. Together,
the results suggest, as is often found with more traditional learning paradigms, that non-reinforcement of a flavor cue has
deleterious effects on preference learning and/or performance. 相似文献
3.
Terry W. Belke 《Learning & behavior》2000,28(4):332-343
Previous research showed that sucrose and wheel-running reinforcement of leverpressing generate different response rate asymptotes. To investigate the basis of this difference, the present study assessed the role of inhibitory after-effects and excitatory stimulus effects on measures of responding in rats exposed to fixed-interval schedules that randomly produced either sucrose or wheel-running reinforcers. Different discriminative stimuli were associated with each reinforcer type. Inhibitory aftereffects and excitatory stimulus effects were assessed by the pattern of postreinforcement pauses and local response rates across the four different combinations of previous and upcoming reinforcer types: wheel-wheel, wheel-sucrose, sucrose-wheel, and sucrose-sucrose. Results showed that, regardless of the prior type of reinforcer, response rates were higher and pauses were shorter in the presence of a stimulus signaling sucrose reinforcement. This suggests that differences in response rate asymptotes generated by these qualitatively different reinforcers may have more to do with differences in excitatory stimulus effects than with inhibitory after-effects. 相似文献
4.
In two experiments involving present/absent sample matching, we tested whether the visual stimuli or differential sample behavior served as the basis for comparison choice. In both experiments, one group (FR/DRO) was required to peck the present sample and to refrain from pecking the absent sample (as typically occurs with fixed duration present/absent samples), and the other group (FR/FR) was required to peck both samples. In Experiment 1, the samples were a black dot on a white field (present) and the white field alone (absent). In Experiment 2, the samples were a yellow hue (present) and a dark response key (absent). In both experiments, divergent retention functions were found only for the FR/DRO group. These results suggest that, in nonhedonic present/absent sample matching, it is the behavior directed toward the present sample, rather than the visual stimulus itself, that serves as the basis for comparison choice. 相似文献
5.
Yuyuan Wang 《美中教育评论》2005,2(1):11-17,50
In order to help the selection and training of teachers for kindergartens, a scale for diagnosis of the special psychological predispositions needed for kindergarten teachers has been developed. It consists of 130 items derived from a personality test and an ability test.
By the use of stratified sampling strategy, 660 teachers from different kindergartens in Beijing were chosen to form a sample group in its development. The result of the test was displayed in the form of T-score and percentile respectively. After several times of practice, its reliability and validity have been verified. 相似文献
6.
Mehmet Karakas 《Journal of Science Education and Technology》2009,18(2):101-119
Study provides qualitative analysis of data that answers the following research question: how college science faculty teach science and NOS and incorporate aspects of NOS and the history of science into their undergraduate courses? Study concentrates on four cases and more specifically on three introductory science classes and on four instructors who taught those courses. These instructors were chosen as case studies to explore in greater detail what occurs inside introductory science courses in one particular higher institution in the Northeastern United States. Participants’ teaching styles are presented through a combined and detailed presentation of interview data and classroom observations supported with examples from their classroom activities. Constant comparative approach was used in the process of organizing and analyzing data. Findings revealed that participants preferred to use the traditional teacher-centered lecturing as their teaching style and whose main concern was to cover more content, develop the problem solving skills of their students, and who wanted to teach the fundamental principles of their subjects without paying special importance to the NOS aspects. The study also revealed that other variables of teaching science, such as large class size, lack of management and organizational skills, teaching experience, and instructors’ concerns for students’ abilities and motivation are more important for these scientists then teaching for understanding of NOS. 相似文献
7.
崔叶盛 《中学生英语读写(高中版)》2002,(9)
Charlie Chaplin(查理·卓别林)broke into show business at age fivebecause his mother,a music-hall performer,lost her voice during theperformance and had to leave the stage,and Charlie went on and sang a 相似文献
8.
卢德明 《黎明职业大学学报》2005,(3)
Inlanguage practice,vaguenessisindeed of greatpragmatic value and vitality,thus,with many prepara-tionsin semantic area,I will attempt to analyze vaguelanguage fromthe perspective of pragmatics.This pa-per will deal withthe pragmatic functions of vague lan-guage and because of thelimitation of space,it will fo-cus onthose in daily communication.1.Theoretical Grounds for Pragmatic Func-tions of Vague LanguageWu Shixiong(1996)assumes that“the fuzzinessof language arises fromthe process of hu… 相似文献
9.
FOR THE GEO一TEEHNIEAL DESI，PARAMETERS OF 5011，EOMPARISON OF SEISMIE RESPONSES BASED ON DIFFERENT THE UNEVEN DISTRIBUTION OF THE DIFFERENT KINDS OF 5011 METHODS TO EVALUATE THE 5011 FUNETIONS.IN ADDITION， AND SAMPLING LOCATIONS DURING EXPLORATION AND I… 相似文献
10.
11.
a number of与the number of两个比较容易混淆的短语，尤其是当它们作主语时，其谓语的单复数形式很容易被弄错。要解开他们之间的疙瘩，其中的奥妙就在下面。 相似文献
12.
《天津大学学报(英文版)》2006,(3)
Vice Chairmen SHAN Ping HU Xiaotang CHEN Jiaxiu CAO Chusheng(aeademieian) GU Peiliang GU Yao HUANG Tian HUO Uxing JIANG Enyong JING Hongyang H Yongdan llU Chan幻un MA Yltai PENG Yigang(acade而cian) SHENJi涵ang(academician) SHU GeqUn SHU Yanlai SUW妞nhua SUN Yan SUN Yugeng TANG ZhiyUan WANG Jingkang(acade而 eian WANG Mingshi WANG Tieeheng WANG Xinying YANG Fenghe YANG Xianjin YANG Zhengfang YAO Jian卿an(acade而eian) YE Shenghua(acade而eian) YU… 相似文献
13.
《小学生作文辅导(作文与阅读版)》2006,(12)
2006年12期这是一场比知识,比脑力的竞赛。我们热情地邀请你和你的伙伴一起走入我们的竞猜天地。你的答案要写在信封的背面寄给我们。贴上赛标,写清你的地址哦!本期竞猜结束的时间为2006年12月31日止1.穿了棉衣为什么会暖和?每当冰天雪地的冬季来临,人们总是穿厚厚的棉衣抵御寒 相似文献
14.
This article reports on a study of six Grade 11 learners’ levels of understanding of concepts related to the function definition and representation. Task-based clinical interviews were used to elicit the learners’ interpretations and reasoning when working with these function-related concepts. Indicators for Action–Process–Object–Schema (APOS) theory conception levels were formulated and used to categorise learners’ written and interview responses into conception levels of understanding of the function concept. According to the South African Curriculum Assessment Policy Statement (CAPS) curriculum, Grade 11 learners are expected to be operating at the object and schema levels after instruction. however, the results indicated that learners were operating at the action and process levels as their understanding was characterised by vague definitions of function-related concepts and memorisation of procedures for translating between symbolic and graphical representations. 相似文献
15.
16.
17.
Characterizations of PSD Fractal of Porous Medium 总被引：1，自引：0，他引：1
Fractalisatermusedtodescribegeometricalobjectsthatareinvariantuponthechangeoflengthscale .Manyfrac talcharactersofscaleinvarianceonporousmediumshavebeeninvestigatedduringthepastdecades[1] .Particle sizedistribution (PSD)isafundamentalpropertyofporousmedi ums.PSDofporousmediumsiscommonlyreportedintermsofthepercentagesofvariousparticle sizeintervalsandhasusuallybeenfoundtoobeypowerscalingofthetype[2 ] N(≥d)∝d-Dp (1)whereN(≥d)isthenumberofparticlediameterlargerthanorequaltod ,andthepow… 相似文献
18.
MichaelLewis 《通化师范学院学报》2004,(3):36-39
In the Lexical Approach (1993),Ⅰ argued that language consisted not of vocabulary and structures,but essentially of different kinds of lexical itemsocially sanctioned independent units of meaning, many of these being mulitiword items,which were un-or ntis-identified in earlier language study.Four major categories of lexical item provide a framework foranalysis. 相似文献
19.
20.
《上海大学学报(英文版)》2005,(6)
Editor-in-ChiefDAI Shi-qiang(戴世强)Deputy Editors-in-ChiefWANGShuo-zhong(王朔中)QIANJin-wu(钱晋武)WANG Hai-jiang(王海江)Invited MembersZHOU Bang-xin(周邦新)LIU Gao-lian(刘高联)WAN Xiao-jing(万晓景)JIANG Er-xiong(蒋尔雄)Johan LIU(刘建影)(Sweden)MA Ou(马欧) (U.S.A.)WANG Tie-jun(王铁军)YOU Xiao-hu(尤肖虎)SHE Zhen-su(佘振苏)QIAN Yue-hong(钱跃)(U.S.A.)Omer Van der Biest(Belgium)MembersCHEN Guo-cheng(陈国呈)CHEN Yu-guang(陈宇光)DAI Shi-qiang(戴世强)DING You-… 相似文献