Toxicosis-based aversions to visual cues in rats: A test of the Testa and Ternes hypothesis

Testa and Ternes have proposed that the degree of spatial contiguity between a cue and a food object is an important determinant of the associability of that cue with toxicosis. We found, in accord with the Testa and Ternes hypothesis, that rats showed more profound illness-based aversions to the visual properties of food objects than to the visual properties of food bins or feeding chambers. This result has implications for the design of experiments undertaken to determine the relative associability of cues in different sensory modalities with toxicosis.     

Explaining the effects of relative time in trace conditioning: A preliminary test of a comparator hypothesis

Scalar expectancy theory (SET) predicts that postacquisition manipulations of background expectancy should alter conditioned performance. An experiment was performed to test the application of this hypothesis to an explanation of the “temporal context” effect in trace conditioning. Pigeons were trained on an inhibitory trace conditioning procedure and then subjected to postacquisition manipulations of background expectancy. Nonreinforced exposure to the training apparatus eliminated conditioned withdrawal, exposure to USs under very long interreinforcer intervals slightly weakened conditioned withdrawal, and home-cage confinement had no effect on conditioned withdrawal. These results are discussed in terms of the predictions of SET and the role of background excitation in conditioned inhibition.     

Object location memory: A direct test of the verbal memory hypothesis

Although the male advantage in traditional spatial abilities is well established, the female advantage in object location memory remains tentative. Object location memory is the only spatial ability that yields a female advantage, leading some to speculate that other factors, such as verbal memory, may solely account for the sex difference. The present experiment directly addressed the role of verbal memory using a novel object location memory task. Results suggest that the direction of the sex difference is context-specific, depending on the nature of the stimuli, and that verbal memory may account for the female bias in object location memory.     

Phonological skills and comprehension failure: A test of the phonological processing deficit hypothesis

Shankweiler and colleagues argue that text comprehensionproblems in young children arise from phonological processingdifficulties. Their work has focused on children with poor wordreading ability. We investigated this hypothesis for children whoexperience comprehension difficulties in the presence of age-appropriate word reading skills. We found that good and poorcomprehenders performed comparably on various measures ofphonological processing and differed on a task that made greaterdemands on working memory, Bradley and Bryant's odd-word-outtask. In a final study, hierarchical regression analyses supportedthis distinction: the odd-word-out task was a strong predictor ofreading comprehension performance even after IQ, vocabulary and single word reading had been controlled for, but a lessmemory-dependent phonological task was not. These studiessupport previous work which indicates that poor comprehenders'problems arise from higher-level processing difficulties.     

Reading and spelling acquisition in two different teaching methods: A test of the independence hypothesis

The development of word reading and word spelling was examined in French speaking children initially instructed either by a phonic or a whole-word method. Second, fourth and sixth graders were administered to reading and spelling tests in which grapho-phonological regularity, frequency, length and lexicality were manipulated. The results showed that in both curricula, reading and spelling acquisition can be characterized by a parallel increase in the use of sub-lexical correspondences and in the reliance on word-specific information. Contrary to a simple view of lexical development according to which the use of analytical knowledge and the use of word-specific knowledge correspond to two different cognitive processes that develop independently from each other, whole-word children did not appear to rely more on whole-word knowledge. On the contrary, and paradoxically, grade 2 whole-word children tended to use analytical correspondences to a greater extent than their peers. In later development, reading matched phonic and whole-word groups did not differ from each other. It is argued that the results support the hypothesis that the acquisition of sub-lexical correspondences constitutes a necessary step in the acquisition of reading and spelling. We conclude that the analytic comparison of different curricula provides a naturalistic tool for the study of the dynamics of development.     

Lifelong education: a test of the accumulation hypothesis

A path model of the lifelong education cycle is developed and estimated, using data relevant to a Swedish cohort of men and the method of linear structural relations analysis. The estimates are used to address the question as to whether adult education, by offsetting differences in educational backgrounds, has reduced the gap in educational attainment between the initially poorly‐educated and well‐educated groups comprising the sample studied. The results show that a cycle of accumulation is in operation, so that the quality of earlier experiences of education predict the quality and amount of educational experiences subsequently gathered. Hence, as the expansion of adult education has served to reinforce inequality of educational attainment, at least for the group of Swedish men studied, the accumulation hypothesis is supported. However, because the stability coefficients found in the model are only of modest size, it is concluded that there is room for interventionist policy designed to influence the social distribution of adult education resources.     

Cognitive biases in the interpretation of autonomic arousal: A test of the construal bias hypothesis

According to Bandura’s construal bias hypothesis, derived from social cognitive theory, persons with the same heightened state of autonomic arousal may experience either pleasant or deleterious emotions depending on the strength of perceived self-efficacy. The current study tested this hypothesis by proposing that college students’ preexisting efficacy beliefs may affect how physiological arousal during exams is construed as a valence of positive emotion. Survey data were collected from 172 students in a statistics course at a large research university in the Midwest. Students provided self-reported intensity of autonomic arousal during previous exams, statistics self-efficacy, and positive affect toward a proximal final exam. The construal bias hypothesis was supported by a significant interaction between autonomic arousal and self-efficacy on the dependent variable positive affect. Results revealed that as autonomic arousal increased, so did the moderating effect of self-efficacy. Specifically, as physiological arousal intensified, students with high or low self-efficacy reported divergent levels of positive emotion. Implications for theory, research, and practice are discussed.     

Classically conditioned tail flexion in rats: CR-contingent modification of US intensity as a test of the preparatory response hypothesis

A classically conditioned tail flexion in rats with a white noise as the conditioned stimulus and a tailshock as the unconditioned stimulus is shown to arise as a result of contingent presentation of the two stimuli rather than from sensitization or pseudoconditioning. After achieving an asymptote for conditioned tail flexion, different groups received response-contingent tail-shock increment, decrement, or omission. None of these treatments appreciably altered the probability of a conditioned response. Evidence is presented demonstrating that the response was sensitive to changes in the relationship between the stimuli and that the subjects could differentiate the various shock levels. The present data are viewed as inconsistent with the preparatory response hypothesis, which posits that classically conditioned behavior depends upon intrinsic reinforcement of components of the conditioned response syndrome. The possibility is discussed that classically conditioned responses observed in the laboratory are often only part of a larger, perhaps more clearly instrumental, set of behaviors that would occur in the unrestrained animal.     

Education and employment status: a test of the strong screening hypothesis in Italy

We apply the comparative techniques originated by Wolpin, K.I. (1977, Education and screening, American Economic Review, 67, 949–958) and Psacharopoulos (1979, On the weak versus the strong version of the screening hypothesis, Economics Letters, 4, 181–185) to discriminate between the ‘weak' and ‘strong' screening hypotheses. Controlling for sample selection, we find evidence for weak but not strong screening in the Italian labour market. [JEL J3, J24, J41]     

Depression and learning disabilities in children: a test of an hypothesis

Performance-Verbal IQ discrepancy scores are compared for 27 depressed and 15 nondepressed children all of whom experienced learning difficulties. Brumbach (1985) reported a significant association between depression and Performance IQ deficits for children with learning difficulties. In contrast to Brumbach's finding, no difference was observed in Performance IQ deficit between depressed and nondepressed children in the current study. Moreover, only 10% of depressed children showed such a deficit. This result differed significantly from Brumbach's findings (34%). Implications of these results are discussed within the context of nascent interest in the relationship between depression and learning disabilities.     

Bridging temporal gaps between CS and US in autoshaping: A test of a local context hypothesis

Recent reports indicate that conditioning to contextual cues importantly modulates the amount of trace conditioning. According to this view, the strength of conditioning to a trace CS should be inversely related to the extent to which other external stimuli already predict US occurrence. An experiment with pigeons in an autoshaping (sign-tracking) preparation examined this proposition. Insertion of a tone in the 12-sec gap between CS and US led to strong CS responding, except for the case in which the tone also overlapped the CS. However, weak CS responding was obtained when the tone filled only the first or last half of the CS-US gap, even though CS and tone did not overlap. These findings are discussed in terms of an explanation of the effects of gap filling based on conditioning to “local” and “general” contextual cues, and in terms of the possible contributions of second-order conditioning.     

Students’ choice of animated pedagogical agents in science learning: A test of the similarity-attraction hypothesis on gender and ethnicity

College students learned about science with a multimedia program. One group (choice or C) chose to learn with or without an animated pedagogical agent (APA) representing a male or female of five different ethnicities. Another group (no-choice or NC) was assigned an APA by the system. All participants in C group chose to learn with APAs and students of color chose significantly more same-ethnicity APAs than White American students. A significant interaction between choice and ethnic similarity factors revealed that group C produced lower retention, transfer, and program ratings when learning with same-ethnicity rather than different-ethnicity APAs. Results support an interference hypothesis for students who choose to learn with same-ethnicity APAs.     

与假说有关的试题归类解析

本文对一些与假说有关的典型例题进行归类解析。     

对评分者信度检验中零假设的更正

我们通常采用Friedman双向秩次方差分析和Kendall和谐系数检验法来进行评分者信度检验.在绝大多数书籍中,此检验的零假设都被设置成"H0m个评分者对n个被评对象的评分是一致的".但是,这一零假设是错误的,本文将列举反例并给出正确假设的理论依据.     

Naming speed deficits in adults with reading disabilities: a test of the double-deficit hypothesis

The present study investigated the persistent nature of naming speed deficits within the context of the double-deficit hypothesis in a university sample of adults with reading disabilities (RD). Twenty-five university students with RD were compared to 28 typically achieving readers on measures of reading skill, phonological processing, and naming speed. The results indicated that both naming speed and phonological processing deficits characterized the RD group. In a regression analysis, neither naming speed nor phonological processing were important variables in explaining comprehension when reading rate was in the model. The results of the present study are mixed at best and are consistent with earlier conclusions that support for the double-deficit hypothesis of dyslexia remains limited.     

Use of the decomposition technique to test the educational screening hypothesis

The principal issue addressed in this article is whether or not education directly creates productivity and earnings as taught by traditional human capital theory. If not, an alternative argument could be that employers use education as a screening device to select employees. Employing the decomposition technique to compare income for self-employed and private sector employees, evidence is presented which rejects the screenist theory.     

毛细管气相色谱法测定阿奇霉素原料药中乙醇残留量

建立了阿奇霉素原料药中乙醇残留量的测定方法.采用气相色谱法,氢火焰离子化检测器(FID),以0.1 mol/L稀盐酸为溶剂,HP-FFAP弹性石英毛细管柱为色谱柱(30 m×0.25 mm,0.25μm),氮气为载气,分流比为60∶1,进样口温度为200℃,检测器温度250℃,柱温采用程序升温.乙醇在0.01%-2%的浓度范围内呈良好的线性关系(r=0.9994),RSD在0.78%-1.83%之间,最小检出限为5.0 ng.     

The role of US novelty in retention interval effects in single-element taste-aversion learning

Retention interval effects are seen in taste-aversion learning when single-element aversions are significantly weaker 24 h after conditioning compared with tests at later intervals. This report contains three experiments which suggest that the source of the increased drinking at the 1-day interval is nonassociative interference produced by the novel conditioning episode. In Experiment 1, a parametric analysis demonstrated that aversion strength increased monotonically over a 30-h period following conditioning, and that by 48 h after conditioning it was stabilized. In Experiment 2, a single US preexposure was used to reduce the novelty of the US prior to conditioning. As a result, animals preexposed to the US had stronger taste aversions than did non-preexposed controls at a 1-day retention interval; however, no differences were seen at a 5-day interval. Experiment 3 investigated whether the counterintuitive outcome of Experiment 2 was due to the summation of environment-illness and taste-illness associations at the 1-day test. The results ruled out the summation argument; the US preexposure did not need to be presented in the conditioning context to strengthen the aversion at the 1-day interval. Collectively, these results suggest that the presentation of a surprising US can interfere with the retrieval of the taste-illness association for a short period after conditioning, and that this contributes to the retention interval effect.     

Sex differences in rats’ stationary exploration as a function of stimulus and environmental novelty

Stationary visual scanning and sniffing of novel stimuli were measured using a head-poke response to supplement existing equivocal data on sex differences in exploration. With a short exposure to a novel apparatus, males and females showed a similar frequency of exploratory bouts, but the bouts were longer in females, showing that the sex difference is independent of a simple activity difference. With longer exposure, the difference was reversed, with males “compensating” for their initially lower level. Following familiarization to the apparatus, the sexes did not differ in exploration of an introduced novel stimulus. These results are consistent with males being more susceptible to inhibitory influences, such as disturbance and extreme novelty. Differences in within-trial changes in the level of exploration of a novel stimulus in novel and familiar environments were also observed.