MULTIPLE TREATMENT INTERFERENCE IN THE ALTERNATING TREATMENTS DESIGN AS A FUNCTION OF THE INTERCOMPONENT INTERVAL LENGTH

In experimental designs requiring the administration of more than one treatment to the same subject(s), the effect of one treatment may be influenced by the effect of another treatment (Campbell & Stanley, 1963), a phenomenon known as multiple treatment interference. We conducted two studies in which multiple treatment interference in an alternating treatments design was shown to be a function of the length of the intercomponent interval (ICI) separating treatment conditions. In the first study, we evaluated the effects of four different treatments on the mouthing of a severely retarded boy. Under a 1-min ICI no consistent differential responding to treatment was obtained. Differential responding emerged when the ICI was increased from 1 min to 120 min, thus suggesting multiple treatment interference in the lack of differential responding under a 1-min changeover interval. Functional control of the nondifferential and differential responding as a function of the ICI length was replicated in a reversal phase. In the second study, we compared two treatment procedures for the disruptive noncompliant behavior of a moderately retarded boy. Multiple treatment interference (i.e., the lack of differential responding) occurred with the 1-min intercomponent interval. An increase to a 120-min ICI again resulted in differential responding. A replication of multiple treatment interference by a reversal to a short interval phase was not achieved in the second subject. Results of this study support much of the basic literature on discrimination and multiple treatment interference. Major findings of this study are twofold: Multiple treatment interference can depend on the length of the changeover interval between treatments and multiple treatment interference can take the form of a lack of differential responding to various treatments. Implications for future research are discussed.     

Amount consumed varies as a function of feeder design.

Studies of pigeon behavior in which magazine-cycle duration is varied suggest that many researchers assume that feeders of different designs dispense food at roughly the same rate. However, Epstein (1981) showed that, with a commonly used feeder, the amount of grain a pigeon consumes is a negatively accelerated function of magazine-cycle duration. The present experiment shows that, with a different commonly used feeder, amount consumed is roughly a linear function of magazine-cycle duration. At a duration of 60 seconds, the second feeder dispenses roughly 10 times as much food as the first. Thus, reports of studies in which magazine-cycle duration is varied should identify the design of the feeder employed, and in some cases, authors should consider determining the feeding functions for those feeders.     

On more powerful tests of judge agreement with a known standard

To establish the existence of his abilities, a judge is given the task of classifying each ofN=rs subjects into one ofr known categories, each containings of the subjects. An incomplete design is proposed whereby the judge is presented withb groups, each one containingn=rs/b<r subjects. Then different categories corresponding to members of the group are known. Using the total number of correct classifications, this method of grouping is compared to that in which the group size is equal to the number of categories. The incomplete grouping is shown to yield a more powerful test for discriminating between the null hypothesis that the judge is guessing the classifications and the alternative hypothesis that he has some definite abilities. The incomplete design is found to be most effective (powerful) when the number of subjects in a group is limited to two or three.The author is grateful for the suggestions of the referees and the editor, which greatly improved the paper.     

Comparison of Scoring Criteria for Clock Drawing Test

This study compared clock drawings by 42 medically hospitalized patients with a mean age of 51.9 (SD = 10.1) years, using four sets of published scoring criteria to determine comparability of classification and to assess validity by comparison to other measures of cognitive functioning. We found impairment in 20 of 42 cases using the criteria of Mendez et al. (1992); 11 of 42 cases by Sunderland et al. (1989); 9 of 42 cases with Freedman et al. (1994); and 8 of 42 cases according to Rouleau et al. (1992). Kappa coefficients of impairment status between sets of scoring criteria ranged from .41 to .86. Pearson correlations of raw scores between schemes ranged from .72 to .94. All except Sunderland et al. were significantly correlated with the Standardized Mini-Mental State Examination. All correlated significantly with the Wechsler Adult Intelligence Scale–Revised Block Design; however, only Mendez et al. correlated significantly with the Neurobehavioral Cognitive Status Examination. On the basis of these results and our experience, we recommend using the Freedman scoring scheme.     

How Artists Create: An Empirical Study of MFA Painting Students

This paper reports on an interview study with MFA students in two different full‐time MFA degree programs in painting. The interviews were conducted as part of two ethnographic studies, each one academic year in length, of art and design schools at two U.S. universities. The goal was to explore the extended process whereby MFA student artists, in the second and final year of their degree program, create the works to be displayed in their public graduation exhibition. Using a grounded theory approach, an emergent theory was developed from the interviews, with additional information provided by studio observations and analyses of the graduation exhibitions and the accompanying written theses. This emergent theory describes the artistic creative process to be wandering, unpredictable, non‐linear, and embedded in the physical act of generating work. There is no evidence that either moments of insight, or the attempt to be original, play a role in their creative process. This emergent theory is compared with theories of the creative process by creativity researchers, and with theories of the design process proposed by design studies researchers.     

Introducing dental students to reflective practice: a dental educator’s reflections

There is growing consensus that being reflective and developing reflective practice is an important part of becoming a healthcare professional, adding to and enhancing our everyday professional values, knowledge and skills. For dentists, reflective practice is an essential part of dental training and professional development with dental undergraduate curricula creating and scaffolding opportunities for students to be reflective and develop reflective writing skills. This article describes the introduction of a reflective portfolio to the undergraduate Bachelor of Dental Science (BDS) programme at the University of Bristol. This will be followed by the author sharing some personal reflections, as the faculty member overseeing the assessment of these reflective portfolios, on the first year of this initiative. Lessons learned from the exercise as well as areas for future work and improvement will also be mentioned.     

Effects of viewing time,fixations, and viewing strategies on visual memory for briefly presented natural objects

We investigated the impact of viewing time and fixations on visual memory for briefly presented natural objects. Participants saw a display of eight natural objects arranged in a circle and used a partial report procedure to assign one object to the position it previously occupied during stimulus presentation. At the longest viewing time of 7,000 ms or 10 fixations, memory performance was significantly higher than at the shorter times. This increase was accompanied by a primacy effect, suggesting a contribution of another memory component—for example, visual long-term memory (VLTM). We found a very limited beneficial effect of fixations on objects; fixated objects were only remembered better at the shortest viewing times. Our results revealed an intriguing difference between the use of a blocked versus an interleaved experimental design. When trial length was predictable, in the blocked design, target fixation durations increased with longer viewing times. When trial length was unpredictable, fixation durations stayed the same for all viewing lengths. Memory performance was not affected by this design manipulation, thus also supporting the idea that the number and duration of fixations are not closely coupled to memory performance.     

产品设计领域的消费者审美体验

消费者从产品设计上获得的审美体验会影响他们对产品的感知和购买.审美体验的作用机制涉及神经科学研究、信息处理模型和情感反应过程三部分.具体图形与结构元素、一般化的设计要素、个体因素都会影响消费者对设计的审美体验,而审美体验会进一步通过溢出效应、感染效应和对比效应等方式影响产品性能感知、产品评价和购买意向.未来研究应解决已有研究结果间的矛盾并继续探索美学在消费者行为领域的理论和实践价值.