An examination of the effect of six types of error perturbation on fifteen clustering algorithms

An evaluation of several clustering methods was conducted. Artificial clusters which exhibited the properties of internal cohesion and external isolation were constructed. The true cluster structure was subsequently hidden by six types of error-perturbation. The results indicated that the hierarchical methods were differentially sensitive to the type of error perturbation. In addition, generally poor recovery performance was obtained when random seed points were used to start theK-means algorithms. However, two alternative starting procedures for the nonhierarchical methods produced greatly enhanced cluster recovery and were found to be robust with respect to all of the types of error examined.     

Prejudice and peace: Is the Swedish youth neutral in its attitudes?

Two hundred and sixty Swedish students attending grade 9 were given a semantic differential to measure their attitudes towards four countries, Sweden, West Germany, USA, and the Soviet Union. The Soviet Union received significantly more unfavourable ratings on nearly all variables than the other countries, which received mainly favourable or neutral ones. Most interesting, the Soviet Union is rated as "enemy", whilst the other countries are rated as "friends". Implications for peace education are discussed.     

USE OF A SELF-RECORDING AND SUPERVISION PROGRAM TO CHANGE INSTITUTIONAL STAFF BEHAVIOR

The use of a self-recording and supervision program to increase interactions between direct care staff and profoundly retarded persons in a state residential facility was investigated. Following baseline, staff were provided with instructions regarding what to self-record, criteria for how many interactions to record, and a prepared card on which to make the recordings. Throughout the study, the staff supervisor monitored intermittently staff-client interactions. Observations indicated that when the staff recorded their interactions with clients in a loosely structured dayroom setting, the rate of interactions increased noticeably for each staff person. Behavioral ecology measures indicated that other staff responsibilities, such as maintaining the cleanliness of residents and the physical area, were not affected detrimentally when social interactions increased and actually showed small improvements. Additionally, small decreases in resident self-stimulatory and disruptive/aggressive behaviors occurred when the rate of social interactions from staff persons increased. Follow-up measures indicated that the rate of staff self-recording was variable, but when staff did self-record, the increased rate of staff-client interactions maintained.     

Standardized classroom management program: Social validation and replication studies in Utah and Oregon

A comprehensive validation study was conducted of the Program for Academic Survival Skills (PASS), a consultant-based, teacher-mediated program for student classroom behavior. The study addressed questions related to: (a) brief consultant training, (b) subsequent teacher training by consultants using PASS manuals, (c) contrasts between PASS experimental teachers and students and equivalent controls on measures of teacher management skills, student classroom behavior, teacher ratings of student problem behaviors, and academic achievement, (d) reported satisfaction of participants, and (e) replication of effects across two separate school sites. Results indicated that in both sites significant effects were noted in favor of the PASS experimental group for (a) teacher approval, (b) student appropriate classroom behavior, and (c) four categories of student inappropriate behavior. Program satisfaction ratings of students, teachers, and consultants were uniformly positive, and continued use of the program was reported a year later. Discussion focused upon issues of cost-effectiveness, differential site effects, and the relationship between appropriate classroom behavior and academic achievement.     

Time-series analysis in operant research

A time-series method is presented, nontechnically, for analysis of data generated in individual-subject operant studies, and is recommended as a supplement to visual analysis of behavior change in reversal or multiple-baseline experiments. The method can be used to identify three kinds of statistically significant behavior change: (a) changes in score levels from one experimental phase to another, (b) reliable upward or downward trends in scores, and (c) changes in trends between phases. The detection of, and reliance on, serial dependency (autocorrelation among temporally adjacent scores) in individual-subject behavioral scores is emphasized. Examples of published data from the operant literature are used to illustrate the time-series method.     

SHORT- AND LONG-TERM EFFECTS OF CONTINGENCY MANAGED INSTRUCTION ON LOW,MEDIUM, AND HIGH GPA STUDENTS1

Undergraduate students had been assigned to a contingency managed course or a conventional lecture course (Du Nann and Fernald, Journal of Applied Behavior Analysis, 1976, 9 , 373–374). Two years later, some 35% (N = 86) of the original classes responded to a letter offering them $2.00 to participate in a study of their educational experiences. These students completed a multiple-choice test on material from the course, and answered questions about activities and attitudes that might have been affected by the experience in Introductory Psychology. In the contingency management course 2 yr past, students were tested each week on a chapter of textbook material with 10-item multiple-choice quizzes. The course employed a modified “Doomsday Contingency”, requiring each student to achieve 80% mastery on one of the four weekly quizzes or drop the course. Quizzes were given in small groups and scored individually, while the student stood near, by an undergraduate proctor assigned to that group. The proctor was asked to show interest in the students' quiz performances, help clear up difficult areas, and develop a friendly working relationship with each student. While many students passed the quiz on the first attempt, others were given individual tutoring, so that no one was in fact forced to drop the course. In addition to the weekly quiz assignment, students in the contingency managed group were asked to attend one lecture each week. While the contingency management course procedures had much in common with PSI (Keller, Journal of Applied Behavior Analysis, 1968, 1 , 79–89), several departures made them unique. First, self-pacing was curtailed because students were required to master one unit per week or drop the course. Second, proctors met with students in small groups, usually giving individual tutoring only to those students who did not pass the quiz on the first attempt. Finally, students were asked to attend one lecture per week. Students in the conventional lecture group were not asked to pass weekly quizzes, but instead attended three 50-min lectures each week. Two of these lectures followed the textbook material closely, while the third, which was also attended by students from the contingency management course, covered material only indirectly related to the text. This partition of lecture content allowed material to be similar across the two instructional groups. Although students in the lecture condition were told they could obtain copies of the quizzes, few of them did so. Course grades were determined by scores on two 45-item multiple-choice hourly exams, each covering half the semester material (each worth 25%), and by a 90-item final exam, which served as a measure of short-term retention. Before analyzing the follow-up data, several characteristics of the returning students were compared to determine the comparability of the sample from the two original classes. Most important, both attrition and the current mean GPAs of students from the two classes were very similar. These considerations, and others, suggested there was no systematic sampling bias to confound comparisons of student performance. A 2 (contingency management versus traditional lecture) by 3 (high, medium, and low GPA) analysis of variance was computed on the course final-exam scores and the follow-up measures. Instructional procedure and GPA interacted on the final exam such that low and medium GPA students performed significantly better under contingency management, but there was no significant effect of instructional procedure with high GPA students. On the 2-yr retention measures, students from the contingency management course performed significantly (p < 0.01) better on items drawn from quizzes used in their original course, and marginally better (p < 0.10) on items drawn from the final exams, but no interactions with GPA appeared. Furthermore, instructional method produced no significant main effects or interaction with how many students became majors or minors in psychology, how many psychology courses were later taken, how many books in psychology were reported to have been read, or on students' evaluation of the interest and importance of psychology.     

MODIFICATION OF THE EXCESSIVE INAPPROPRIATE CLASSROOM BEHAVIOR OF TWO ELEMENTARY SCHOOL STUDENTS USING HOME-BASED CONSEQUENCES AND DAILY REPORT-CARD PROCEDURES1

Two experiments investigated home-based reinforcement contingencies to control excessive behavior in normal classrooms. Subjects were, respectively, a 12-yr-old fifth-grade boy and a 9-yr-old fourth-grade boy, each in a separate classroom and with a different teacher. Following baseline observations in which observers recorded several categories of student behavior and teacher-student interaction, separate conferences were held including parents of the two children, the principal, teachers, and experimenters. A daily report-card procedure was agreed on, stipulating a one-day suspension from school following three successive “undesirable” daily report cards as well as the supervision of home-based privileges and other reinforcers usually contingent on satisfactory daily reports. Measurements of daily rates of teacher attention indicated no important change in this variable throughout the various experimental conditions. The daily report procedure significantly reduced disruptive classroom behavior. In a second experiment, a teacher-operated timer cued her own time-sample observations. Reliability measures revealed that the teacher could accurately measure the child's behavior while she was teaching the class. The procedure was ultimately successfully expanded to the teacher's total contact hours each day.     

管理者影响策略的结构

本研究根据中国企事业组织内管理者对他人发挥影响力的特点 ,选取反映中国文化的影响计策编成题目 ,并与西方背景下构建的组织影响策略量表汇编成问卷。 2 1 8位中国管理者用汇编的问卷评定他们与直接上司和直接下属在工作中相处时使用这些计策的频率。结果发现 ,在因素水平有“应变控制”和“温情说服”两个正交因素。这两个因素跨影响方向一致。对各因素内的题目做聚类分析 ,发现大多数聚类的内容跨影响方向的一致性不高。与西方的组织策略量表对照 ,因新题目的加入 ,汇编的影响计策量表内的聚类更好地反映了中国管理者使用影响计策的特点。     

个人化设计在临床研究中的应用——从个体角度研究个体差异

本文从有关研究证据的基础上,介绍了个人化设计的理论基础和实验设计,并在此基础上讨论了个人化设计在临床研究领域中的应用价值,总结出一种适合临床病人使用的研究程序。个人化设计允许对个体的个人价值进行分析,并能同时研究不同刺激信息的作用,在个体水平上分析个体差异。通过简化了的实验程序,个人化设计为解决临床研究中的问题提供了一种新的思维方式。文中还对相关研究法的局限进行了讨论。     

团队决策及其影响因素

随着组织结构的变化,团队决策为越来越多的组织所采用。该文将团队决策的研究范式概括为以下四类：社会决策图式（social decision scheme, SDS）、信息取样模型（information sampling model）、项目排序任务（ranking item task）团队以及组织中以安全优先的团队（safety priority team）;并从影响团队决策的因素,提高团队决策质量的策略等角度分别对四类团队决策的研究进行探讨,在此基础上本文对未来研究进行了展望