Intelligent information retrieval: diagnosing information need. : Part I. The theoretical framework for developing an intelligent IR tool

The research examines the notion that the principles underlying the procedure used by doctors to diagnose a patient's disease are useful in the design of “intelligent” IR systems because the task of the doctor is conceptually similar to the computer (or human) intermediary's task in “intelligent information retrieval”: to draw out, through interaction with the IR system, the user's query/information need. The research is reported in two parts. In Part II, an information retrieval tool is described which is based on “intelligent information retrieval” assumptions about the information user. In Part I, presented here, the theoretical framework for the tool is set out. This framework is borrowed from the diagnostic procedure currently used in medicine, called “differential diagnosis”. Because of the severe consequences that attend misdiagnosis, the operating principle in differential diagnosis is (1) to expand the uncertainty in the diagnosis situation so that all possible hypotheses and evidence are considered, then (2) to contract the uncertainty in a step by step fashion (from an examination of the patient's symptoms, through the patient's history and a physical (signs), to laboratory tests). The IR theories of Taylor, Kuhlthau and Belkin are used to demonstrate that these medical diagnosis procedures are already present in IR and that it is a viable model with which to design “intelligent” IR tools and systems.     

The effects of being a reader and of observing readers on fifth-grade students’ argumentative writing and revising

Opportunities to read and analyze others?? writing or to observe readers as they analyze writing might enhance one??s own sense of audience and improve one??s own writing. This mixed-methods study investigated whether reader and observer activities in comparison to writing practice activities affected fifth-grade students?? persuasive writing and revising. After writing a first draft of a persuasive letter, 87 fifth-grade students were randomly assigned to one of three conditions: being a reader, observing readers, or practicing writing. The reader group read and discussed three persuasive letters, considering whether they were persuasive and why and selecting the most persuasive. The observer group listened to the reader group??s discussions and took notes; then they had their own discussion to generate a list of criteria for what made the letters persuasive. The practice-writing control group practiced writing persuasive letters. Afterwards, all groups revised their first drafts. The reader group produced second drafts that were of better quality and contained more evidence of audience awareness than the control group. The observer group did not differ from either group. The groups did not differ on a transfer task occurring 1-week later. The authors discuss implications for designing writing curriculums that utilize reader and observer activities.     

Connections between Student Explanations and Arguments from Evidence about Plant Growth

We investigate how students connect explanations and arguments from evidence about plant growth and metabolism—two key practices described by the Next Generation Science Standards. This study reports analyses of interviews with 22 middle and high school students postinstruction, focusing on how their sense-making strategies led them to interpret—or misinterpret—scientific explanations and arguments from evidence. The principles of conservation of matter and energy can provide a framework for making sense of phenomena, but our results show that some students reasoned about plant growth as an action enabled by water, air, sunlight, and soil rather than a process of matter and energy transformation. These students reinterpreted the hypotheses and results of standard investigations of plant growth, such as van Helmont''s experiment, to match their own understanding of how plants grow. Only the more advanced students consistently interpreted mass changes in plants or soil as evidence of movement of matter. We also observed that a higher degree of scaffolding during some of the interview questions allowed mid-level students to improve their responses. We describe our progress and challenges developing teaching materials with scaffolding to improve students’ understanding of plant growth and metabolism.     

Development of social category representations: early appreciation of roles and deontic relations

Three experiments explored the significance of deontic properties (involving rights and obligations) in representations of social categories. Preschool-aged children ( M = 4.8), young school-aged children ( M = 8.2), and adults judged the centrality of behavioral, psychological, and deontic properties for both familiar (Experiments 1 and 2, N s = 50 and 52, respectively) and novel (Experiment 3, N = 64) social categories. Preschool-aged children were the most consistent in treating deontic properties as central: Knowing a person's social category membership was more informative about obligations than about behavioral frequencies or psychological preferences. Adults treated deontic properties as central to some categories but also recognized a set that was primarily predictive of psychological dispositions. The results argue for the significance of deontic properties in the development of social cognition.     

Random and blocked practice of movement sequences: differential effects on response structure and movement speed

Three similar six-element key press sequences were practiced under blocked or random practice schedules with acquisition conducted on one day and retention and transfer on the next day. The task required participants to type, as quickly as possible, one of three 6-element sequences as observed on a computer monitor. In blocked practice, participants completed all practice in one repeated sequence before the next repeated sequence was introduced. In random acquisition practice, the three repeated sequences were randomly presented to the participants. The data suggest that random practice results in participants adopting a uniform response structure, while blocked practice allows participants to exploit unique sequential aspects of the individual tasks. This finding suggests that random practice may not be as effective as blocked practice when one of the tasks being practiced together can be optimized through the development of a unique response structure.     

Accuracy and Prediction in Throwing: A Taxonomic Analysis of Children's Performance

Abstract

The throwing and prediction performances of first, third and fifth grade boys and girls were analyzed within the framework of a four-part taxonomy originally conceived by Fitts (1965). Throwing performance was assessed under task conditions which varied the motion states of the thrower's body and the target (stationary or moving) by use of a dual pendulum apparatus. Accuracy scores were highest in a condition where both body and target were stationary, and lowest where both body and target were moving. Task conditions requiring motion of only target or of body were of intermediate difficulty, and scores for these tasks were not significantly different from each other. There was evidence of learning across trial blocks for all tasks, but no indication that rates of acquisition differed for the task types. Likewise, significant main effects were observed for age levels but no age X task type interactions were disclosed. Boys were more accurate than girls across task conditions, most noticeably on the two most difficult tasks. Comparison of subjects' ability to predict, from a stationary body position, the coincidence of the moving target with a standard reference point, and their ability to predict the coincidence of their moving body with the same reference point revealed lower error scores on the former prediction task.     

The effects of instruction on college nonmajors' conceptions of respiration and photosynthesis

Students in a college nonscience majors' biology course took tests designed to reveal their conceptions of respiration and photosynthesis before and after course instruction. Even though most students had taken at least a full year of biology, serious misconceptions persisted. Most students gave definitions of respiration, photosynthesis, and food which were markedly different from those generally accepted by biologists. These incorrect definitions were associated with more fundamental misunderstandings about how plants and animals function. Most students could not explain how animal cells use either food or oxygen. They understood plants as vaguely analogous to animals, taking in food through their roots instead of mouths. Previous biology instruction seemed neither to improve student performance on the pretest nor to prepare them to master these conceptions during the course. Course instruction did improve student's understanding, but misconceptions persisted for many students. These results raise fundamental questions about the effectiveness of curriculum and instruction in current high school and college biology courses.     

Preferences among Alternative Test Outcomes

To develop a procedure for determining the dominance of various social motives operative in classroom settings and to provide a didactic method for illustrating social motives, college students were requested to rank their preferences among alternative distributions of own and others’ scores on a test covering the content of a course. It was found that outcomes that maximized own scores were preferred by a majority of students, but only in that instance where their highest score was slightly better than that obtained by their classmates. Less than a majority of students preferred the same score which maximized their own absolute outcome when it was slightly lower than their classmates’ scores. Evidence was found in the preference data for the presence of the social motivational orientations of individualism (own gain maximization), competition (relative gain maximization), cooperation (joint gain maximization), and equity (equality maximization). The verbal rationales provided by students for their preferences were strongly consistent with the motivational properties of preferred own and other outcomes.