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41.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty. 相似文献
42.
The aim of this study was to examine the effectiveness of either a standard care programme (n = 9) or a 12-week supported exercise programme (n = 10) on glycaemic control, β-cell responsiveness, insulin resistance, and lipid profiles in newly diagnosed Type 2 diabetes patients. The standard care programme consisted of advice to exercise at moderate to high intensity for 30 min five times a week; the supported exercise programme consisted of three 60-min supported plus two unsupported exercise sessions per week. Between-group analyses demonstrated a difference for changes in low-density lipoprotein cholesterol only (standard care programme 0.01 mmol · L(-1), supported exercise programme -0.6 mmol · L(-1); P = 0.04). Following the standard care programme, within-group analyses demonstrated a significant reduction in waist circumference, whereas following the supported exercise programme there were reductions in glycosylated haemoglobin (6.4 vs. 6.0%; P = 0.007), waist circumference (101.4 vs. 97.2 cm; P = 0.021), body mass (91.7 vs. 87.9 kg; P = 0.007), body mass index (30.0 vs. 28.7 kg · m(-2); P = 0.006), total cholesterol (5.3 vs. 4.6 mmol · L(-1); P = 0.046), low-density lipoprotein cholesterol (3.2 vs. 2.6 mmol · L(-1); P = 0.028), fasting β-cell responsiveness (11.5 × 10(-9) vs. 7.0 × 10(-9) pmol · kg(-1) · min(-1); P = 0.009), and insulin resistance (3.0 vs. 2.1; P = 0.049). The supported exercise programme improved glycaemic control through enhanced β-cell function associated with decreased insulin resistance and improved lipid profile. This research highlights the need for research into unsupported and supported exercise programmes to establish more comprehensive lifestyle advice for Type 2 diabetes patients. 相似文献
43.
Anna H. Hall Michael D. Toland Jennifer Grisham-Brown Steve Graham 《Early Childhood Education Journal》2014,42(6):423-430
The current study used a pretest–posttest randomized control group design with 73 Head Start students, ages 3–5 years. The researcher served as the interactive writing teacher for the treatment group, rotating to five different classrooms in one Head Start center 3–4 days a week for 13 weeks. Children in the treatment group received a 10–15 min interactive writing lesson each day in small groups within their own classroom settings. Children in the control group received standard literacy instruction in small groups with their own classroom teachers. Child outcome data on upper case, lower case, and letter sound identification were collected before and after the intervention for both groups. Based on the large frequency of zeros on outcomes, zero-inflated Poisson regression analyses were performed. The results of the study showed that children receiving interactive writing identified more lower case and upper case letters at the end of the study relative to children in the control, but no differences were observed on letter sounds. While continued evaluation of the interactive writing strategy is needed in the preschool setting, the evidence from the current study shows encouraging trends in alphabet knowledge skill development as a result of this strategy. 相似文献
44.
Steve Masson Patrice Potvin Martin Riopel Lorie‐Marlène Brault Foisy 《Mind, Brain, and Education》2014,8(1):44-55
Science education studies have revealed that students often have misconceptions about how nature works, but what happens to misconceptions after a conceptual change remains poorly understood. Are misconceptions rejected and replaced by scientific conceptions, or are they still present in students' minds, coexisting with newly acquired scientific conceptions? In this study, we use functional magnetic resonance imaging (fMRI) to compare brain activation between novices and experts in science when they evaluate the correctness of simple electric circuits. Results show that experts, more than novices, activate brain areas involved in inhibition when they evaluate electric circuits in which a bulb lights up, even though there is only one wire connecting it to the battery. These findings suggest that experts may still have a misconception encoded in the neural networks of their brains that must be inhibited in order to answer scientifically. 相似文献
45.
46.
This paper describes the structure and use of LabAssistant, a software shell purposely written to run alongside engineering laboratory exercises and provide support to students undertaking the exercises. The structure of LabAssistant enables tutors to deliver their own laboratory sessions within the shell using only basic spreadsheet skills. LabAssistant is intended to be used in conjunction with in-depth, analytical laboratory exercises and its features include text entry, numerical input and checking (including verification of calculated values and provision of appropriate feedback), graph sketching, data plotting and report generation. Feedback from students confirms that LabAssistant has enhanced the learning experience, encouraging active engagement, building confidence and assisting progression through the exercise, even using the data and information input during the session to generate the majority of their laboratory write-up automatically. From the tutor's perspective, the provision of immediate and continual help to the students is a significant enhancement to the quality of the learning experience. LabAssistant complements the tutor who is now able to deal effectively with deeper conceptual difficulties and larger student numbers. The facility to verify all calculated values and the creation of a report in a standard electronic format are significant aids to the marking of student submissions. 相似文献
47.
48.
Leslie C. Higgins 《Educational technology research and development : ETR & D》1978,26(3):215-232
Many questions about picture interpretation behavior remain to be answered One question relates to the psychological nature of such behavior and may be stated; What psychological processes are involved in drawing inferences from pictures? This study attempts to answer the question using a model of picture interpretation that consists of two interdependent forms of behavior: observation and inference drawing. The study focuses on the latter, which is further divided into productive and evaluative processes. These are accounted for by three constructs: operational facility, the ability to generalize concepts, and conceptual fluency. To test the model and related hypotheses, two pictorial tests of inference drawing and 19 reference tests were administered to 95 children aged 10 to 12 years, A factor analytic methodology was employed. 相似文献
49.
50.
In an attempt to ensure students had a positive experience in their first semester, and to encourage future effective use of tutors’ feedback comments, a post-1992 university used a module in the school of education to develop an innovative feedback process. The process involved four stages: a first submission of written work, written feedback on that work, viva on student understanding of feedback, and final submission of written work. Between the viva and final submission, students could choose to improve their work for a specified number of grade points. The innovation was met favourably by students, and overall grades were improved against the previous iteration of the module. The project showed promise for adaptation in other forms for use across the University, though some ideological issues around assessment remain unresolved. The matter of the innovation and institutional quality standards is discussed in detail. 相似文献