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Advances in commercially-available ASR technology have enabled the deployment of “How-may-I-help-you?” interactions to automate call routing. While often preferred to menu-based or directed dialog strategies, there is little quantitative research into the relationships among prompt style, task completion, user preference/satisfaction, and domain. This work applies several dialog strategies to two domains, drawing on both real callers and usability subjects. We find that longer greetings produce higher levels of first-utterance routability. Further, we show that a menu-based dialog strategy produces a uniformly high level of routability at the first utterance in two domains, whereas an open-dialog approach varies significantly with domain. In a domain where users lack an expectation of task structure, users are most successful with a directed strategy, for which preference scores are highest, even though it does not result in the shortest dialogs. Callers rarely provide more than one piece of information in their responses to all types of dialog strategies. Finally, a structured dialog repair prompt is most helpful to callers who were greeted with an open prompt, and least helpful to callers who were greeted with a structured prompt. 相似文献
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H Bahramali E Gordon WM Li C Rennie J Wright R Meares 《Canadian Metallurgical Quarterly》1998,95(3-4):155-165
A number of studies have examined across-trial averaged late component. Event Related Potentials (EPR) and Reaction Times (RT) in response to multiple target stimuli. In this study, within-trial relatively fast and slow sub averages are additionally examined, in 20 patients with schizophrenia and 20 age and sex matched controls. A conventional auditory oddball paradigm. Across-trial ERP average analysis showed smaller N200 amplitude and delayed latency (but larger P200 amplitude) in patients with schizophrenia compared with controls. Within-trial ERP analysis revealed a number of additional findings. Controls showed distinctive differences in fast compared with slow ERP sub averages (smaller P200 amplitude, increased N200/P300 amplitudes and earlier latencies). The schizophrenic group on the other hand, showed relatively similar fast versus slow subaverages (no differences in P200 amplitude and N200 latency). In addition, between-group (within-trial) analyses highlighted significant differences in earlier stages of processing (compared with across-trial averages) in both fast and slow subaverages (increased N100 amplitude in controls). The complementary within-trial (compared with across-trial) data are interpreted with respect to a possible disturbance in inhibitory function in patients with schizophrenia. 相似文献
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Whereas patients with multiple myeloma continue to relapse after autologous transplantation and are unlikely to be cured, the probability of progression is less after allogeneic transplantation and a proportion of patients may be cured. This is attributable to an immunologically mediated graft-versus-myeloma (GVM) effect which is akin to the well-known graft-versus-leukemia effect. The available clinical and experimental evidence strongly support the existence of GVM, but it is not known whether GVM is separable from graft-versus-host disease (GVHD) in practice. The best way to exploit GVM reactions is unclear, and the morbidity and mortality associated with GVHD undermine long-term survival. There is usually a time lag of a few weeks between immune intervention and disease response. There is a propensity for extramedullary disease recurrence in patients whose marrow disease is controlled with immunologic manipulation. Exploration of GVM outside conventional allogeneic transplantation or after autologous transplantation is necessary to increase the number of patients likely to benefit from this phenomenon and to make it safer. This article reviews the currently available literature on the subject. 相似文献
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GW Petty RD Brown JP Whisnant JD Sicks WM O'Fallon DO Wiebers 《Canadian Metallurgical Quarterly》1998,50(6):1669-1678
A variety of methods was used to compare patient mix, practice variation, survival, and recurrence after first ischemic stroke among Rochester, MN residents. The significance of the results for neurologists and generalists was examined. Age, stroke severity, congestive heart failure (CHF), and the interaction between atrial fibrillation and patient groups were determinants of survival. Without atrial fibrillation, patients on neurology services and patients on general services with neurology consultation had better survival than those without neurology consultation, adjusting for age, stroke severity, and CHF. With atrial fibrillation, patients on general services with neurology consultation had no better survival compared with those without neurology consultation; patients on neurology services had worse survival (p=0.002). There was no difference in stroke recurrence. Evaluation by a neurologist is associated with better survival for most patients with ischemic stroke but not those with atrial fibrillation. Only a randomized trial can determine whether this association is causal. 相似文献
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Maternal immunization might protect infants from severe disease due to respiratory syncytial virus (RSV). Guinea pigs are susceptible to infections with RSV and transfer antibodies to their offspring prenatally. Pregnant guinea pigs were immunized by infection with RSV and their offspring were challenged intranasally with RSV. Pulmonary viral replication was compared among the pups born to immunized mothers (group A) and the pups from nonimmune mothers (group B) in two studies. Mean (+/-SD) log10 virus titers were, in study 1, group A, 2.3 +/- 0.8 pfu/g of lung (n = 10); group B, 3.6 +/- 1.5 pfu/g (n = 13) (P = .0058); and study 2, group A, < 1.69 pfu/g (n = 8); group B, 3.4 +/- 0.9 pfu/g (n = 6) (P = .0002). Thus, immunization of pregnant guinea pigs resulted in a significant reduction in viral replication in the lungs of their offspring. Guinea pigs should be useful for the study of maternal immunization against RSV. 相似文献