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21.
Determining heterogeneous behavior for theater attendance   总被引:2,自引:1,他引:1  
In this paper we propose and estimate a model of theater participation using the data contained in the 2002 Survey of Public Participation in the Arts from the USA, a dataset widely used to study the determinants of cultural participation. Our contribution relies on the use of an estimation technique that respects the count data nature of the attendance variable (number of theater performances that an individual attended) and allows for heterogeneous behavior. By using a Zero Inflated Negative Binomial Model, we can characterize two distinct behaviors for the observable attendance: a group of never-goers (who never participate) and a subpopulation that has a positive probability of attending. For this latter group, we can estimate the effect of certain personal variables on the probability of highest frequency. The results suggest that the proposed model is appropriate for estimating cultural participation.
Victoria Ateca-AmestoyEmail:
  相似文献   
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The purpose of this study was to compare submaximal physiological responses and indices of mechanical efficiency between asynchronous and synchronous arm ergometry. Thirteen wheelchair-dependent trained athletes performed eight steady-state incremental bouts of exercise (0 to 140 W), each lasting 4 min, using synchronous and asynchronous arm-cranking strategies. Physiological measures included oxygen uptake (VO2), heart rate, and blood lactate concentration. The power outputs corresponding to fixed whole blood lactate concentrations of 2.0 to 4.0 mmol x l(-1) were calculated using linear interpolation. Mechanical efficiency indices - gross efficiency, net efficiency, and work efficiency - were also calculated. An analysis of variance with repeated measures was applied to determine the effect of crank mode on the physiological parameters. Oxygen uptake was on average 10% lower (P < 0.01), and both net efficiency (P < 0.01) and gross efficiency (P < 0.01) were higher, during the asynchronous strategy at both 60 and 80 W (gross efficiency: 16.9 +/- 2.0% vs. 14.7 +/- 2.4% and 17.5 +/- 1.8% vs. 15.9 +/- 2.6% at 60 and 80 W respectively). There were no differences in heart rate, blood lactate concentration or power output at either of the blood lactate reference points between the asynchronous and synchronous strategies (P > 0.05). In conclusion, test specificity is an important consideration. If a synchronous strategy is to be adopted, it is likely to result in lower efficiency than an asynchronous strategy. The exercise testing scenario may help dictate which method is ultimately chosen.  相似文献   
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In cricket bowling, the reconstruction of elbow angle data is of utmost importance to the bowling versus throwing argument. This paper reviews system and modelling errors inherent in three-dimensional reconstruction processes with respect to the elbow extension tolerance set by the International Cricket Council. An understanding of these factors will enable more informed decisions about the choice of in-field versus laboratory testing in the calculation of elbow extension during bowling in cricket. Although there is a paucity of objective data related to in-field and laboratory testing, biomechanists must be guided by the greater accuracy of opto-reflective than video-based systems and so testing, at least for the present, should be conducted in a laboratory setting.  相似文献   
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CLOCKSS (Controlled Lots of Copies Keep Stuff Safe) is a community-wide endeavor built upon the widely used LOCKSS system. CLOCKSS is working to guarantee long-term access to digital materials regardless of ability to pay. Two lively sessions led by Victoria Reich, Director of the LOCKSS Program at Stanford University Libraries, were packed to capacity. Librarian and publisher participants in CLOCKSS are implementing a shared solution to one of the most significant challenges of the digital era.  相似文献   
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The aim of this study was to examine the relationship between shoulder alignment and elbow angle during the delivery action of fast-medium bowlers. The elbow and upper trunk alignment were recorded for 13 high-performance bowlers (mean age 20 years) using a 12-camera Vicon motion analysis system operating at 250 Hz. The three highest velocity trials for "good" and "short" length deliveries were analysed. Results showed that bowlers with a more front-on shoulder alignment at back-foot impact and when the upper arm was horizontal to the ground experienced a significantly greater elbow flexion--extension range when compared with those who had a more side-on orientation at the same point in the delivery action. Bowlers with greater shoulder counter-rotation also recorded higher elbow flexion and subsequently extension during the period from upper arm horizontal to ball release. Shoulder alignment and elbow angles were similar for "short" and "good" length deliveries. It was concluded that bowlers with a more front-on shoulder orientation at back-foot impact demonstrated a higher elbow extension from upper arm horizontal to ball release and are therefore more likely to infringe International Cricket Council elbow tolerance levels, compared with those who adopt a more side-on shoulder orientation at back-foot impact.  相似文献   
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This essay situates the television show Breaking Bad (BB) and its critical reception in the context of American politics following the economic and political events of 2008. Reading the show as an allegory, I demonstrate that it offered a pathway for viewers to maintain investments and commitments to a toxic, white masculinity threatened by 2008’s economic and political dislocations. Taking the show up for its capacity to allegorize the human experience, Breaking Bad’s critically acclaimed status among viewers from widely divergent political positions suggests that the investment in raced and gendered ideas of individual freedom crosses partisan lines, indicating that American national identity and white masculinity share a mutually sustaining incoherence. Understanding the cultural roots of American victimage evident in post-2008 America helps explain how BB distinguished itself from similar masculine “anti-hero” dramas.  相似文献   
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OBJECTIVES: Medicine must keep current with the research literature, and keeping current requires continuously updating the clinical knowledge base (i.e., references that provide answers to clinical questions). The authors estimated the volume of medical literature potentially relevant to primary care published in a month and the time required for physicians trained in medical epidemiology to evaluate it for updating a clinical knowledge base. METHODS: We included journals listed in five primary care journal review services (ACP Journal Club, DynaMed, Evidence-Based Practice, Journal Watch, and QuickScan Reviews). Finding little overlap, we added the 2001 "Brandon/Hill Selected List of Print Books and Journals for the Small Medical Library." We counted articles (including letters, editorials, and other commentaries) published in March 2002, using bibliographic software where possible and hand counting when necessary. For journals not published in March 2002, we reviewed the nearest issue. Five primary care physicians independently evaluated fifty randomly selected articles and timed the process. RESULTS: The combined list contained 341 currently active journals with 8,265 articles. Adjusting for publication frequency, we estimate 7,287 articles are published monthly in this set of journals. Physicians trained in epidemiology would take an estimated 627.5 hours per month to evaluate these articles. CONCLUSIONS: To provide practicing clinicians with the best current evidence, more comprehensive and systematic literature surveillance efforts are needed.  相似文献   
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