Importância das características na precificação de veículos nacionais Importance of characteristics in pricing national vehicles

O mercado de bens de consumo é constituído por produtos heterogêneos que podem ser vistos como uma união de atributos ou características. Quantificar o valor dessas características pode auxiliar na criação de uma regra de precificação que permita, por exemplo, precificar um produto não existente, auxiliando na sua previsão de demanda. O objetivo deste trabalho é utilizar a teoria do preço hedônico para determinar empiricamente o valor e a importância relativa das características na precificação de veículos nacionais brasileiros. O modelo de previsão foi obtido utilizando-se uma função hedônica linear, cujos coeficientes foram estimados através de mínimos quadrados ordinários. Pode-se concluir que a potência é o fator de maior impacto no preço de um veículo, seguido pelo grau de luxo e marca.<br>The market of consumer goods is consisted of heterogeneous products which can be viewed as a union of attributes or characteristics. Quantifying the value of these characteristics can help in the creation of a pricing rule, allowing, for example, pricing a product which is not available, and helping in the estimates of its demand. The purpose of this work is to use the theory of hedonic price to determine empirically the value of characteristics, as well as their relative importance, in the price of Brazilian vehicles. The model was obtained using data regarding 150 national vehicles and a linear hedonic function, which coefficients were estimated by ordinary least squares. It can be concluded that the engine power is the factor which has the greatest impact on a vehicle price, followed by the luxury level and the brand

Correction: Mortality and other outcomes of patients with coronavirus disease pneumonia admitted to the emergency department: A prospective observational Brazilian study.

[This corrects the article DOI: 10.1371/journal.pone.0244532.]

Mortality and other outcomes of patients with coronavirus disease pneumonia admitted to the emergency department: A prospective observational Brazilian study.

BackgroundThe first cases of coronavirus disease (COVID-19) in Brazil were diagnosed in February 2020. Our Emergency Department (ED) was designated as a COVID-19 exclusive service. We report our first 500 confirmed COVID-19 pneumonia patients.MethodsFrom 14 March to 16 May 2020, we enrolled all patients admitted to our ED that had a diagnosis of COVID-19 pneumonia. Infection was confirmed via nasopharyngeal swabs or tracheal aspirate PCR. The outcomes included hospital discharge, invasive mechanical ventilation, and in-hospital death, among others.ResultsFrom 2219 patients received in the ED, we included 506 with confirmed COVID-19 pneumonia. We found that 333 patients were discharged home (65.9%), 153 died (30.2%), and 20 (3.9%) remained in the hospital. A total of 300 patients (59.3%) required ICU admission, and 227 (44.9%) needed invasive ventilation. The multivariate analysis found age, number of comorbidities, extension of ground glass opacities on chest CT and troponin with a direct relationship with all-cause mortality, whereas dysgeusia, use of angiotensin converting enzyme inhibitor or angiotensin-ii receptor blocker and number of lymphocytes with an inverse relationship with all-cause mortality.ConclusionsThis was a sample of severe patients with COVID-19, with 59.2% admitted to the ICU and 41.5% requiring mechanical ventilator support. We were able to ascertain the outcome in majority (96%) of patients. While the overall mortality was 30.2%, mortality for intubated patients was 55.9%. Multivariate analysis agreed with data found in other studies although the use of angiotensin converting enzyme inhibitor or angiotensin-ii receptor blocker as a protective factor could be promising but would need further studies.Trial registrationThe study was registered in the Brazilian registry of clinical trials: RBR-5d4dj5