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Les brasseurs aiment connaǐtre la relation entre les caractéristiques chimiques de leurs bières et les préférences exprimées par les consommateurs. Deux ensembles de données furent fournis aux analystes. Le premier comprenait une série de caractéristiques chimiques mesurées sur 91 bières ainsi que des mesures de préférence, pour les měmes bières, recueillies lors de tests où les types de bières ne sont pas connus des dégustateurs. On demanda aux analystes d'utiliser ces données afin d'élaborer un modèle statistique permettant de relier les caractéristiques chimiques d'une bière aux préférences des consommateurs. Le deuxième ensemble de données était constitué de mesures sur 37 bières non incluses dans le premier ensemble. Les analystes devaient utiliser le modèle proposé afin de prédire la cote de préférence des consommateurs pour ces bières. On compare les performances des différents modèles proposés. [ABSTRACT FROM AUTHOR]

Comments on an article by Duane G. Harris and Richard F. Nehring on a theoretical model of the maximum bid price for agricultural land and the application of the model to cash-grain farms in Iowa. Formulation of a revised model; Implications of the model; Application of the model to data provided by Harris and Nehring.

Objective: There has been an increase in the use of neoadjuvant chemotherapy in recent years. Our objective was to determine if African American women are more likely to receive neoadjuvant chemotherapy than primary debulking surgery, when compared to their Caucasian counterparts, and the impact of such an approach on oncologic outcomes., Methods: A retrospective cohort study was performed using the National Cancer Database (NCDB). Women aged 18-90 years, diagnosed with stage IIIC or IV epithelial ovarian cancer between January 2010 through December 2014 were included. Women with unknown treatment or treatments outside of neoadjuvant chemotherapy or primary debulking surgery were excluded. Only women of Caucasian, African American, or Hispanic origin who received either neoadjuvant chemotherapy or primary debulking surgery were included; all other races were excluded. Descriptive statistics were computed, and continuous variables were assessed for normality. Groups were compared using ANOVA or non-parametric medians tests for continuous variables, and chi-squared tests were used for dichotomous or categorical variables. Logistic regression was used to identify predictors of treatment. A p value of 0.05 was considered statistically significant., Results: A total of 19 838 women with stage IIIC and IV epithelial ovarian cancer met the inclusion criteria. A total of 14 988 (75.6%) were treated with primary debulking surgery, while 4850 women (24.4%) were treated with neoadjuvant chemotherapy. Of those treated with neoadjuvant chemotherapy, 24.5% were white, 27.0% were African American, and 22.1% were Hispanic (p=0.005), and when adjusted for confounders, being African American was a predictor of receiving neoadjuvant chemotherapy (adjusted odds ratio (aOR) 1.29, 95% CI 1.10 to 1.51). Ninety-day mortality rates were higher in African American women compared with Caucasian and Hispanic women (2.9% vs 2.0% vs 1.6%, p=0.013). There were no differences in 30-day mortality, 90-day mortality, or status at last contact in African American women, when comparing neoadjuvant chemotherapy and primary debulking surgery. In Caucasian women, outcomes were worse in women receiving neoadjuvant chemotherapy., Conclusions: Compared to other races, African American women with advanced ovarian cancer are more likely to receive neoadjuvant chemotherapy than primary debulking surgery and had a higher 90-day mortality rate. In African American women there was no difference in outcomes based on treatment type., Competing Interests: Competing interests: None declared., (© IGCS and ESGO 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Babies born live under 2,500 g or with a gestational age under 37 weeks are often inadequately developed and have elevated risks of infant mortality, congenital malformations, mental retardation, and other physical and neurological impairments. In this paper, we model birth weight as a first hitting time (FHT) of a birthing boundary in a Wiener process representing fetal development. We associate the parameters of the process and boundary with covariates describing maternal characteristics and the birthing environment using a relatively new regression methodology called threshold regression. Two FHT models for birth weight are developed. One is a mixture model and the other a competing risks model. These models are tested in a case demonstration using a 4%-systematic sample of the more than four million live births in the United States in 2002. An extensive data set for these births was provided by the National Center for Health Statistics. The focus of this paper is on the conceptual framework, models and methodology. A full empirical study is deferred to a later occasion.