We propose a new generator of continuous distributions with one extra positive parameter called the odd Lindley-G family. Some special cases are presented. The new density function can be expressed as a linear combination of exponentiated densities based on the same baseline distribution. Various structural properties of the new family, which hold for any baseline model, are derived including explicit expressions for the quantile function, ordinary and incomplete moments, generating function, Rényi entropy, reliability, order statistics and their moments and k upper record values. We provide a Monte Carlo simulation study to evaluate the maximum likelihood estimates. We discuss estimation of the model parameters by maximum likelihood and provide an application to a real data set.

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We study general mathematical properties of a new generator of continuous distributions with three extra shape parameters called the beta Marshall-Olkin family. We present some special models and investigate the asymptotes and shapes. The new density function can be expressed as a mixture of exponentiated densities based on the same baseline distribution. We derive a power series for its quantile function. Explicit expressions for the ordinary and incomplete moments, quantile and generating functions, Bonferroni and Lorenz curves, Shannon and Rényi entropies and order statistics, which hold for any baseline model, are determined. We discuss the estimation of the model parameters by maximum likelihood and illustrate the flexibility of the family by means of two applications to real data.

We investigated the prevalence of body image dissatisfaction (BID) and associated factors among professors and undergraduate students in Brazil during the COVID-19 pandemic. Using Stunkard’s Figure Rating Scale, BID was analyzed in a sample of 2,220 adults. The independent variables were sociodemographic, lifestyle, mental health symptoms, COVID-19-related factors, disordered eating, experience of weight stigma, and weight change concerns. We used a multinomial logistic regression analysis. The overall prevalence of BID was 82.5% (69.0% due to excess weight), with more professors dissatisfied by excess weight than undergraduate students (78.9% vs. 61.2%, p < 0.001). In the adjusted model, being a young adult (PR, 1.201, 95% CI: 1.128; 1.279), married or in a stable union (PR, 1.088, 95% CI: 1.027; 1.152), reporting of binge eating episode (PR, 1.120, 95% CI: 1.068; 1.173), concern about weight gain (PR, 1.394, 95% CI: 1.310; 1,483), and experience of excess weight stigma (PR, 1.193, 95% CI: 1.141; 1.248) increased the prevalence of BID due to excess weight. While males (PR, 1.578, 95% CI: 1.328; 1.875), moderate to severe depressive symptoms (PR, 1.217, 95% CI: 1.011; 1.465), the concern of losing weight (PR, 1.494, 95% CI: 1.221; 1.830), and experience of low weight stigma (PR, 2.620, 95% CI: 2.093; 3.280) increased the prevalence of BID due to low weight. Different factors associated with BID were observed between students and professors. Bearing in mind the complexity of body image, it is essential to consider different public health interventions and the COVID-19 pandemic’s influence on reducing BID among Brazilian adults, especially susceptible groups.

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