ANCOVA (analysis of covariance) is a widely used statistical method for comparing the mean values of multiple groups on a continuous outcome while adjusting for the influence of a related continuous variable. ANCOVA extends ANOVA (analysis of variance) by integrating a continuous independent variable into the model to minimize bias and control for potential confounding […]
In this Statistics Note, we learn how to create Q-Q plots from the scratch in R. A quantile-quantile plot (Q-Q plot for short) is a scatter plot that shows how one empirical distribution approximates a theoretical distribution. Before we dive into QQ plots, let’s clarify an important concept: quantiles. What is a quantile? A quantile
Confounders are undesirable variables that affect the relationship between two variables of interest in a study. For example, in epidemiological research studying the effects of a nutrient on a health issue, such as diabetes, the participant’s body size or physical activity can confound the relationship between the nutrient and the health issue. Therefore, it is