question: Describe f-scLVM
answer: Single-cell RNA-sequencing (scRNA-seq) allows studying heterogeneity in gene expression in large cell populations. Such heterogeneity can arise due to technical or biological factors, making decomposing sources of variation difficult. F-scLVM (factorial single-cell latent variable model) is a method based on factor analysis that uses pathway annotations to guide the inference of interpretable factors underpinning the heterogeneity. The model jointly estimates the relevance of individual factors, refines gene set annotations, and infers factors without annotation. F-scLVM robustly decomposes scRNA-seq datasets into interpretable components, thereby facilitating the identification of novel subpopulations.