I have performed a linear regression analysis using R and generated some diagnostic plots by using package DHARMa (in R). However, I am having trouble interpreting these plots and would appreciate any guidance on how to read and understand them.
Brief description of my dataset, variables - 60 teachers were asked to indicate their degree of satisfaction in their work, pay, and opportunities for promotion. Regression analysis with dependent variable - work and independent variable as type of school - state (S) or private (P) - was drawn. I would be grateful if someone could provide a brief explanation of each plot and point out any potential issues that might be visible in the plots, as well as possible solutions or next steps to address those issues.