We are receiving a lot of questions about relevant analyses in the Analyse-it Method Validation edition to help in evaluating new diagnostic tests in the fight against COVID-19. Below are some quick links that will help, but contact us if you have questions - we are working as normal.
Also see our latest blog post: Sensitivity/Specificity and The Importance of Predictive Values for a COVID-19 test
A residual plot shows the difference between the measured values and the predicted values against the true values.
The residual plot shows disagreement between the data and the fitted model. The ideal residual plot (called the null residual plot) shows a random scatter of points forming an approximately constant width band around the identity line.