I can’t seem to find a definitive answer to this. So, I thought I’d ask here. Is it ideal to include the elbow or not? I’m practicing some previous year question papers for an entrance exam and I came across this question: “If the plot shows a sharp drop from eigenvalue 3.5 to 1.8, followed by a gradual plateau where eigenvalues are 0.9, 0.7, and 0.5. According to the Kaiser-Guttman rule and the Scree plot, how many factors should ideally be retained?” The elbow here would be the second factor, so according to the scree plot rule, should I be retaining 2 factors (i.e. including the elbow) or 1 factor (excluding it). The question also says how many factors should be retained according to both rules. Following the Kaiser-Guttman criteria would mean retaining 2 factors. But if I need to be considering both the rules, should the answer be 1 factor or 2? submitted by /u/musketard3_ [link] [comments]