Why Prediction Interval is Soooooooooooooooo WIDE?
Dears, I was trying to analyze the stability test data. with SCRIPT which was attached in upper Link. However, the PI(Prediction interval) is extremely wide as it is seen as following picture. I have no idea why this happen. Please be aware that if more month of observation is added, PI range drastically reduces. i.e. add 2 more mont