I have 14 different type of issues reported by three different mediums (research, newspapers & community). All of them have stressed on few common and few different issues based on frequency or the number of issues recorded in them. Now I wish to compare them to derive most significant issues. But since the total number of data collected for each category is different (either high or low). How do I normalize, compare and then prioritize these data sets proving their statistical significance of major issues along the way?