1. A computer system, comprising: a central processing unit (CPU); a memory device coupled to the CPU; a biometric input device coupled to the CPU; and a computer readable storage device coupled to the processor, wherein the storage device contains program code executable by the CPU via the memory device to implement a method for performing a root cause analysis, said method comprising: opening, by the CPU, a file comprising event data; recording, by the CPU, a user's observable behavior viewing the event data of the file recorded via the biometric input device, wherein the user's observable behavior includes the user's eye gaze; identifying, by the CPU, a presence of one or more events of interest as a function of the user's observable behavior while viewing the event data of the file; calculating, by the CPU, an interest score for each of the identified events of interest, wherein the interest score is a probability of each of the identified events of interest being a root cause of a defect; and tagging, by the CPU, each of the events of interest within the file with a tag as a function of each calculated interest score; wherein said identifying comprises: tracking, by the CPU, a focal point of the user's eye gaze; correlating, by the CPU, the focal point of the user's eye gaze to a viewing position of a display device displaying the file; identifying, by the CPU, as a function of the viewing position, the event data being viewed and an amount of time that the event data is viewed by the user; and further identifying, by the CPU, an emotive expression of the user during an amount of time focused on the viewing position, and wherein said calculating comprises: assigning, by the CPU, a numerical value to the viewing position, amount of time, emotive expression and event data viewed by the user; and inserting, by the CPU, the numerical value assigned to the viewing position, amount of time, emotive expression and text of the event data, into a linear regression model; and outputting, by the CPU, as a function of the linear regression model, a value of the interest score.