The file ibm-d2-dur. txt contains the adjusted durations between trades of IBM stock on November 2, 1990. The file has three columns consisting of day, time of trade measured in seconds from midnight, and adjusted durations.

(a) Build an EACD model for the adjusted duration and check the fitted model.

(b) Build a WACD model for the adjusted duration and check the fitted model.

(c) Build a GACD model for the adjusted duration and check the fitted model.

(d) Compare the prior three duration models.