SOA Exam SRM Sample Question 31
Study guide: Exam SRM
Determine which of the following indicates that a nonstationary time series can be represented as a random walk
-
I. A control chart of the series detects a linear trend in time and increasing variability.
-
II. The differenced series follows a white noise model.
-
III. The standard deviation of the original series is greater than the standard deviation of the differenced series.
-
A) I only
-
B) II only
-
C) III only
-
D) I, II and III
-
E) The correct answer is not given by (A), (B), (C), or (D).
Answer this question and see the worked solution