UNIT ROOTS IN WHITE NOISE

B-Tier
Journal: Econometric Theory
Year: 2012
Volume: 28
Issue: 3
Pages: 485-508

Score contribution per author:

1.005 = (α=2.01 / 2 authors) × 1.0x B-tier

α: calibrated so average coauthorship-adjusted count equals average raw count

Abstract

We show that the empirical distribution of the roots of the vector autoregression (VAR) of order p fitted to T observations of a general stationary or nonstationary process converges to the uniform distribution over the unit circle on the complex plane, when both T and p tend to infinity so that (ln T)/p → 0 and p3/T → 0. In particular, even if the process is a white noise, nearly all roots of the estimated VAR will converge by absolute value to unity. For fixed p, we derive an asymptotic approximation to the expected empirical distribution of the estimated roots as T → ∞. The approximation is concentrated in a circular region in the complex plane for various data generating processes and sample sizes.

Technical Details

RePEc Handle
repec:cup:etheor:v:28:y:2012:i:03:p:485-508_00
Journal Field
Econometrics
Author Count
2
Added to Database
2026-01-26