Title: CAMPLET: Seasonal adjustment without revisions
Authors: Barend Abeln - Investment consultant (Netherlands) [presenting]
Jan Jacobs - University of Groningen (Netherlands)
Pim Ouwehand - Netherlands Statisitics (Netherlands)
Abstract: The aim is to present a seasonal adjustment program called CAMPLET, an acronym of its tuning parameters, which consists of a simple adaptive procedure to separate the seasonal and the nonseasonal component from an observed time series. Once this process is carried out, there will be no need to revise these components at a later stage when new observations become available. Recently, two most widely used seasonal adjustment methods, Census X12ARIMA and TRAMO SEATS, merged into X13ARIMA SEATS to become a new industry standard. We compare and contrast CAMPLET with X13ARIMA SEATS. The main features of CAMPLET are described, and a brief review of X13ARIMASEATS is provided. We evaluate the outcomes of both methods in a controlled simulation framework using a variety of processes. We apply CAMPLET and X13ARIMA SEATS to three time series: U.S.non farm payroll employment, operational income of Ahold and real GDP in the Netherlands.