TY - JOUR N2 - This article aims at constructing a new method for testing the statistical significance of seasonal fluctuations for non-stationary processes. The constructed test is based on a method of subsampling and on the spectral theory of Almost Periodically Correlated (APC) time series. In the article we consider an equation of a nonstationary process, containing a component which includes seasonal fluctuations and business cycle fluctuations, both described by an almost periodic function. We build subsampling test justifying the significance of frequencies obtained from the Fourier representation of the unconditional expectation of the process. The empirical usefulness of the constructed test is examined for selected macroeconomic data. The article studies survey indicators of economic climate in industry, retail trade and consumption for European countries. L1 - http://www.journals.pan.pl/Content/103754/PDF-MASTER/mainFile.pdf L2 - http://www.journals.pan.pl/Content/103754 PY - 2013 IS - No 2 EP - 102 DO - 10.24425/cejeme.2013.119255 KW - seasonality KW - almost periodically correlated stochastic processes KW - subsampling KW - business cycle A1 - Lenart, Łukasz A1 - Pipień, Mateusz PB - Oddział PAN w Łodzi DA - 30.06.2013 T1 - Seasonality Revisited - Statistical Testing for Almost Periodically Correlated Stochastic Processes SP - 85 UR - http://www.journals.pan.pl/dlibra/publication/edition/103754 T2 - Central European Journal of Economic Modelling and Econometrics ER -