Rahmi Yamak - Trabzon university
Havvanur Feyza Erdem - Trabzon university

Abstract This study investigates the empirical validity of the variability hypothesis in Turkey for the period of February ۲۰۰۵-November ۲۰۱۵, by using cross-sectional relative price data and by focusing on the assumptions of linearity and stability. The linearity assumption between the two variables is ensured by estimating quadratic regression equation. The assumption of stability is secured by utilizing the Kalman filter approach. The Kalman filter estimates of the regression coefficients suggest that there exists a time varying U-shaped relationship between inflation and cross-sectional relative price variability in Turkey. Time variation on the regression coefficients and the U-shaped curve is significant. The annualized inflation rate which minimizes cross-sectional relative price variability varies from ۸.۷% to ۹.۴%.

Keywords: Inflation, cross-sectional relative price variability, Kalman Filter, U-shape, optimal inflation, time varying coefficient