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Cointegration and predictability in prereform east European black-market exchange rates

This paper examines the time series properties of the monthly black-market dollar exchange rates of the Bulgarian lev, Czech koruna, East German mark, Hungarian forint, Polish zloty, Rumanian lei and Soviet ruble over the period 1955–1990. All series other than the mark exhibit a unit root in logarithms, and there is evidence of at least two cointegrating vectors linking the remaining rates. Weak exogeneity is rejected for the lev, forint and lei, but strong exogeneity cannot be rejected for the koruna, zloty and ruble, implying causality running from the latter group to the former group, which may be interpreted as reflecting channels of policy interdependence.