Application of Transitional Phase Polynomials to a Model of Trade Union Growth in Canada

The focus of this paper is to motivate the application of transitional phase polynomials to a model of trade union growth in Canada. The advantage and limitations of this approach to capture the effects of a gradual structural change are compared with the more traditional dummy variable technique. Annual time series data for the period 1925-1972 are used to fit the model by least squares. Hypotheses of smooth commencement and smooth convergence of structural change are tested. Highly significant parameter estimates are obtained and the preferred equations are found to be structurally stable.