Deceleration of the trend in Inequality of Education Outcome in the Netherlands
Abstract
The trend in association between highest attained level of education and parental socioeconomic status in the Netherlands, or trend in Inequality of Educational Opportunity (IEO), has been intensely studied in previous Dutch studies. The general conclusion has been of a linear downward trend in IEO over the 20th century. This study will investigate whether this trend is linear by fitting a smooth but flexible local polynomial curve through annual estimates of IEO. The trend (first derivative) and change in trend (second derivative), with confidence envelopes, are calculated from this smooth curve. These confidence envelopes enable one to test at each point in time whether a trend exists, and if so, whether it accelerates or decelerates.
Using 25 surveys harmonized in the International Stratification and Mobility File for the Netherlands with information on annual cohorts between 1930 and 1988 (years refer to the year in which the respondent is 12) showed two periods of significant downward trend for both men (1930-1948 and 1955-1969) and women (1940-1955 and 1963-1976). Females also experienced a period of increasing IEO (1930-1934). The trend was not significantly different from zero outside these periods. The periods of nonsignificant trend at the end of these series were preceded by periods of decelerating trend (1964-1971 for men and 1971-1978 for women), showing that the trend did not became non-significant due to a reduction of power but due to a real slowing down of the trend.