Assessing change with the extended logistic model

The purpose of this article is to define a method for the assessment of change. A reinterpretation of the extended logistic model is proposed. The extended logistic model for the assessment of change (ELMAC) allows the definition of a time parameter which is supposed to identify whether change occurs during a period of time, given a specific event or phenomenon. The assessment of a trend of change through time, on the basis of the time parameter which is estimated at different successive occasions during a period of time, is also considered. In addition, a dispersion parameter is calculated which identifies whether change is consistent at each time point. The issue of independence is taken into account both in relation to the time parameter and the dispersion parameter. An application of the ELMAC in a learning process is presented. The interpretation of the model parameters and the model fit statistics is consistent with expectations.