Direct Estimation of Batsell and Polking's Model

Batsell and Polking (1985) developed one of the important choice models that address the problem of independence from irrelevant alternatives. In this note, we propose an estimation method that directly estimates Batsell and Polking's model. Compared to the indirect estimation method suggested by Batsell and Polking, the direct method is simpler, making the BP model more accessible to potential users.