Machine Learning

I train a classification model to predict coffee reward program membership. The label variable COFFEE has four categories, namely, Starbucks, Peets, Dunkin, and Others. Suppose the current observed label value is Peets. The model returns the following predicted probabilities: Starbucks =0.25, Peets =0.25, Dunkin =0.25, and Others =0.25. What is the sum of squared error for this observation