I want measure the value of a digital engagement, or a digitally engaged customer. Therefore I want to build a model to predict customer value as a function of digital engagement with a given digital asset such as my ipad app. Does anyone have thoughts on how to do this, or know of any literature that discusses appropriate regressors for measuring digital engagement? I am thinking my dependent variable is some measure of customer value (profit - cost to serve) and then my regressors are stages of digital engagement (downloaded App, login daily, login multiple times a day) in addition to demographic variables and I am hoping I can forecast customer value from this.