Figure 2From: A three-step approach for the derivation and validation of high-performing predictive models using an operational dataset: congestive heart failure readmission case study Frequencies of the values of gender, emergency department, marital status, and race. The datasets are from 2003–2012, 2008–2012, 2009–2012, and 2013 (6-month). The X axis stands for the values/days of the variable and the Y axis stands for the related frequencies.Back to article page