Fig. (9) Mutual information between test results, disease status, and pre-TP range. (A) Total mutual information MI_T and its components, the mutual information between test results and the pre-TP range, MI_R , and the mutual information between the test results and disease status, MID , where the brackets indicate the weighted average over all possible values of the pre-TP. These three quantities are related by the sum MI_T = MI_R + MID . Each term can be further broken down into constituents, as illustrated in B and C. (B) Components of the equation for the disease-state related mutual information, MID . The component terms are the change in uncertainty induced by positive and negative test results, UD+ and UD , respectively. The disease-state related mutual information is computed by adding these components together, weighted by the probability of the corresponding test result, denoted t₊ for a positive result, and t_- for a negative test result, i.e. MID=UD+UD+ . (C) Components of the equation for the range-related mutual information, MI_R . The comp onent terms are the change in uncertainty (entropy) that results from positive and negative test re sults, ΔU_R-andΔU_R+ , respectively. The mutual information between the test result and unknown value of the pre-TP (i.e. the range-related mutual information) is computed by adding these components toget her, weighted by the probabi lity o f the corresponding test results, i.e. MI_R = t₊ΔU_R+ + t_-ΔU_R- .