can be 0 01 p1 x is the character size decimal units such that every character size with smaller decimal units larger character size will be recognized correctly by the patient p2 x is the character size decimal units such that every character size with higher decimal units smaller character size will be recognized incorrectly by the patient model i is the predicted patient observation when modeling the patient va with values at p1 x p2 x the examiner searches for the p1 x and p2 x that their model is best fitting to the real patient observations 1 run over all p1 x and p2 x values and search for the minimum distance between the model and the observations 2 compute the distance from model to observations the model attempts to predict the responses of the patient and hence minimize the wrong predictions of the model distance sum u2225 model p 1 x p 2 x v _array i u2212 r _array i u2225 i 1 n 3 if the computed distance is better lower use the p1 x and p2 x in our model 4 update low and high to be near the estimated va value the method estimates the va value as va_value final_p1 x final_p2 x 2 and the reliability can be measured with the min distance value examples for mathematical models are the first linear model is as follows where s_curve is defined by five points on the plane a1 a2 a3 a4 a5 defining two parabolas functions with internal dependencies the range of s_curve.