A random sample of SAT scores from 39 high schoolers is coll…

A random sample of SAT scores from 39 high schoolers is collected for both the Verbal and Math sections (each is out of 800 points). The five summary descriptive statistics for location and dispersion are provided in the table below, to be used for the next 4 questions. metric verbal math midrange 556 592 mode 580 595 median 592 600 mean 580.51 596.51 trimmean_.2 581.76 597.44 rang 488 400 IQR 204 140 variance 16464.15 10518.89 sd 128.31 102.56 cv 0.22 0.17

During the last 2 months, your department has compared 94 in…

During the last 2 months, your department has compared 94 internal carotid arteries evaluated by carotid duplex with angiography. The results showed 50 vessels had a hemodynamically significant lesion by either method. 40 vessels had no lesion by either method. In 1 case, the noninvasive ultrasound was negative, but the angiogram showed a 70-99% diameter reduction.  In 3 cases, the noninvasive studies were consistent with a >50% diameter reduction, but the invasive study was read as normal. What is the negative predictive value?