Before surgical removal of a diseased parathyroid gland, two tests are often performed: the standard intact test and the turbo test. Both tests measure parathyroid hormone (PTH, in ng/l), but the turbo test is very expensive. Researchers obtained data from both tests in a sample of 48 patients to predict turbo test results (y) from standard intact test results (x). The data ranged from roughly 0 to 500 ng/l, and a scatterplot showed a clear linear relationship. The published findings are summarized exactly as follows:
Y = 1.08x - 4.36 (r = 0.97; n = 48)
Roughly what percent of the variation in turbo test results can be explained by this regression model?

Question

Quizplus · Accepted Answer

The coefficient of determination (r^2) is 0.97^2 = 0.9409, which means that 94.09% of the variation in turbo test results can be explained by this regression model.

Before Surgical Removal of a Diseased Parathyroid Gland, Two Tests