A camera has been developed to detect the presence of cataract more accurately. Using this camera, the gray level of each point (or pixel) in the lens of a human eye can be characterized into 256 gradations, where a gray level of 1 represents black and a gray level of 256 represents white. To test the camera, photographs were taken of 6 randomly selected normal eyes and 6 randomly selected cataractous eyes (the two groups consist of different people). The
Carry out the test procedure mentioned in Problem 8.28, and report a p-value.
Table 8.14 Median gray level for cataractous and normal eyes
What statistical procedure can be used to test whether there is a significant difference in the median gray levels between cataractous and normal eyes?
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EBK FUNDAMENTALS OF BIOSTATISTICS
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