Cardiologists use the shortrange scaling exponent a1 which m

Cardiologists use the short-range scaling exponent a_1, which measures the randomness of heart rate patterns, as a tool to assess risk of heart attack. The article \"Applying Fractal Analysis to Short Sets of Heart Rate Variability Data\" (M. Pena et al., Med Biol Eng Comput, 2009:709-717) compared values of a_1 computed from long series of measurements (approximately 40,000 heartbeats) with those estimated from the first 300 beats to determine how well the long-term measurement (y) could be predicted the short-term one (x). Following are the data (obtained by digitizing a graph). Compute the least-squares line for predicting the long-term measurement from the short-term measurement. Compute the error standard deviation estimate s. Compute a 95% confidence interval for the slope. Find a 95% confidence interval for the mean long-term measurement for those with short-term measurements of 1.2. Can you conclude that the mean long-term measurement for those with short-term measurements of 1.2 is greater than 1.2? Perform a hypothesis test and report the P-value. Find a 95% prediction interval for the long-term measurement for a particular individual whose short-term measurement is 1.2. The purpose of a short-term measurement is to substitute for a long-term measurement. For this purpose, which do you think is more relevant, the confidence interval or the prediction interval? Explain.

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