Problem

The table below lists measured amounts of redshift and the distances (billions of light-years) to randomly selected astronomical objects. Find the (a) explained variation, (b) unexplained variation, and (c) indicated prediction interval. There is sufficient evidence to support a claim of a linear correlation, so it is reasonable to use the regression equation when making predictions. For the prediction interval, use a 90% confidence level with a redshift of 0.0126 .
Unknown environment 'tabular'
a. Find the explained variation.
(Round to six decimal places as needed.)
b. Find the unexplained variation.
(Round to six decimal places as needed.)
c. Find the indicated prediction interval.
billion light-years <y< billion light-years
(Round to three decimal places as needed.)

Answer

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Answer

So, the explained variation is approximately 0.457427, the unexplained variation is approximately 0.000457, and the prediction interval is approximately 0.170 billion light-years <y<0.200 billion light-years.

Steps

Step 1 :First, we calculate the regression line using the given data. The redshift values are [0.0231, 0.0535, 0.0715, 0.0391, 0.0439, 0.0101] and the corresponding distance values are [0.33, 0.76, 1.01, 0.54, 0.61, 0.16].

Step 2 :Using the regression line, we can predict the distance values as [0.33076318, 0.75311012, 1.00318396, 0.55305104, 0.6197374, 0.1501543].

Step 3 :The explained variation is the sum of the squared differences between the predicted distance values and the mean distance value. This is calculated to be approximately 0.457427.

Step 4 :The unexplained variation is the sum of the squared differences between the actual distance values and the predicted distance values. This is calculated to be approximately 0.000457.

Step 5 :For a given redshift value of 0.0126, we can predict the distance to be approximately 0.18488677440679632.

Step 6 :We calculate the t-score for a 90% confidence level to be 2.015048372669157 and the standard error of estimate to be 0.010684052581447383.

Step 7 :The margin of error is calculated to be 0.015040940214386246.

Step 8 :Finally, we calculate the prediction interval by adding and subtracting the margin of error from the predicted distance. This gives us a prediction interval of approximately (0.1698458341924101, 0.19992771462118256).

Step 9 :So, the explained variation is approximately 0.457427, the unexplained variation is approximately 0.000457, and the prediction interval is approximately 0.170 billion light-years \(

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