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In the article “Reproductive Biology of the Aquatic Salamander Amphiuma tridactylum in Louisiana” (Journal of Herpetology [1999]: 100–105). 14 female salamanders were studied. Using regression, the researchers predicted y = Clutch size (number of salamander eggs) from x = Snout-vent length (in centimeters) as follows:
For the salamanders in the study, the
- a. What is the value of the y intercept of the least-squares line?
- b. What is the value of the slope of the least-squares line? Interpret the slope in the context of this problem.
- c. Would you be reluctant to predict the clutch size when snout-vent length is 22 cm? Explain.
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