`STAT 5050 Homework 5
1. The data set “Kids Age” has ages of kids and their height (in inches). The goal is
to determine how much a kid grows in height per year.
a. Write the null and alternative hypothesis
b. Show the computer output and identify the relevant p-value
c. Determine the validity of your statistical test
d. Write a conclusion
2. A study noted the number of native species on the Galapagos Islands to the total
number of species on them. The goal is to understand the relationship between
these two variables. The number of native species on one of the islands was
missing from the data set (the field technician was surfing that day).
The data are in the file called Galapagos (hint: you will find that both Y and X
need to be log-transformed). The surfing technician has asked you to help him fill
in the missing data value so that he will not get fired, dude.
a)
b)
c)
d)
e)
f)
g)
What is the goal of this project?
What type of statistical test will help you accomplish this?
Explain how you should know that log transformations are needed.
Define the null and alternative hypotheses
Give the computer output and note the relevant p-values
What conclusion can be made from the statistical results?
Explain how to solve the question of interest (from part a)
a. Hint – the answer is not 24
h) Provide a prediction interval for your estimate in part g
a. Hint you will need to transform to the original units
i) Write a paragraph to the client with your response.
3. A study was done to relate lifespan of electrical resistors to the voltage to which
they were exposed. I want an inferential sentence that tells the tale of how the
increase in voltage relates to the decrease in lifespan.
The data are in the Minitab file called voltage.
a. Determine what type of regression is appropriate for this data
b. Justify that your decision for part a is valid.
c. Write out the null and alternative
d. Show the p-value
e. Make a conclusion that explains what you have learned to an electrical
engineer who has not taken a statistics class.