Question: Since 1985, average mortgage interest rates have
Since 1985, average mortgage interest rates have fluctuated from a low of nearly 3% to a high of over 14%. Is there a relationship between the amount of money people borrow and the interest rate that offered? Here is a scatterplot of Mortgage Loan Amount in the United States (in trillions of dollars) versus yearly Interest Rate since 1985. The correlation is −0.85.
1. Describe the relationship between Mortgage Loan Amount and Interest Rate.
2. If we standardized both variables, what would the correlation coefficient between the standardized variables be?
3. If we were to measure Mortgage Loan Amount in billions of dollars instead of trillions of dollars, how would the correlation coefficient change?
4. Suppose that next year, interest rates were 11% and mortgages totaled $60 trillion. How would including that year with these data affect the correlation coefficient?
5. Do these data provide proof that if mortgage rates are lowered, people will take out larger mortgages? Explain.
6. For these data Kendall tau is -0.65. Does that provide proof that if mortgage rates are lowered, people will take out more mortgages? Explain what Kendall tau says and does not say.
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> A survey was conducted in the United States and 10 countries of Western Europe to determine the percentage of teenagers who had used marijuana and other drugs. The results are summarized in the following table. 1. Create a scatterplot. 2. What is the cor
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> In Exercise 40, you calculated probabilities involving various blood types. Some of your answers depended on the assumption that the outcomes described were disjoint; that is, they could not both happen at the same time. Other answers depended on the ass
> In Exercise 39, you calculated probabilities of getting various M&M. Some of your answers depended on the assumption that the outcomes described were disjoint; that is, they could not both happen at the same time. Other answers depended on the assumption
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> The Mars company says that before the introduction of purple, yellow candies made up 20% of their plain M&M, red another 20%, and orange, blue, and green each made up 10%. The rest were brown. 1. If you pick an M&M at random, what is the probability that
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> Describe a strategy to randomly split 24 tomato plants into the three groups for the completely randomized single-factor experiment of Exercise 4.
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