## Exam (elaborations)

# MATH 225N Week 8 Assignment Correlation Questions-Answers

Question: A scientific study on gerbil population growth results in the data below…. The least squares regression line modeling this data is given by yˆ=13.3 5.567x. What is the slope of the regression line? Round your answer to three decimal places. Question: The scatter plot below shows data for the average cost of a high-end computer (y, in dollars) in the year xyears since 2000. The least squares regression line is given by yˆ=−1677 314x….. A plot of time versus the price of a best-selling model of television has horizontal units of years since 2000 and vertical units of dollars. The best fit line of the data are defined by the equation y=−75x 550, where x=year and y=price…… What are the units of the slope? Question: Which of the following data sets or plots could have a regression line with a negative slope? Select all that apply. Question: Which of the following data sets or plots could have a regression line with a negative y-intercept? Question: Which of the following data sets or plots could have a regression line with a negative y-intercept? Question: Which of the following data sets or plots could have a regression line with a negative slope? Select all that apply. Question: The scatter plot below shows data for the average cost of a high-end computer (y, in dollars) in the year xyears since 2000. The least squares regression line is given by yˆ=−1677 314x….. A plot of time versus the price of a best-selling model of television has horizontal units of years since 2000 and vertical units of dollars. The best fit line of the data are defined by the equation y=−75x 550, where x=year and y=price…… What are the units of the slope? Question: A scientific study on gerbil population growth results in the data below…. The least squares regression line modeling this data is … by yˆ=13.3 5.567x. What is the slope of the regression line? Round your answer to three decimal places. Question: Which of the following data sets or plots could have a regression line with a negative y-intercept? Select all that apply. Question: Which of the following data sets or plots could have a regression line with a negative slope? Select all that apply. Question: The scatter plot below shows data for the cost of a diamond necklace from a department store (y, in dollars) in the year xyears since 2000. The least squares regression line is … by yˆ=1823 314x….. A coordinate system has a horizontal x-axis labeled Year from 4 to 12 in increments of 2 and a vertical y-axis labeled Cost in dollars from 0 to 2000 in increments of 500. A series of 5 plotted points follow the trend of a line segment that rises from l…. Interpret the y-intercept of the least squares regression line. Question: The scatter plot below shows data for the number of sea turtles (y) tagged by scientists in a given year, where xis the year. The least squares regression line is … by yˆ=917,234−444x….. Interpret the y-intercept of the least squares regression line. Question: The scatter plot below shows data for the number of sea turtles (y) observed in the wild in a given year, where xis the year. The least squares regression line is … by yˆ=917,234−444x…… Interpret the slope of the least squares regression line. Question: Which of the following data sets or plots could have a … line with a negative slope? Select all that apply. Question: The scatter plot below shows the average cost of a designer jacket in a sample of years between 2000and 2015. The least squares … line modeling this data is … by yˆ=−4815 765x….. Interpret the slope of the least squares regression line. Question: The scatter plot below shows data for the average cost of a high-end computer (y, in dollars) in the year xyears since 2000. The least squares … line is … by yˆ=−1677 314x….. Interpret the slope of the least squares regression line. Question: Which of the following data sets or plots could have a regression line with a negative slope? Question: A survey regarding truck engines found a positive correlation between the size of the engine and horsepower the engine produces. Answer the following question based only on this information…… True or false: It can … concluded that trucks with larger engines have greater horsepower. Question: Which of the following data sets or plots could have a regression line with a negative y-intercept? Select all that apply. Question: True or False: The more time it takes to travel a road, the longer the road is. Question: A large observational study asks participants about caffeine consumption and sleep duration. The study finds that people with the largest caffeine intake have the shortest sleep duration…… Identify the relation between caffeine consumption and sleep duration.