# Question: Exercise 4 46 a Use Equation 4 1 to determine the sample covariance b

Exercise 4.46.

a. Use Equation (4.1) to determine the sample covariance.

b. Use Equation (4.2) and your answer from part (a) to find the regression equation. Compare your result to that found in the specified exercise.

A collection of observations of a variable y taken at regular intervals over time is called a time series. Economic data and electrical signals are examples of time series. We can think of a time series as providing data points (xi, yi), where xi is the ith observation time and yi is the observed value of y at time xi. If a time series exhibits a linear trend, we can find that trend by determining the regression equation for the data points. We can then use the regression equation for forecasting purposes.

a. Use Equation (4.1) to determine the sample covariance.

b. Use Equation (4.2) and your answer from part (a) to find the regression equation. Compare your result to that found in the specified exercise.

A collection of observations of a variable y taken at regular intervals over time is called a time series. Economic data and electrical signals are examples of time series. We can think of a time series as providing data points (xi, yi), where xi is the ith observation time and yi is the observed value of y at time xi. If a time series exhibits a linear trend, we can find that trend by determining the regression equation for the data points. We can then use the regression equation for forecasting purposes.

## Answer to relevant Questions

The U.S. Census Bureau publishes information on the population of the United States in Current Population Reports. The following table gives the resident U.S. population, in millions of persons, for the years 1990-2009. ...y-bar = 2 + x a. Compute the three sums of squares, SST, SSR, and SSE, using the defining formulas (page 164). b. Verify the regression identity, SST = SSR + SSE. c. Compute the coefficient of determination. d. Determine the ...Following are the age and price data for Corvettes from Exercise 4.51: a. Compute SST, SSR, and SSE, using Formula 4.2 on page 167. b. Compute the coefficient of determination, r2. c. Determine the percentage of variation in ...The data from Exercise 4.66 for percentage of gross domestic product (GDP) spent on health care and life expectancy, in years, for selected countries are on the WeissStats CD. Do the required parts separately for each ...Consider the linear equation y = 4 − 3x. a. At what y-value does its graph intersect the y-axis? b. At what x-value does its graph intersect the y-axis? c. What is its slope? d. By how much does the y-value on the line ...Post your question