Review the table forecasting a company’s profit based on the number of units sold. Number of Units Profit ($) 500 –10,000 1,200 3,000 2,500 27,000 3,200 40,000 3,600 45,000 4,300 47,000 5,000 45,000 6,750 20,000 Which statement is the best interpretation of the value 29,864 in the quadratic regression equation? The company has an initial loss of about $29,864. The company has an initial profit of about $29,864. The company needs to sell about 29,864 units to break even. The company needs to sell about 29,864 units to maximize its profit.

C) if a country increases its life expectancy, the happiness index will increase or decrease d) if the life expectancy is increased by 4.5 years in a certain country .how much will the happiness index change? Round two decimal places e) use the regression line to predict that happiness index of a country with a life expectancy of 89 years . Round to two decimal places  use the space below to type your answers

B-4 A toy store manager would like to know how the price can affect the sales of toys. In his data, he obtained 100 pairs of prices (unit: £) and volume of sales (unit: hundreds) for the toys. A simple linear regression was run with Sales as the dependent variable and Price as the independent variable with the following results. Regression Statistics R Square Adj. RSqr StErr of EST 0.876 0.767 0.701 4.184 Summary Table Variable Coeff. Std. Err Intercept 64.742 11.310 Price -2.645 0.602 (a) Write down the estimated regression equation. Explain this regression equation. (b) What's the value for R Square? Explain the meaning of this value. (c) Test the significance of the model at a=0.05 level. Write down the hypothesis you are testing, the statistic you use to evaluate the test, and your conclusion. (d) Use the regression output to construct a 99% confidence interval for the predicted sales when the price is set to be 15. (e) A colleague in the toy store claims that £1 increase in the…

2. Participants were kept awake for a certain number of hours before given a visuospatial task. Researchers measured how many correct responses each participant had. Results are shown below. Use alpha = .01. Number of Correct Hours Kept Awake (X) Responses (Y) 21 X = 10 SS, = 422 Y = 10 SS, = 690 2 4 19 %3D 6. 13 SPxy =-525 ху 5 20 S, =5.70 S, = 7.29 9. 11 10 9. 14 5 15 5 17 2 18 1 17 1 13 4 18 8 11 A. Graph the data. B. State the hypotheses. C. Make a decision about the null. a. Calculate Pearson's r i. Decision about null hypothesis? b. Calculate effect size i. Interpret effect size. D. State your conclusion. E. Relate your conclusion to the research. F. Calculate the regression formula. G. If someone was kept awake for 9 hours, what is the predicted number of correct responses?

The value of a sports franchise is directly related to the amount of revenue that a franchise can generate. The accompanying data table gives the value and the annual revenue for 15 major sport teams. Suppose you want to develop a simple linear regression model to predict franchise value based on annual revenue generated.

The cost of a flight is related to the distance traveled: Miles Cost ($) 225 38.5 525 76.1 1,100 119 1,375 142 1,950 200 2,250 244 a)Graph the scatter plot on your calculator. Is the data linear, quadratic, or exponential? b) Use the appropriate regression to find the equation of best fit. c) Use your model to predict the cost of a flight that travels 800 miles? Is this interpolation or extrapolation? d) Use your model to predict the cost of a flight that travels 3000 miles. Is this interpolation or extrapolation?