Concept explainers
In each of Exercises 14.58–14.63,
- a. find the regression equation for the data points.
- b. graph the regression equation and the data points.
- c. describe the apparent relationship between the two variables under consideration.
- d. interpret the slope of the regression line.
- e. identify the predictor and response variables.
- f. identify outliers and potential influential observations.
- g. predict the values of the response variable for the specified values of the predictor variable, and interpret your results.
14.61 Plant Emissions. Plants emit gases that trigger the ripening of fruit, attract pollinators, and cue other physiological responses. N. Agelopolous et al. examined factors that affect the emission of volatile compounds by the potato plant Solanum tuberosum and published their findings in the paper “Factors Affecting Volatile Emissions of Intact Potato Plants, Solanum tuberosum: Variability of Quantities and Stability of Ratios” (Journal of Chemical Ecology, Vol. 26, No. 2, pp. 497–511). The volatile compounds analyzed were hydrocarbons used by other plants and animals. Following are data on plant weight (X), in grams, and quantity of volatile compounds emitted (y), in hundreds of nanograms, for 11 potato plants. For pan (g), predict the quantity of volatile compounds emitted by a potato plant that weighs 75 grams.
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Introductory Statistics (10th Edition)
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- Midgett Co. has accumulated data to use in preparing its annual profit plan for the upcoming year. The cost behavior pattern of the maintenance costs must be determined. The accounting staff suggested that linear regression be employed to derive an equation for maintenance hours and costs. Data regarding the maintenance hours and costs for the last year and the results of the regression analysis are as follows: Month MaintenanceCost Machine Hours Jan. $ 5,000 600 Feb. 3,644 440 Mar. 4,400 610 Apr. 3,337 480 May 5,222 660 June 3,390 410 July 3,618 470 Aug. 5,384 630 Sept. 5,114 590 Oct. 4,883 590 Nov. 3,925 430 Dec. 3,850 350 Sum $ 51,767 6,260 Average $ 4,313.92 521.67 Average cost per hour ($51,767/6,260) = $8.27 (rounded to the nearest cent) r = 0.85977 r2 = 0.73920 The percent of the total variance that…arrow_forwardIn order to determine a realistic price for a new product that a company wants to market the company’s research department selected 10 sites thought to have essentially identical sales potential and offered the product in each at a different price. The resulting sales are recorded in the accompanying table: Price ($) Sales ($1,000s) 15.00 15 15.50 14 16.00 16 16.50 9 17.00 12 17.50 10 18.00 8 18.50 9 19.00 6 19.50 5 h). Estimate the slope of the actual equation of the regression line using a 95% confidence interval and interpret this interval.arrow_forwardFind the slope of the equation of the regression line for the following data: Consumer Price Index 30.2 48.3 112.3 162.2 191.9 197.8 Cost of Pizza 0.15 0.35 1.00 1.25 1.75 2.00arrow_forward
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