Movement of avocados into the United States from certain areas is prohibited because of the possibility of bringing fruit flies into the country with the avocado shipments. However, certain avocado varieties supposedly are resistant to fruit fly infestation before they soften as a result of ripening. The data in the table resulted from an experiment in which avocados ranging from 1 to 9 days after harvest were exposed to Mediterranean fruit flies. Penetrability of the avocados was measured on the day of exposure, and the percentage of the avocado fruit infested was assessed.

Use the MINITAB printout of the regression of percentage infected ( y) on days after harvest (x) to analyze the relationship between these two variables. Explain all pertinent parts of the printout and interpret the results of any tests.
MINITAB output for Exercise 12.69
Regression Analysis: Percent versus x
The regression equation is
Percent = 18.4 + 8.18 x

Transcribed Image Text:

Penetrability 91 .81 95 1.04 1.22 1.38 1.77 Days after Harvest Percentage Infected 30 40 45 57 60 75 100 Predictor Constant Coef 18.427 8.1768 SE Coef 5.110 0.9285 3.61 8.81 0.015 0.000 S = 6 . 35552 R-Sq 93.9% R-Sq (adj ) 92.7% Analysis of Variance Source Regression Residual Error Total DF MS 3132.9 3132.9 77.56 0.000 202.0 3334.9 40.4 6