2.11 Quick review questions

A study on the bruising of apples (Doosti-Irani et al. 2016) aimed to determine the relationship between the recorded surface temperature of an apple, and the depth of bruising.

The researchers purposefully hit apples with three different forces (200, 700 and 1200 mJ) to inflict bruises.

The researchers then recorded the depth of the bruising, and recorded the surface temperature at each bruise location.

The study was conducted separately for three different regions of the apple (lower; middle; upper), and each apple was only used once.

  1. The response variable is
  2. The explanatory variable is
  3. What is the best description for the variable 'The location of the bruising'?
  4. True or false: The researchers could minimise the effects of confounding by incorporating potential confounding variables in the anaysis.
  5. True or false: The researchers could use random allocation of the treatments to be applied to the apples to minimise confounding.
  6. True or false: The carry-over effect is likely to be a big problem in this study.
  7. True or false: The Hawthorne effect is likely to be a big problem in this study.
  8. True or false: The placebo effect is likely to be a big problem in this study.
  9. True or false: The observer effect is likely to be a big problem in this study.

References

Doosti-Irani, Omid, Mahmood Reza Golzarian, Mohammad Hossein Aghkhani, Hasan Sadrnia, and Mahboobe Doosti-Irani. 2016. “Development of Multiple Regression Model to Estimate the Apple’s Bruise Depth Using Thermal Maps.” Postharvest Biology and Technology 116: 75–79.