Concept explainers
Delaying Adulthood. In the paper, “Delayed Metamorphosis of a Tropical Reef Fish (Acanthurus triostegus): A Field Experiment” (Marine Ecology Progress Series, Vol. 176, pp. 25–38), M. McCormick studied larval duration of the convict surgeonfish, a common tropical reef fish. This fish has been found to delay metamorphosis into adulthood by extending its larval phase, a delay that often leads to enhanced survivorship in the species by increasing the chances of finding suitable habitat. Duration of the larval phase for convict surgeonfish is
- a. Sketch the normal curve for the variable x.
- b. Simulate 1500 observations of x. (Note: Users of the TI-83/84 Plus should simulate 750 observations.)
- c. Approximately what values would you expect for the sample mean and sample standard deviation of the 1500 observations? Explain your answers.
- d. Obtain the sample mean and sample standard deviation of the 1500 observations, and compare your answers to your estimates in part (c).
- e. Roughly what would you expect a histogram of the 1500 observations to look like? Explain your answer.
- f. Obtain a histogram of the 1500 observations, and compare your result to your expectation in part (e).
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Introductory Statistics (10th Edition)
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