Rising mercury levels due to industrial pollution is a recent concern. Many fi sh have high levels of mercury. Data were collected on random samples of tuna from 1991 to 2010 and are available in the file Tuna. Each row in the data set represents the mercury level of a different fish. Do fresh Yellow fin tuna have different levels of mercury on average compared to fresh Albacore tuna? Use the fresh tuna data to answer the following questions.
a. Is this an experiment or an observational study? Explain how you know.
b. Identify the observational units.
c. Identify the explanatory and response variable. Also, identify whether each is quantitative or categorical.
d. Define (in words) the parameters of interest of this study. Also, assign symbols to the parameters.
e. State the null and alternative hypotheses in words as well as using symbols.
f. What statistic will you use?
g. Use an appropriate applet to carry out a simulation analysis. Report the p-value and strength of evidence.
h. Use the 2SD rule to determine a 95% confidence interval. Interpret the interval, making sure it is clear which parameter (in context) the 95% confidence interval is estimating.
i. Give a full conclusion, including significance, estimation, causation, and generalization.