1. Suppose that the energy research consulting company that you work for has tasked you with determining: Is purchasing premium gasoline better than purchasing regular (unleaded) gasoline? There are many things that you need to consider as you conduct your research. The first thing that you will need to do is to define what you mean by "better" in your research. Then you will need to identify all of the factors/variables that might matter in answering your question - distance travelled, amount of traffic, usual speed limit, type of car, age of car. Also, does price level of each of the types of gasoline matter? What about price differences?
Note that there is no single answer to this question. And you don't want an answer that is so specific that it can't be generalized to other situations. I urge you to think creatively about the question using the data collection concepts discussed in class.
In particular, describe:
a) an ideal randomized (controlled) experiment to answer the question: Is purchasing premium gasoline better than purchasing regular (unleaded) gasoline? (note that I use the term ideal, as it might be an experiment that is ideal but not implementable in the field);
b) an observational cross-sectional data set that would allow you to answer this question (note that this will probably be a primary data set, that you are responsible for collecting);
c) an observational time series data set that would allow you to answer this question (this might be a primary data set, or one that your company uses for other purposes);
d) an observational panel data set that would allow you to answer this question.
2. Read the short article "Will the real unemployment rate please stand up?" which appeared in ScienceDaily on September 10, 2014. Using Course Notes -5 (CN-5) and the discussion of Data and Measurement of Data in class and Lab as background information, respond to the following:
a. Identify and briefly discuss at least fourstatistical concepts presented in the article (e.g., census vs. sample; reliability of a measure over time; etc.)
b. Briefly summarize the conclusions of this article concerning surveys and problems predicting unemployment rates in the US.
3. Work textbook Problem 2.11 (p. 46-47).