MegaProton10791
Applications: 1. A few years ago, it came as a surprise when…
Applications:
1. A few years ago, it came as a surprise when Apple’s iPhone 4 was found to have a problem. Users complained of weak reception, and sometimes even dropped calls, when they cradled the phone in their hands in a particular way. A survey at a local store found that 2% of iPhone 4 users experienced this reception problem. a. Describe the relevant population. b. Is 2% associated with the population or the sample?
2. Many people regard video games as an obsession for youngsters, but, in fact, the average age of a video game player is 35 years old. Is the value 35 likely the actual or the estimated average age of the population? Explain.
3. An accounting professor wants to know the average GPA of the students enrolled in her class. She looks up information on Black-board about the students enrolled in her class and computes the average GPA as 3.29. Describe the relevant population.
4. Recent college graduates with an engineering degree continue to earn high salaries. An online search revealed that the aver-age annual salary for an entry-level position in engineering is $65,000. a. What is the relevant population? b. Do you think the average salary of $65,000 is computed from the population? Explain.
5. Research suggests that depression significantly increases the risk of developing dementia later in life. Suppose that in a study involving 949 elderly persons, it was found that 22% of those who had depression went on to develop dementia, compared to only 17% of those who did not have depression. a. Describe the relevant population and the sample. b. Are the numbers 22% and 17% associated with the population or a sample?
6. Go to www.zillow.com and find the sale price of 20 single-family homes sold in Las Vegas, Nevada, in the last 30 days. Structure the data in a tabular format and include the sale price, the number of bedrooms, the square footage, and the age of the house. Do these data represent cross-sectional or time series data?
7. Go to www.finance.yahoo.com to get the current stock quote for Home Depot (ticker symbol = HD). Use the ticker symbol to search for historical prices and make a table that includes the monthly adjusted close price of Home Depot stock for the last 12 months. Do these data represent cross-sectional or time series data?
8. Go to the New York Times website at www.nytimes.com and review the front page. Would you consider the data on the page to be structured or unstructured? Explain.
9. Conduct an online search to compare small hybrid vehicles (e.g., Toyota Prius, Ford Fusion, Chevrolet Volt) on price, fuel economy, and other specifications. Do you consider the search results structured or unstructured data? Explain.
10. Find Under Armour’s annual revenue from the past 10 years. Are the data considered structured or unstructured? Explain. Are they cross-sectional or time series data?
