Define Type I and Type II error for each scenario, and identify the cost(s) of each type of error.
a. A 25-year-old ER patient in Minneapolis complains of chest pain. Heart attacks in 25-year-olds are rare, and beds are scarce in the hospital. The null hypothesis is that there is no heart attack (perhaps muscle pain due to shoveling snow).
b. Approaching O'Hare for landing, a British Air fight from London has been in a holding pattern for 45 minutes due to bad weather. Landing is expected within 15 minutes. The fight crew could declare an emergency and land immediately, but an FAA investigation would be launched and other fights might be endangered. The null hypothesis is that there is enough fuel to stay aloft for 15 more minutes.
c. You are trying to finish a lengthy statistics report and print it for your evening class. Your color printer is very low on ink, and you just have time to get to Staples for a new cartridge. But it is snowing and you need every minute to finish the report. The null hypothesis is that you have enough ink.