# Intro to Probability & Stats

 What sampling method is used? A statistician who makes a research on automobile performance collects information on American, Japanese, and European automobiles separately to combine the results in the end. Stratified What sampling method is used? An inspector team from Department of Education needs to inspect middle schools in a large city. They choose at random 10 schools and then come to each of them to inspect each class. Cluster What sampling method is used? An inspector came to a public school to survey the teachers. She comes to the teacher lounge during the lunch break and talks with every present teacher. Convenience What sampling method is used? A quality control manager picks every 100th soda can, opens it and measures the amount of drink in it. Systematic Is this an observational or an experimental study? A farmer applies several new fertilizers to fruit trees to find out which of them is the most efficient. Experimental Is this an observational or an experimental study? A zoologist counts the bees visiting a rose bush during a 3 - hour period. Observational What level of measurement is this? The letter grades: A, B, C, D, F. Ordinal The data can be arranged in a logical order, but the intervals between them cannot be definded. What level of measurement is this? The number of passengers in a bus. Ratio We can compare the numbers of passengers in different buses by dividing one by the other. What level of measurement is this? Your age. Ratio We can compare two person's ages by dividing one by the other. What level of measurement is this Your year of birth. Interval Years of birth can be compared by subtraction butnot by division, since there is no natural zero. (Each calendar has itdifferent.) What level of measurement is this? Numerical equivalents of school grades (4 for A, 3 for b, 2 for C etc.) Interval Grades can be compared by subtraction, but dividing them by each other makes no sense. What level of measurement is this? The number of teeth in an animals's mouth Ratio We can compare the numbers of teeth by dividing one by the other. What level of measurement is this? A car's maximum speed. Ratio We can compare two car's maximum speeds by dividing one by the other. What level of measurement is this? A girl's hair color. Nominal Colors are always at the nominal level. What level of measurement is this? Your e-mail address What level of measurement is this? Your e-mail address What level of measurement is this? Condition of a knife (sharp, dull, jagged). Ordinal The data can be arranged in a logical order, but the intervals between them cannot be defined. Authorju1iet ID3937 Card SetIntro to Probability & Stats DescriptionFlashcards used created by professor to study chapter 1 Updated2010-01-10T06:06:37Z Show Answers