A sample of 300 dentists from Seattle is taken to estimate the median income of
ID: 3020954 • Letter: A
Question
A sample of 300 dentists from Seattle is taken to estimate the median income of all Seattle residents. Is this study
A. REPRESENTATIVE?
B. NON-REPRESENTATIVE?
A simple random sample of 2000 men over age 18 is taken to estimate the mean weight of all adult males. Is this study
A. REPRESENTATIVE?
B. NON-REPRESENTATIVE?
A simple random sample of 2,500 men over the age 18 is taken to estimate the mean height of all adult males. Is this study
A. REPRESENTATIVE?
B. NON-REPRESENTATIVE?
A simple random sample of 1000 voters is taken in order to determine the chances of a certain candidate winning an election. Is this study
A. REPRESENTATIVE?
B. NON-REPRESENTATIVE?
Using a sample of 400 patients from a local hospital, researchers measured cholesterol level in an attempt to estimate the mean cholesterol level of U.S. citizens. Is this study
A. REPRESENTATIVE?
B. NON-REPRESENTATIVE?
Explanation / Answer
REPRESENTATIVE:A subset of a statistical population that accurately reflects the members of the entire population
NON-REPRESENTATIVE:As they are not truly representative, non-probability samples are less desirable than probability samples. However, a researcher may not be able to obtain a random or stratified sample, or it may be too expensive. A researcher may not care about generalizing to a larger population. The validity of non-probability samples can be increased by trying to approximate random selection, and by eliminating as many sources of bias as possible.
1) A sample of 300 dentists from Seattle is taken to estimate the median income of all Seattle residents is representative sample.
2) A simple random sample of 2000 men over age 18 is taken to estimate the mean weight of all adult males is non representative sample. since we are giving more priority to the age 18 above.
3) A simple random sample of 2,500 men over the age 18 is taken to estimate the mean height of all adult males non representative sample. since we are giving more priority to the age 18 above.
4)
A simple random sample of 1000 voters is taken in order to determine the chances of a certain candidate winning an election is representative sample. Since all the 1000 voters are having equal chance to wiln.
5) Using a sample of 400 patients from a local hospital, researchers measured cholesterol level in an attempt to estimate the mean cholesterol level of U.S. citizens.is representative sample.