5. a)For this survey a unit would be the individual fulltime college freshmen. The population would be the all college freshmen. The sample would be the 252,082 freshmen that take part in the survey to represent all college freshmen.
b) This is an example of a stratified random sample because the population is divided into groups, which in this case the groups would be universities, and then a simple random sample is taking from each university.
c) This would be an example of cluster sampling because all colleges and universities represent the clusters and the 464 random samples of clusters are chosen and within those 464 all the first year students were observed.
d) The two sampling methods described in b and c would be easier to implement …show more content…
I would ask anyone who wanted to answer the question. I wouldn’t want to bother someone who his indifferent on the topic. The reason this poll failed is because convenience hinders the accuracy of the study. The opinion taken at convenience cannot represent people who actually have strong thoughts toward the poll. Therefore, the poll is destined to fail due to the fact that such an opinion cannot be extended to the entire population. Quota sampling is not an affective method of sampling because it does not account for changes in physical and geographical aspects.
14. a)The sampling frame for this survey is all the dentists in the nations. There are 66,000 dentists who belong to one of the two magazine subscriptions. However, it does not account for all other dentists who do not have subscriptions to either of the magazines. Therefor, the fact that the survey used a bad-sampling frame led to the inaccurate conclusion.
b) The most serious of the four “difficulties and disasters in sampling” is low response rate because out of all 10,000 there was only 1983 responses. Due to the low response rate the 1983 that did respond cannot be representative of the population. In addition, only dentists who used the product would be likely to respond. Dentists who don’t use the product or are indifferent are not likely to respond to the …show more content…
a) The sample size in this survey should be large enough so that it can encompass the whole population. The sample size if too small can lead to misleading and inaccurate conclusions. The more people surveyed the more accurate the representation of the general population will be.
b) 3% is an excellent random sampling because out of 17,000 people 3% would be 500 people, which is a fairly large sample size.
c) The margin of era is .045 and the sample proportion would be .52. This would make the intervals .475, .565.
Chapter 5: 1, 7, 15, 24, 27
1.In this experiment it would be better to conduct a randomized experiment because the researcher can control the environment in it. For instance in a study where the researcher is trying to see the effects of conditioning, he or she can control confounding variables that could hinder the outcome of the experiment.
7. Here smoking would be called an interactive variable because if the women smoke the rate of heart attacks will in turn increase.
15. a) This study can not be randomized because it is not right to give participants alcohol.
b) Daily drink cuts health is not a justified headline for the study because it is an observational study which means the conclusions of the study cannot be interpreted for the whole
b) This is an example of a stratified random sample because the population is divided into groups, which in this case the groups would be universities, and then a simple random sample is taking from each university.
c) This would be an example of cluster sampling because all colleges and universities represent the clusters and the 464 random samples of clusters are chosen and within those 464 all the first year students were observed.
d) The two sampling methods described in b and c would be easier to implement …show more content…
I would ask anyone who wanted to answer the question. I wouldn’t want to bother someone who his indifferent on the topic. The reason this poll failed is because convenience hinders the accuracy of the study. The opinion taken at convenience cannot represent people who actually have strong thoughts toward the poll. Therefore, the poll is destined to fail due to the fact that such an opinion cannot be extended to the entire population. Quota sampling is not an affective method of sampling because it does not account for changes in physical and geographical aspects.
14. a)The sampling frame for this survey is all the dentists in the nations. There are 66,000 dentists who belong to one of the two magazine subscriptions. However, it does not account for all other dentists who do not have subscriptions to either of the magazines. Therefor, the fact that the survey used a bad-sampling frame led to the inaccurate conclusion.
b) The most serious of the four “difficulties and disasters in sampling” is low response rate because out of all 10,000 there was only 1983 responses. Due to the low response rate the 1983 that did respond cannot be representative of the population. In addition, only dentists who used the product would be likely to respond. Dentists who don’t use the product or are indifferent are not likely to respond to the …show more content…
a) The sample size in this survey should be large enough so that it can encompass the whole population. The sample size if too small can lead to misleading and inaccurate conclusions. The more people surveyed the more accurate the representation of the general population will be.
b) 3% is an excellent random sampling because out of 17,000 people 3% would be 500 people, which is a fairly large sample size.
c) The margin of era is .045 and the sample proportion would be .52. This would make the intervals .475, .565.
Chapter 5: 1, 7, 15, 24, 27
1.In this experiment it would be better to conduct a randomized experiment because the researcher can control the environment in it. For instance in a study where the researcher is trying to see the effects of conditioning, he or she can control confounding variables that could hinder the outcome of the experiment.
7. Here smoking would be called an interactive variable because if the women smoke the rate of heart attacks will in turn increase.
15. a) This study can not be randomized because it is not right to give participants alcohol.
b) Daily drink cuts health is not a justified headline for the study because it is an observational study which means the conclusions of the study cannot be interpreted for the whole