Rather basic statistics question help please!?
If you're new here, you may want to subscribe to my RSS feed. Thanks for visiting!
The U.S. Federal Trade Commission has recently begun assessing fines and other penalties
against weight-loss clinics that make unsupported or misleading claims about the effectiveness of
their programs. Clinic A claims that the mean weight loss during the first
month is 15 pounds; Clinic B claims a median weight loss of 10 pounds.
a. Assuming the statistics are accurately calculated, which clinic would you recommend if you had
no other information? Why?
b. Upon further research, the median and standard deviation for Clinic A are found to be 10 and 20 pounds, respectively, while the mean and standard deviation for clinic B are found to be 10 and 5, respectively. Describe the two clinics’ weight-loss distributions as completely as possible. Which would you recommend to a prospective client now. Why?
c) What additional information would be important regarding the sampling techniques employed by the clinics?
a) assuming that the government gives fines about the clinics who makes misleading claims I will recommend clinic B because the median is closer to 0 and it’s more probable that clinic A speculate on it’s true median using a large variance to include its numbers..
b) so using a normal table you can find that clinic B
is 10+/- std .deviation * (% safety .found in normal table ) lets say 90% sure so for p=0.9 N=1,96 so 10 +/- 1,96* 5 so that means that clinic be is between (0,2 and 19,8) 90% of the time.of the true mean 10. so it’s pretty sure that one will loose weight.
for Clinic A we have 10+/- 1,96*20 wich lies between (-29,2 and 39,2) so it’s not sure that one will loose weight up there cuz the volatility is way too high.. therefore Clinic B is better
c) the number of clients will definitevly be the turning point more you have people more you are accurate. As the number increase more you are to lie near your real mean!
a) I would go with clinic B. They reported the median, telling me that 50% of clients lose less than 10 lbs and 50% lose more than 10 lbs. The mean given by clinic A could be miss leadings. Say 20 people all lost 7 lbs and five people each lost 47 lbs here 80% of people lost less than 10 lbs at A but the average is higher because of the few big losers.
b) A has a much larger spread of data and a skewed data set where as B has a much more narrow data set and is symmetric. Because of this I would go with B because they produce more consistent results.
c) sample size would be a huge factor in this for determining which clinic does better. Samples are of convenience or random?