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You are not logged in. #1 20111108 17:15:57
Statistics Review  Mathematics, Science, Physics, StatisticsUse for Questions 1 and 2 A grocery store takes a random sample of 200 customers. The average checkout time is 4 minutes with a standard deviation of two minutes. 1. The standard error of the mean is? 2. The 95% confidence level for the true average checkout time is? 3. A random sample of 244 observations has a mean of 10, a median of 12 and a mode of 33. The population deviation is known to equal 2.8. the 95.44% confidence interval for the population mean is? 4. The following random sample was collected: 22 33 44 6 The 80% confidence interval for the mean is? 5. A random sample of 200 people was taken. Sixty percent of the people favor President Obama. The 95% confidence interval for the true population of people who favor Obama is? Last edited by malylo (20111108 17:16:49) #2 20111108 17:42:04
Re: Statistics Review  Mathematics, Science, Physics, StatisticsHi;
Let's start at that regression line. What do you know about it? Is it okay to just plug in to the formula? In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 