Stats 151 - Estimating population mean from sample mean

Question	Answer
What is P^	Numbers that all lie on a bell curve distribution that are used to predict the structure of a graph
What are the sample proportions?	The estimates of the unknown value p
What is the difference between good and bad estimates of p?	Good values are the values that an close to the centre
What is the parameter	The mean of the population
How do we calculate x bar?	N(u/sigma over Square root of n)
If we want to find the population mean what do we have to find first?	The centre area of the graph or 1 - alpha which is where the good estimates are.
Often you are given 1 - alpha and are aske to find the value of m. How do you do this?	M=Z under script a/2 (sigma/square root of n) sigma is rarely known. If n is greater then 30 we can use standard deviation instead. If n is less then 30 we use t distribution.
What is t distribution.	Same as z distribution but with t instead
What I'd you are given the confidence level. What do you do?	1-a is equal to the confidence level. To find the outer sections use alpha over 2. Add this to your value of alpha to get the area of the big section and one small section together. Use this value to find the z so are and plug it in for Z under script a/2 and solve

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	Created by jennabarnes12387 almost 11 years ago