(I've been posting a lot of questions b/c I was unable to attend ALL of my stats lectures for my upcoming exam.. I'm not an Idi*t lol I just haven't had the time & really need to hurry up & understand everything. I know it's a lot, but I would really appreciate any help on any of the following questions - thank you!)
1 - as the variablility of scores in pop. increases, the standard error of the mean ________? (decreases/increases/stays the same/flunctuates)
2 - as N increases, the standard error of the mean _____________? (decreases/increases...)
3 - for a normal pop. with a mean = 100 & a standard distribution = 15, which of the following sample means is least likely to be obtained & why? (show work)
a. xbar = 104 for a sample of n =25
b. xbar = 86; n = 4
c. xbar = 105; n = 64
d. xbar = 90; n = 9
4. the mean # of hours Canadians exercise/wk = 2.5, w/ a standard deviation of .55.
what is the standard error of the mean for sample sizes of 30? (show work)
1 - as the variablility of scores in pop. increases, the standard error of the mean ________? (decreases/increases/stays the same/flunctuates)
2 - as N increases, the standard error of the mean _____________? (decreases/increases...)
3 - for a normal pop. with a mean = 100 & a standard distribution = 15, which of the following sample means is least likely to be obtained & why? (show work)
a. xbar = 104 for a sample of n =25
b. xbar = 86; n = 4
c. xbar = 105; n = 64
d. xbar = 90; n = 9
4. the mean # of hours Canadians exercise/wk = 2.5, w/ a standard deviation of .55.
what is the standard error of the mean for sample sizes of 30? (show work)
-
1) increases
2) decreases
3) xbar = 105; n = 64 ( as the sample size increases, sample mean will approach the population mean)
4) Standard error = standard deviation / sqrt(n) = .55 /sqrt(30) = .1004
2) decreases
3) xbar = 105; n = 64 ( as the sample size increases, sample mean will approach the population mean)
4) Standard error = standard deviation / sqrt(n) = .55 /sqrt(30) = .1004