Question

1. Explain the relationship between sample size and standard error. 2. You have a normal population with a u = 50 and o = 9. You obtain all possible random samples, each with n = 30, from this population and calculate each sample's mean. What will the average value of all the sample means be? a) 50 b) 5.56 c) 30.49 d) Cannot tell without more information 3. You are sampling from a distribution of scores that is positively skewed. You obtain random samples of n = 40 from this population and organize the means of the samples in a distribution. What shape will the distribution of sample means be? a) positively skewed b) negatively skewed c) normal d) bi-modal 4. You have a population with u = 10; you don't know the standard deviation, but you do know the variance, which is 4. If you randomly choose n = 16, what will the standard error be? a) 2 b) 1 c) 0.5 d) 4 5. If we have a normally distributed population with u = 40 and o= 10. If you randomly choose a sample n= 50, what two values cutoff the middle 95% of the distribution of sample means?

Answer 1

solution - リ As som ble size increases, the Standard error reduces - 3119 2) lix= l= 50 3) Normal (By CIT the sample size size] is sufficiently large 4) 2 o =2 4う = so, 1 Standard error GILE VE 2 VIG = 0.5 score Middle 95% of are within a-score I 1.96 So, required range U zo and Mtz 40 - 1.96x 10 50 and 40+1.96x 10 150 37.2 and 42.8