stats

Question 1

how to find width from histogram

Answer 1

class width/actual width = class width/x

then solve for x

Question 2

how to find height from a histogram

Answer 2

find frequency density ( frequency/ class width)

then FD/actual height = FD/x
solve for x

Question 3

coding with standard deviation

Answer 3

ignore + or - variables
e.g. if code = y=(2x+5)/10
then the standard deviation of y would be coded as 2(standard deviation of x) / 10 (the +5 is omitted)

Question 4

conditions for approximating a binomial distribution

Answer 4

n is large and p is close to 0.5

Question 5

how to convert binomial to normal distribution

Answer 5

mean=np
variance = np(1-p)

continuity corretions-+ or - 0.5 depending on situation

Question 6

what to apply if going from binomial to normal distribution

Answer 6

continuity corrections
+ or - 0.5 depending on what circumstance
basically think about what your answer will round to as you want to include all data points

Question 7

when to use pmcc

Answer 7

-only use pmcc when you are looking at correlation
-if question is a normal hypothesis test compare the value you found to the significance level given