Animal Record Keeping Exam 1

Question 1

Mean

Answer 1

x-bar = sum of x divided by n

Question 2

x =

Answer 2

1 observation

Question 3

n =

Answer 3

number of input values

Question 4

median

Answer 4

middle # after put in order

Question 5

mode

Answer 5

most frequent # input

Question 6

Coefficient of Variation

Answer 6

more values = increase variability
CV = s/x-bar

Question 7

standard deviation

Answer 7

fits into the bell curve
have to calc SS, and s2 to get s
take square root of s2

Question 8

Sum of Squares (SS)

Answer 8

(x-xbar)2
total squared deviation from the mean

Question 9

variance (s2)

Answer 9

average squared deviation from the mean
ss/n-1

Question 10

Standard error of the mean (SEM)

Answer 10

accuracy of x
s/square root of n

Question 11

what are the bell curve percentages?

Answer 11

68.26% 1s
95.44% 2s
99.74% 3s

Question 12

z

Answer 12

used for infinite sample size(s)
when degrees of freedom (df) = infinity, z=t
z = x-mean/standard deviation

Question 13

t

Answer 13

adjusted for the size of the sample
defined by df (or v)
smaller sample size = higher value of t

Question 14

degrees of freedom (df)

Answer 14

all samples plus the mean in the calculation so to remove the mean from consideration we use n-1.
It forces us to have at least 2 samples (1 sample does not have variation)

Question 15

what is the difference between s and SEM?

Answer 15

s= standard deviation, fits into the bell curve
SEM = accuracy of x

Question 16

Hints

Answer 16

If given % then look up z in table then mean + or - s(z)
if asked for a percentage then calculate z and look up percent