determining the sample size

DETERMINING THE SAMPLE

SIZERICHARD Z. ZONIO

Student

It is the small group you observe and a population is the larger group about which your generalization is made

Sample

It is the group to which a researcher would like the results to be generalizable

Population

N

Slovin’S formula in finding the sample size of the population

________

n=

1+Ne2

n = a sample size

Where:

N = population size e = desired margin of error

(% allowance for non-precision because of the use of sample instead of the population

For instance, in your research, if the population is 9,000 and the margin of error you allow is 2%, what is your representative sample?

Through computation, your obtained sample size will be 1,957. This is attained through the following computation:

9000

Example:

______________

n=

1+9000 (0.02)2

9000

______________

n=

1+9000 (0.0004)

9000__________

n=

1+ 3.6

9000__________

n=

4.6

n = 1,957

Always remember that the assumption of a normal distribution of the population should be considered. When the normal approximation of your population is small or poor, this sample size formula does not apply.

SAMPLE STUDY

DETERMINANTS OF YTHE PERFORMANCE OF GRADE SIX PUPILS

IN THE NATIONAL ACHIEVEMENT TEST

Stratified Random Sampling

Amityville ES = 137

______

2084 x 336 = 22

Kasiglahan Vill. ES = 946

______

2084 x 336 = 152

Macabud ES = 72

______

2084 x 336 = 12

Macaingalan ES = 22

______

2084 x 336 = 4

Mascap ES =

63 ______

2084 x 336 = 10

Puray ES = 29

______

2084 x 336 = 5

Rod. Heights ES = 283

______

2084 x 336 = 46

San Isidro ES = 294

______

2084 x 336 = 47

Tagumpay ES = 238

______

2084 x 336 = 38

THANK YOU