Slovin's formula is used to determine sample size from a given population. The formula is n=N/(1+Ne^2) where n is the sample size, N is the population size, and e is the desired margin of error. For a population of 9,000 people with a 2% margin of error, the sample size would be 1,957 according to the formula. Stratified random sampling is then used to determine sample sizes from subgroups to ensure representation.

1. DETERMINING THE
SAMPLE SIZE
RICHARD Z. ZONIO
Student

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

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

4. Slovin’S formula in finding the
sample size of the population
N
________
n=
1+Ne2

5. Where:
n = a sample size
N = population size
e = desired margin of error
(% allowance for non-precision because of the
use of sample instead of the population

6. 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:

7. 9000
Example:
______________
n=
1+9000 (0.02)2

8. ___9_0_0_0________
n=
1+9000 (0.0004)

9. ___9_0_0_0____
n=
1+ 3.6

10. ___9_0_0_0____
n=
4.6

11. n = 1,957

12. 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.

13. SAMPLE STUDY

14. DETERMINANTS OF YTHE PERFORMANCE OF
GRADE SIX PUPILS IN THE NATIONAL
ACHIEVEMENT TEST

18. 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

19. Macaingalan ES =
22
______
2084
x 336 = 4
Mascap ES =
63
______
2084
x 336 = 10
Puray ES =
29
______
2084
x 336 = 5

20. Rod. Heights ES =
283
______
2084
x 336 = 46
San Isidro ES =
294
______
2084
x 336 = 47
Tagumpay ES =
238
______
2084
x 336 = 38

24. THANK YOU