Systematic sampling is a technique where every nth sample is selected from a list to be included in the overall sample. This is useful when subjects are logically arranged like alphabetically or geographically. The procedure is easy to do manually and results are generally representative of the population unless a characteristic repeats every nth individual. To conduct systematic sampling, a starting number and interval are selected, where the interval is the constant difference between consecutive samples. This sampling method is illustrated through an example where every 8th individual is selected from a population of 100 to obtain a sample of 12.

1. FERSIE ANN M. MALACAS
MARINDUQUE NATIONAL HIGH SCHOOL

2. Systematic sampling is a technique of
sampling in which every nth name in a list
may be selected to be included in a sample.
This is used when the subjects or
respondents in the study are arrayed or
arranged in some systematic or logical
manner such as alphabetical
residential or house arrays, geographical
placement from north to south.
S
Y
S
T
E
M
A
T
I

3. The procedure involved in systematic
random sampling is very easy and can be
done manually. The results are
representative of the population unless
certain characteristics of the population are
repeated for every n'th individual, which is
highly unlikely.
S
Y
S
T
E
M
A
T
I
C

4. The process of obtaining the systematic
sample is much like an arithmetic
progression.
Starting number:
The researcher selects an integer that
must be less than the total number of
individuals in the population. This integer
will correspond to the first subject.
S
Y
S
T
E
M
A
T
I
C

5. Interval:
The researcher picks another integer
which will serve as the constant difference
between any two consecutive numbers in
progression. The integer is typically
so that the researcher obtains the correct
sample size
S
Y
S
T
E
M
A
T
I

6. The researcher has a population total of
100 individuals and need 12 subjects.
He first picks his starting number, 5. Then
the researcher picks his interval, 8.
The members of his sample will be
individuals 5, 13, 21, 29, 37, 45, 53, 61, 69, 77,
85, 93.
E
X
A
M
P
L
E
S

7. Lucas's boss wants to send his employees to a
weeklong training session that is out of town.
Due to limited funding, Lucas's boss, Alex,
cannot send all of his employees; he must
choose a group to go to the training. Alex
owns 12 movie theaters and employs 200
people. He has 12 managers out of the 200
employees.
E
X
A
M
P
L
E
S

8. If the population of study contained
2,000 students at a high school and the
researcher wanted a sample of 100 students,
the students would be put into list form and
then every 20th student would be selected for
inclusion in the sample. To ensure against
any possible human bias in this method, the
researcher should select the first individual at
random.
E
X
A
M
P
L
E
S