1.
Assignment On Sampling
Name : Maliha Farha
ID : 191-11-6193

2.
On April 20, 1999, Eric Harris and Dylan Klebold entered Columbine High
School and began shooting teachers and students. Thirteen individuals
died, and the psychological community was again asked to explain such
violent behavior. A psychologist might decide to interview Columbine
students to obtain their perspectives on the factors that motivated the two
young men to commit such a horrendous act. A group of ten students has
already decided to meet and discuss the events of that day. The
psychologist asks if it would be all right to attend the meeting and ask them
some questions. The students agree, and the psychologist records their
thoughts. Based on this information, the psychologist concludes that a
primary reason for the violent behavior was the peer dynamics in the
school that created groups of outcasts.
Critical Thinking Questions
1. Who appears to constitute the population of interest?
Answer –
A “population of interest” is defined as the population/group from which a
researcher tries to draw conclusions. It is a subset of the general population
that the surveyor wants to know more about. Many research studies
require specific groups of interest to make decisions based on their
findings.
Students of Columbine High School are the population of interest here.
2. Which type of sampling procedure best describes that used by the
psychologist?
Answer-
The way a psychologist decided to interview Columbine students and a
group of ten students has decided to meet and discuss the events of that

3.
day that actually refers to voluntary response sampling. Voluntary response
sampling is considered a type of non-probability sampling technique
because participants are self-chosen, and not selected by the researcher on
a random basis.
3. What are the limitations of this sampling method, and in what specific
ways could the sampling method have affected the findings?
Answer-
Limitations:
1.Voluntary response sampling is highly susceptible to bias and yields
unreliable results. Instead, other sampling techniques should be used such
as simple random sampling, stratified random sampling, or even purposive
sampling.
2. Voluntary response sampling is not suited to studies where the aim is to
create unbiased results.
3. Highly biased responses will lead to an extremely low quality of data
collected
4. The researcher doesn’t have control over the composition of a sample.
5.Results are highly susceptible to bias as most respondents who volunteer
have strong opinions on the subject.
The way Voluntary response sampling affected the findings:
The findings were that the violent behavior was the peer dynamics in the
school that created groups of outcasts.

4.
Students of Columbine High School was chosen to respond to surveys
because they have a strong opinion on the subject of the query. This is why
voluntary response samples tend to give rise to significantly biased results,
as most of those who participate will have a strong opinion about a topic in
either direction. Another reason why students are participating is due to
the convenience of joining the query.
The four way it affected the findings -
1. Easy to gather data:
It is easy to find respondents for a voluntary response sample survey as
individuals already have high motivation to respond to the subject of the
study, eliminating the need for the researcher to find respondents.
2.Biased responses:
As members in a voluntary response sample are self-selected volunteers,
they tend to have a stance on the topic that falls in either extreme. This
gives rise to biased and unreliable results.
3.Errors in data quality:
Highly biased responses will lead to an extremely low quality of data
collected.
4. Lack of coverage:
A lack of coverage occurs when members of a population are not
appropriately represented in the sample which happened in the following
case.
That’s how voluntary response sampling affected the findings.

5.
4. What specific steps would you have taken to obtain a representative sample?
Answer-
A representative sample is a group of participants in a study who are, overall,
similar to the broader population under study. Getting a good representative
sample is important for ensuring study validity. The characteristics of the sample
should match the characteristics of the larger population that the researchers
want to investigate.
If I had to obtain a representative sample, I would choose random sampling to
obtain my representative sample.
Steps I would have taken to obtain a representative sample-
Step 1: Define the population
Start by deciding on the population that I want to study.It’s important to
ensure that I have access to every individual member of the population, so
that I can collect data from all those who are selected for the sample.
Step 2: Decide on the sample size
Next, I need to decide how large my sample size will be. Although larger
samples provide more statistical certainty, they also cost more and require
far more work.
There are several potential ways to decide upon the size of sample, but one
of the simplest involves using a formula with desired confidence interval
and confidence level, estimated size of the population I am working with,
and the standard deviation of whatever I want to measure in my
population.

6.
Step 3: Randomly select my sample
This can be done in one of two ways: the lottery or random number
method.
In the lottery method, I would choose the sample at random by “drawing
from a hat” or by using a computer program that will simulate the same
action.
In the random number method, I would assign every individual a number.
By using a random number generator or random number tables, I would
then randomly pick a subset of the population. You can also use the
random number function (RAND) in Microsoft Excel to generate random
numbers.
Step 4: Collect data from my sample
Finally, I would collect data from my sample.
To ensure the validity of my findings, I need to make sure every individual
selected actually participates in my study. If some drop out or do not
participate for reasons associated with the question that I am studying, this
could bias my findings.
So that’s how I would obtain a representative sample.