What is a sample? What is the difference between sample and population? What are the probability sampling techniques?

1. Sample
INQUIRIES, INVESTIGATION,
IMMERSION

2. Reminder
Raise your hand to speak.
Respect and listen to your classmates.
Respect and listen to your teacher.
Be cooperative.
Wear face mask, practice 2-meter social distancing and sanitize
yourselves using alcohol.
 No monkey business is allowed.

3. Game
Roll a Die
https://eslkidsgames.com/classroom-dice

4. Activity
1. Scan the QR Code provided in order to get the needed information for your assigned
tasks or you may surf the internet for further information .
2. You are going to encode your output in the tablet provided for your group.
3. Send your output in my _______________________ or save the doc in the USB Drive.
4. After 5 minutes, you are going to present your output.
5. Your output will be graded using the rubric.

5. Rubric:
Criteria Exemplary
(5)
Accomplished
(4)
Developing
(3)
Beginning
(2)
No Output
(0)
Content Demonstrates deep
understanding on
the topic.
Demonstrates
understanding on the
topic.
Demonstrates
understanding on
the topic with
some minor error.
Demonstrates
little
understanding on
the topic.
No output
demonstrated.
Reasoning Reasoning is logical,
complete and
accurate.
Reasoning is mostly
logical, complete and
accurate.
Reasoning is
complete but
inaccurate.
Reasoning is
incomplete and
inaccurate.
No reasoning
provided.
Clarity Uses clear, concise
and expressive
language.
Uses clear and
understandable
language.
Uses
understandable
language.
Does not use
clear and
understandable
language.
No output
presented.

6. Activity
Group 1: Differentiate sample and population.
Group 2: Describe Simple Random Sampling, Systematic Sampling,
Stratified Sampling and Cluster Sampling
Group 3: Explain how to solve sample size from a population using
Slovin’s Formula

7. Let’s analyze
 Can we use population instead of sample?
Which is better Simple Random Sampling or
Systematic Sampling?
Which is better Stratified Sampling or Cluster
Sampling?
 What is margin of error?

8. Sample
In research, a SAMPLE is a group of
people, objects, or items that are taken
from a larger population for measurement.
The sample should be representative of
the population to ensure that we can
generalize the findings from the research
sample to the population as a whole.

9. Sample
A sample design is the framework, or
road map, that serves as the basis for the
selection of a survey sample and affects
many other important aspects of a survey
as well.
A sample is just a part of a population.

10. Sample and Population
The population is the entire group that you want to draw
conclusions about.
The sample is the specific group of individuals that you will
collect data from.
The population can be defined in terms of geographical
location, age, income, and many other characteristics.

11. Sample and Population
There are two types of sampling methods:
Probability sampling involves random
selection, allowing you to make strong statistical
inferences about the whole group.
Non-probability sampling involves non-
random selection based on convenience or other
criteria, allowing you to easily collect data.

12. Type of Probability Sampling
1. Simple random sampling
Every member of the population has an equal chance of being selected.
Your sampling frame should include the whole population.
To conduct this type of sampling, you can use tools like random number
generators or other techniques that are based entirely on chance like.
Example
You want to select a simple random sample of 100 employees of
Company X. You assign a number to every employee in the company
database from 1 to 1000 and use a random number generator to select
100 numbers

13. Type of Probability Sampling
2. Systematic sampling
Every member of the population is listed with a number, but instead of randomly generating
numbers, individuals are chosen at regular intervals.
Example
All employees of the company are listed in alphabetical order. From the first 10 numbers, you
randomly select a starting point: number 6. From number 6 onwards, every 10th person on the list
is selected (6, 16, 26, 36, and so on), and you end up with a sample of 100 people.

14. Type of Probability Sampling
3. Stratified sampling
involves dividing the population into subpopulations that may differ in important ways. It allows you
draw more precise conclusions by ensuring that every subgroup is properly represented in the
sample.
To use this sampling method, you divide the population into subgroups (called strata) based on the
relevant characteristic (e.g. gender, age range, income bracket, job role).
Based on the overall proportions of the population, you calculate how many people should be
sampled from each subgroup. Then you use random or systematic sampling to select a sample from
each subgroup.
Example
The company has 800 female employees and 200 male employees. You want to
ensure that the sample reflects the gender balance of the company, so you sort the
population into two strata based on gender. Then you use random sampling on each
group, selecting 80 women and 20 men, which gives you a representative sample of 100
people.

15. Type of Probability Sampling
4. Cluster sampling
 involves dividing the population into subgroups, but each subgroup
should have similar characteristics to the whole sample.
 Instead of sampling individuals from each subgroup, you randomly
select entire subgroups.
Example
The company has offices in 10 cities across the country (all with
roughly the same number of employees in similar roles). You do not
have the capacity to travel to every office to collect your data, so you
use random sampling to select 3 offices – these are your clusters.

16. Slovin’s Formula
The common technique to find the sample size is by using the Slovin’s Formula.
Slovin's formula - is used to calculate the sample size (n) given the population size (N) and a
margin of error (e).
A margin of error tells you how many percentage points your results will differ from the real
population value. The larger the margin of error, the less confidence one should have that
a poll result would reflect the result of a survey of the entire population.

18. Let’s apply! (The same Group)
Given the population, each group will compute for the sample using Slovin formula and describe
the type of probability sampling to be used.
Group 1. Covid-19 affects different people in different ways. Most infected people will develop mild
to moderate illness and recover without hospitalization but need to be quarantined. Here in the
Philippines, Covid-19 spreads very fast. Many people get infected and hospitalized. Due to public
demand, the Department of Science and Technology (DOST) will be conducting a research on the
efficacy of IVERMECTIN to 8,500 mild cases of Covid19 patients using Systematic Sampling with 5
% margin of error.
Group 2. Metacognition is thinking about thinking. It refers to the processes used to plan, monitor
and assess one’s understanding and performance. Teacher X conducts a study to determine the
Metacognitive Skills among Senior High School Students in TDHANMIS. She wanted to use the
Stratified Sampling with 5 % margin of error. Based on the record, there are 63 Grade 12 students
and 160 Grade 11 students.

19. Let’s apply! (The same Group)
Group 3. This year 2021, we will commemorate the Philippine part in the achievement of science and
humankind in circumnavigating the planet for the first time. Central in this commemoration is the 500th
anniversary of the Victory of Mactan on April 27, 2021. These activities are collectively known as the
2021 Quincentennial Commemoration of the Philippines by virtue of Executive Order No. 103. With this,
an Araling Panlipunan teacher of this school would like to conduct a survey among 214 grade 10
students on how knowledgeable they are about the history of the Philippines during the Spanish era. The
teacher would like to use the Simple random sampling with 5 % margin of error.
Group 4. Trees are vital. As the biggest plants on the planet, they give us oxygen, store carbon, stabilize
the soil and give life to the world’s wildlife. In Zamboanga City, there are protected forests with 800
hardword trees particularly in Barangay La Paz particularly in Km. 7,8,9,10, 11, 12, 13 and 14 where
each km has mostly 100 trees. The researchers wanted to study the health of the trees by using cluster
sampling with 5 % margin of error.

20. Click the link or scan the QR
Code for Evaluation
https://docs.google.com/forms/d/16bKiMjArK-_yGzo2X_hEwGD034wi7V6T-WvUms1IUWE/edit

21. Assignment
Answer:
1. How do you write a research sample?
2. Why is data analysis and interpretation important?