Statistics: Method of Sampling from Data collection method.Population and

1.Method of Sampling from Population
2.Data collection method

1. I.METHODS OF SAMPLING FROM A POPULATION
Sampling is a fundamental aspect of research methodology, enabling researchers to
select a subset of individuals or units from a larger population to make inferences
about that population. The choice of sampling method significantly influences the
validity and reliability of research findings. Below are some of the most widely
recognized and reliable sampling techniques, as discussed in scholarly literature.
1. Random Sampling (Probability Sampling)
This method ensures that every member of the population has an equal chance of
being selected. It minimizes selection bias and enhances the generalizability of the
results. Common types include:
Simple Random Sampling:  Each individual is randomly chosen without
replacement.
Systematic Sampling: Selection occurs at regular intervals (every kth
individual) after a random start.
2. Stratified Sampling
The population is divided into distinct subgroups or strata based on specific
characteristics (e.g., age, gender, income). Random samples are then drawn from each
stratum proportionally, increasing precision and representativeness.
3. Cluster Sampling
The entire population is divided into clusters (e.g., cities, districts). Randomly selected
clusters are then fully surveyed, which is cost-effective, especially for wide
geographical areas.
4. Multistage Sampling
This is a complex form combining multiple sampling methods. For example, clusters
may be selected first, followed by sampling individuals within those clusters, thus
maximizing efficiency.
5. Systematic Sampling
A sampling interval (k) is determined by dividing the population size by the desired
sample size. The starting point is randomly selected, then every kth individual is
chosen.
6. Non-Probability Sampling Methods
While less generalizable, these are useful in certain contexts:
Convenience Sampling: Participants are selected based on availability.

2. Quota Sampling: Ensures that specific quotas (e.g., demographic proportions)
are met.
Purposive (Judgmental) Sampling: Participants are selected based on specific
criteria.
Snowball Sampling: Existing participants recommend others, effective for
hard-to-reach populations.
II.DATA COLLECTION METHODS
Data collection is a critical phase in research, involving systematic procedures to
gather relevant information that addresses the research questions. The choice of data
collection method depends on the research design, objectives, and the nature of data
required. Below are some of the most commonly used data collection methods in social
sciences and public administration research.
1. Surveys and Questionnaires
Surveys involve asking a series of standardized questions to a sample of respondents.
They can be administered in various formats:
Self-administered questionnaires: Distributed physically or electronically
(e.g., online surveys).
Structured interviews: Conducted face-to-face, telephonically, or via online
platforms, with fixed questions.
Advantages:
Cost-effective for large samples.
Enables collection of quantitative data.
2. Interviews
Interviews are face-to-face or virtual communications where researchers ask open-
ended or close-ended questions to gather in-depth information.
Structured interviews: Pre-determined questions.
Unstructured interviews: More flexible and exploratory.
Advantages:
Provides rich, detailed data.
Useful for understanding perceptions and opinions.
3. Observation

3. This method involves systematically watching and recording behaviors, events, or
conditions as they naturally occur.
Participant observation: Researcher actively engages with the subjects.
Non-participant observation: Researcher observes without involvement.
Advantages:
Captures actual behavior, not just reported behavior.
Useful in natural settings.
4. Document and Content Analysis
Involves examining existing documents, records, reports, or media content to extract
relevant data.
Examples: policy documents, reports, censuses, media articles.
Advantages:
Non-intrusive.
Useful for historical or secondary data analysis.
5. Focus Groups
A moderated discussion with a group of participants to explore their perceptions and
attitudes on a specific topic.
Facilitates understanding of group dynamics and collective views.
6. Case Studies
In-depth analysis of a single case or a small number of cases, often combining
multiple data sources.
References
Cohen, L., Manion, L., & Morrison, K. (2018). Research Methods in
Education (8th ed.). Routledge.
Creswell, J. W. (2014). Research Design: Qualitative, Quantitative, and Mixed
Methods Approaches (4th ed.). SAGE Publications.
Yin, R. K. (2018). Case Study Research and Applications: Design and Methods.
SAGE Publications.