Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
Determining Sample Size1
Glenn D. Israel2
Perhaps the most frequently asked question
concerning sampling is, "What size sample do I
need?" The answer to this question is influenced by
a number of factors, including the purpose of the
study, population siz
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
INTRODUCTION
Meaning of research
Research in common parlance refers to a search for knowledge. One can also define research as a
scientific and systematic search for pertinent information on a specific topic. In fact, research is
an art of scientific inve
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
SAMPLING AND SAMPLING DESIGNS
Algebraically, let the population size be N and if a part of size n (which is < N) of this population
is selected according to some rule for studying some characteristic of the population, the group
consisting of these n unit
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
METHODS OF DATA COLLECTION
The task of data collection begins after a research problem has been defined and research design/
plan chalked out. While deciding about the method of data collection to be used for the study, the
researcher should keep in mind
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
FORMULATION OF RESEARCH OBJECTIVES
The objectives of a research project summarise what is to be achieved by the study. Objectives
should be closely related to the statement of the problem.
General objective
General objectives states what is expected to be
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
RESEARCH DESIGN
A research design is the arrangement of conditions for collection and analysis of data in a
manner that aims to combine relevance to the research purpose with economy in procedure.
In fact, the research design is the conceptual structure w
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
LITERATURE REVIEW
A literature review is an evaluative report of studies found in the literature related to your
selected area. The review should describe, summarize, evaluate and clarify this literature. It
should give a theoretical basis for the researc
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
RESEARCH PROCESS
Research process consists of series of actions or steps necessary to effectively carry out research
and the desired sequencing of these steps.
1. Formulating the research problem:
There are two types of research problems, viz., those whic
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
VARIABLES
Introduction
In Lecture 3, we analysed the problem we wanted to investigate. Now we have come to a stage
where we must ask ourselves the question:
What information are we going to collect in our study to meet our objectives?
This is where a lot
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
TYPES OF DATA
Data comes in various sizes and shapes and it is important to know about these so that the proper
analysis can be used on the data. There are usually 4 scales of measurement that must be
considered:
Ratio Data
Ratio data are continuous data
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
FORMULATION OF HYPOTHESIS
A statement of the problem which is said in a testable form. After extensive literature survey,
researcher should state in clear terms the working hypothesis or hypotheses.
Working hypothesis is tentative assumption made in order
Masinde Muliro University of Science and Technology
Research Methodology
SBL 321

Summer 2015
SCALES OF MEASUREMENT
From what has been stated above, we can write that scales of measurement can be considered in
terms of their mathematical properties. The most widely used classification of measurement
scales are:
Nominal scale: Nominal scale is simp
Masinde Muliro University of Science and Technology
Biostatistics
SBL 311

Summer 2014
SBL 311: Biostatistics
J. C.Korir
Introduction to statistics
Statistics plays a vitally important role in the research. Much of the scientific
information is very often explained in statistical terms, with many decisions in the
Health Sciences being creat