Experimental Design and Research Methods.pdf

Experimental Design and Research Methods 09/01/2024 Cletus Adiyaga Wezena(PhD)  Introduction to Research Design Research design:  the conceptual structure within which research is conducted  it constitutes the blue print for the collection, measurement and analysis of d...

Experimental Design and Research Methods 09/01/2024 Cletus Adiyaga Wezena(PhD)  Introduction to Research Design Research design:  the conceptual structure within which research is conducted  it constitutes the blue print for the collection, measurement and analysis of data  provides the back bone structure of the study, it supports the study and hold it's together  refers to the researcher overall plan for answering the research question or testing the research hypotheses.  Introduction to Research Design Process of designing & conducting a research project  What - what was studied?  What about - what aspects of the subject were studied?  What for - what is/was the significance of the study?  What did prior lit./research say?  What was done - how was the study conducted?  What was found?  So what? - what now?  Introduction to Research Design Purposes of research design  It provides the scheme for answering research question.  It maintains control to avoid bias that may affect the outcomes.  It organize the study in a certain way defending the advantages of doing while being aware and caution about potential disadvantages ADVANTAGES  Lead to more accurate results  Give optimum efficiency and reliability  Minimise the wastage of time as well as money  Instills confidence in the research  Provides satisfaction & success.  Introduction to Research Design Components  Title of the study  Abstract  Background and statement of the problem  Justification of the study/hypothesis formulation  Aim and objectives of the study  Review of literature  Methodology and sampling design  Constructing the schedule/Questionnaire  Collection of data  Analysis of data  Discussion/interpretation of results  Conclusion  Time & Financial budgeting  Different Research Design 1. Exploratory type research design 2. Descriptive type research design 3. Experimental type research design Exploratory type research design  also termed as formulative research studies  used for the preliminary investigation of a subject that is not yet well understood or sufficiently researched  serves to establish a frame of reference and a hypothesis from which an in-depth study can be developed that will enable conclusive results to be generated  it relies less on theory and more on the collection of data to identify patterns that explain these phenomena because Because exploratory research is based on the study of little- studied phenomena  Different Research Design Descriptive type research design  the primary objective of descriptive research is to define the characteristics of a particular phenomenon without necessarily investigating the causes that produce it  the researcher must take particular care not to intervene in the observed object or phenomenon, as its behaviour may change if an external factor is involved  a rigid research design that involves probability sampling design, pre-planned design for analysis, structured instruments for collection of data  research design in which the major emphasis is on determining the frequency with which something occurs or the extent to which two variables co vary  Different Research Design Descriptive type research design  enable researcher to describe picture of a phenomenon under investigation  methodology involved is qualitative in nature producing descriptive data and may include these three approaches to enable to record/analyse the bahavioural patterns: i. Participant observation. ii. Personal documents iii. Unstructured interviewing.  Different Research Design Experimental type research design  study in which the investigator manipulates or varies (called the independent variables) and measures other variables (called the dependent variables)  when an experiment is possible it is the most effective method of testing a hypothesis. i.e; one variable ‘X’ casually influences another variable ‘Y’  There are three basic principles of experimental designs: 1. The principle of replication 2. The principle of randomization 3. The principle of local control  Different Research Design Experimental type research design 1.The principle of replication  the experiment should be repeated more than once. thus, each treatment is applied in many experimental units instead of one.  by doing so, the statistical accuracy of the experiments is increased. 2. the principle of randomisation  this provides protection against the effects of extraneous factors by randomisation.  Biase in all forms must be eliminated. 3. the principle of local control  Controls must be part of tests factors  Different Research Design Analytical type of research:  aims to understand phenomena by discovering and measuring causal relations among them  Meaning of Research Design  The problem that follows the task of defining the research problem is the preparation of the design of the research project, popularly known as the “research design”.  Decisions regarding what, where, when, how much, by what means concerning an inquiry or a research study constitute a 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.”  “It is the plan, structure and strategy of investigation conceived so as to obtain answer to research questions and to control variance”  “It is a blue-print for the collection, measurement and analysis of data”  Meaning of Research Design  Research design includes an outline of what the researcher will do from writing the hypothesis and its operational implications to the final analysis of data.  Questions research design address:  What is the study about?  Why is the study being made?  Where will the study be carried out?  What type of data is required?  Where can the required data be found?  What periods of time will the study include?  What will be the sample design?  What techniques of data collection will be used?  How will the data be analysed?  In what style will the report be prepared?  Meaning of Research Design  Research design may be split into the following parts:  The sampling design which deals with the method of selecting items to be observed for the given study  The observational design which relates to the conditions under which the observations are to be made  The statistical design which concerns with the question of how many items are to be observed and how the information and data gathered are to be analysed  The operational design which deals with the techniques by which the procedures specified in the sampling, statistical and observational designs can be carried out.  Meaning of Research Design Features of the research design include:  a plan that specifies the sources and types of information relevant to the research problem.  a strategy specifying which approach will be used for gathering and analysing the data.  a plan of the time and cost budgets since most studies are done under these two constraints.  Different Research Designs 1. Research design in case of exploratory research studies:  the survey of concerning literature  the experience survey 2. Research design in case of descriptive and diagnostic research studies 3. Research design in case of hypothesis-testing research studies  Different Research Designs Research design in case of exploratory research studies:  also known as formulative research study.  The main purpose of such studies is that of understanding a problem for more precise investigation or of developing the working hypotheses  The major emphasis in such studies is on the discovery of ideas and insights.  Generally, the following three methods in the context of research design  Literature survey  Experience survey  the analysis of ‘insight-stimulating’ examples  Different Research Designs Research design in case of descriptive and diagnostic research studies  Descriptive research studies are those studies which are concerned with describing the characteristics of a particular individual, or of a group.  Diagnostic research studies determine the frequency with which something occurs or its association with something else.  The studies concerning whether certain variables are associated are examples of diagnostic research studies.  Different Research Designs Research design in case of hypothesis- testing research studies  Generally known as experimental studies  Are those where the researcher tests the hypotheses of causal relationships between variables.  Such studies require procedures that will not only reduce bias and increase reliability, but will permit drawing inferences about causality.  Usually experiments meet this requirement.  Hence, when we talk of research design in such studies, we often mean the design of experiments. Different Research Designs Different Research Designs  Different Research Designs Cross-sectional Designs:  Involve the collection of information from any given sample of population elements only once.  In single cross-sectional designs, there is only one sample of respondents and information is obtained from this sample only once.  In multiple cross-sectional designs, there are two or more samples of respondents, and information from each sample is obtained only once.  Often, information from different samples is obtained at different times.  Different Research Designs Longitudinal Designs:  A fixed sample (or samples) of population elements is measured repeatedly on the same variables.  A longitudinal design differs from a cross- sectional design in that the sample or samples remain the same over time Qualitative Research:  is primarily exploratory research.  used to gain an understanding of underlying reasons, opinions, and motivations.  it provides insights into the problem or helps to develop ideas or hypotheses for potential quantitative research.  typically include some type of observation, participation, interviewing, and analyses of case studies  Different Research Designs Classification of Qualitative:  Direct Approach  Indirect Approach Direct approach:  One type of qualitative research in which the purposes of the project are disclosed to the respondent or are obvious given the nature of the interview  Focus group : An interview conducted by a trained moderator among a small group of respondents in an unstructured and natural manner. A focus group generally includes 8 – 12 members  Depth interview :An unstructured, direct, personal interview in which a single respondent is probed by a highly skilled interviewer to uncover underlying motivations, beliefs, attitudes, and feelings.  Different Research Designs Indirect approach:  an approach that disguises the true purpose of the project  A projective technique is unstructured, indirect form of questioning that encourages respondents to project their underlying motivation, beliefs, attitudes, or feelings regarding the issues of concern. Quantitative research design:  A research methodology that seeks to quantify the data and, typically, applies some form of statistical analysis.  Involves generation of data in quantitative form which can be subjected to rigorous quantitative analysis in a formal and rigid fashion.  Different Research Designs  Quantitative research is a formal, objective, systematic process in which numerical data are used to obtain information about the world.  This research method is used:  To describe variables  To examine relationships among variables  To determine cause-and-effect interactions between variables Different Research Designs  Different Research Designs Experiment Vs Survey  An experiment refers to an investigation in which a factor or variable under test is isolated and its effect(s) measured.  In an experiment the investigator measures the effects of an experiment which he conducts intentionally.  Survey refers to the method of securing information concerning a phenomena under study from all or a selected number of respondents of the concerned universe.  In a survey, the investigator examines those phenomena which exist in the universe independent of his action Different Research Designs  Different Research Designs Data Collection Methods:  The task of data collection begins after a research problem has been defined and research design prepared.  Research should keep in mind two types of data:  primary data  secondary data  Primary data: these are data which are collected afresh and for the first time.  Secondary data: these are data which have already been collected by someone else and which have already been passed through the statistical process.  Different Research Designs Primary Data Collection:  The primary data are those which are collected first time & thus happens to be in original character.  Primary data is one which is collected by the investigator himself for the purpose of a specific inquiry or study.  There are several methods of collecting primary data:  Observation  Interview Method  Through Questionnaires  Through Schedules  Different Research Designs Data collection through Questionnaires  This method of data collection is quite popular, particularly in case of big enquiries.  It is being adopted by private individuals, research workers, private and public organisations and even by governments.  In this method a questionnaire is sent (usually by post) to the persons concerned with a request to answer the questions and return the questionnaire.  A questionnaire consists of a number of questions printed or typed in a definite order on a form or set of forms.  The questionnaire is mailed to respondents who are expected to read and understand the questions and write down the reply in the space meant for the purpose in the questionnaire itself.  The respondents have to answer the questions on their own.  Different Research Designs  General form Questionnaires can be either structured or unstructured.  Structured questionnaires are those questionnaires in which there are definite, concrete and pre-determined questions.  The questions are presented with exactly the same wording and in the same order to all respondents.  Resort is taken to this sort of standardisation to ensure that all respondents reply to the same set of questions.  The form of the question may be either closed (i.e., of the type ‘yes’ or ‘no’) or open (i.e., inviting free response)  A highly structured questionnaire is one in which all questions and answers are specified and comments in the respondent’s own words are held to the minimum.  When these characteristics are not present in a questionnaire, it can be termed as unstructured or non- structured questionnaire.  Different Research Designs  More specifically, in an unstructured questionnaire, the interviewer is provided with a general guide on the type of information to be obtained, but the exact question formulation is largely his own responsibility and the replies are to be taken down in the respondent’s own words to the extent possible  The questionnaire is generally sent through mail to informants to be answered as specified in a covering letter, but otherwise without further assistance from the sender. The schedule is generally filled out by the research worker or the enumerator, who can interpret questions when necessary.