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Quantitative Research Method . 4.2 Quantitative Research Methods. Uses deductive method of knowledge acquisition Intends to falsifies an existing theory Tries to generate generalizable knowledge Accepts objectivity of knowledge Uses a standard measurement instruments
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4.2 Quantitative Research Methods • Uses deductive method of knowledge acquisition • Intends to falsifies an existing theory • Tries to generate generalizable knowledge • Accepts objectivity of knowledge • Uses a standard measurement instruments • The researcher is independent in the process of knowledge construction • Quantifies the phenomena in terms of numbers • Intends with prediction and controlling
Example - User involvement in system development Success Participation Conflict Conflict resolution Influence Conceptual Framework of User Involvement
Type of quantitative research The purposes of research can be categorized as: • Descriptive (fact finding) • Explorative (looking for patterns) • Analytical (explaining why or how) • Predictive (forecasting the likelihood of particular events)
Descriptive • It started during the Roman Empire • Took census to know the number of people under its empire • Used for taxation purposes • Seeks to accurately describe current or past phenomena - to answer such questions as: • What type of open source software frequently used in Ethiopia? • What type of computers mostly imported in Ethiopia • What are the main software tools used by end users?
Explorative Seeks to understand psychological and sociological phenomena in an effort to find behavioral patterns: • How do users use the new software system? • Why would users use the software in this way contrary to original purpose. For example use of Internet for news rather work related matters • What are the antecedent factors for software project success?
Analytical Seeking to explain the reasons behind a particular occurrence by discovering causal relationships. Once causal relationships have been discovered, the search then shifts to factors that can be changed (variables) in order to influence the chain of causality. Typical questions are: • Do user involvement in software development and users IT skills increase software success? • Does Hardware performance have an influence on software failure?
Predictive • Seeks to forecast the likelihood of particular phenomena occurring in given circumstances. • Does internet bandwidth predict growth online business services ? • Can the new software system increases the organization’s efficiency? • To what extent does new software predict growth of the organization profit? • This compares independent (IV) and dependent variable (DV). • We can predict DV by measuring IV
Experimental Research Design • Used to identify cause and effect relationship • Three types • Pre-experimental design • Quasi experimental • True experimental
Pre-experimental design • A treatment is given for a group at different time and then it is investigated if the treatment brings the change or not • It is relatively weak design as compared the other two Observe Observation Apply treatment
Quasi experimental • The sample are grouped into two groups • Randomization is not considered • Treatment is given for one group and the group or controlled group will not receive the treatment • Measures undertaken on both group to check weather the treatment brings change or not
Quasi … G1 O G2 O X
True experimental • The sample are randomly grouped into two • Treatment is given one group and the other group will not receive the treatment • Measures will be taken to see the Impact of the treatment group
True … G1 O Randomization G2 O X
Method of Data Collection • Structured Interview questions for Face to face or Telephone • Questionnaire • Online questionnaire (there are free sites) • Computer simulation • Computer log files – Data like • Attempts made by Hackers • attempts made to break passwords
Face to face interview • Interviews are fairly structured • The researcher asks standard set of questions and nothing more • Interview is formal and emotionally neutral • The relationship terminated when the interview is completed • It has a distinct advantage of establishing rapport with potential participants and gain cooperation • Yields highest response rate • But time and expense is unaffordable if interviewees are found in different regions and population is large
Telephone Interview • Are less time consuming and less expensive • Can access all participants who has a telephone • Response rate is not as high as face to face interview • But higher than the mailed questionnaire • Sample is biased as it ignores people without telephone • Both has the advantage to clarify ambiguous answers and when appropriate, seek follow up information • Not feasible for large size of population
Guideline for Quantitative interview • Interview should be carefully planned and precisely worded to yield the required data • As you write the questions consider how you can quantify the response, and modify the questions accordingly • Consider asking questions that will elicit qualitative information as well • Restrict each question to a single idea • Save controversial questions for the latter part of the interview
Interview Guide • Select representative sample (interviewees) of the population • Find suitable location to undertake interview • Get written permission • Establish and maintain rapport before interview • Focus on the actual rather than the abstract and hypothetical • Don’t put words in people’s mouths • Keep your reaction to your self • Seek clarifying questions when necessary • Remember that you are not necessarily getting the facts
Questionnaire Survey • Can be sent to large number of people, including those who live thousands of miles away • Researcher does not have contact with the respondents • Helps respondent to freely express their idea than they would be in personal interviews, especially on sensitive and controversial issue
Draw back of questionnaire • Majority of people don’t return • Returned responses may not be a true representative of the originally selected samples • Rely on self report
Questionnaires design • Questionnaires make use of lists and rating scales • Behaviors and attitudes are complex and cannot be easily evaluated and quantified • Check list is a list of behaviors, characteristics or other entities that a researcher is investigating • Either the researcher or participants simply check(s) items from the list • What are features of user friendly software • Graphical interface • Clear navigation direction • Immediate feedback • Other specify ____________
Questionnaire … • A rating scale is more useful when a behavior, attitude, or other phenomena of interest needs to be evaluated on a continuum scale • It is designed with the following scales • “inadequate” to “excellent”, • “never” to “always” or • “strongly disapprove” to “strongly approve”
Guideline for Questionnaire • Keep it short • What do I do with the information? • Is it absolutely essential to have this information to solve part of the research problem • Use simple, clear, unambiguous language • Check for unwarranted assumptions implicit in your questions • How many cigarette do you smoke each day? • Good to add a choice • 25 ___ 25-16 ____ 15-5 ___ <5 ____ None ____ • Word your questions in ways that don’t give clues about preferred or more desirable responses What strategies have you used to try to quit smoking? • Leads him to list strategies he did not try
Guide line … • Check consistency – that leads to give contradictory answer for two questions • Determine in advance how you will code the response • Keep the respondents task simple • Provide clear instructions • Make the questionnaire attractive and professional looking • Conduct a pilot test • Give for half a dozen friends to see they have difficulty understanding any items • Scrutinize the almost final product carefully to make sure it address your needs
Sampling • In descriptive study, the researcher wants to determine the nature of how things are • Describe one or more characteristics of a fairly large population – e.g 3 million • When population is large, select a subset or a sample of the population • Makes conclusion from the sample about the population • Sample must be true representative of the population • Refers to the external validity of a research study
Quantitative Data Analysis • Two types • Descriptive statistics • Used to describe the phenomena with frequency, mean, median, mode • Inferential statistics • This statistics is used to infer about the population from the sample data • T-test to compare means of two groups • Analysis of Variance (ANOVA) • When groups more than two
Analysis • Linear Regression (when the correlation follows the same pattern) • Logistic Regression (when there is linear correlation)