Shalini PrasadAjith RaoEeshoo PING HYPOTHESISANDRESEARCH QUESTIONS500 RESEARCH METHODSSEPTEMBER 18TH 2001
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONS Introduction Processes involved before formulating the hypotheses. Definition Nature of Hypothesis Types How to formulate a Hypotheses inQuantitative ResearchQualitative Research Testing and Errors in Hypotheses Summary
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSThe research structure helps us create research that is :Quantifiable Verifiable Replicable DefensibleCorollaries among the model, common sense & paper formatModelCommon SensePaper FormatResearch QuestionWhyIntroDevelop a TheoryYour AnswerIntroHowMethodIdentify Variables (if applicable)Identify hypothesesExpectationsMethodTest the hypothesesCollect/Analyze dataResultsEvaluate the ResultsWhat it MeansConclusionCritical ReviewWhat it doesn’t MeanConclusion
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSMost research projects share the same general structure, which couldbe represented in the shape of an hourglass.The “Hourglass” notion of researchBEGIN WITH BROAD QUESTIONSNARROW DOWN, FOCUS INOPERATIONALIZEOBSERVEANALYZE DATAREACH CONCLUSIONSGENERALIZE BACK TO QUESTIONS
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSSome of the methods that are included for research formulation are Where does the problem origination or discovery begin?Previous ExperienceTriggered InterestPotential problem fields Criteria of problems and problem statement Goals & Planning Search, Explore & Gather the Evidence Generate creative and logical alternative solutionsMaking the educated guess- the hypothesis!
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSDefinitions of hypothesis “Hypotheses are single tentative guesses, good hunches – assumed for use indevising theory or planning experiments intended to be given a directexperimental test when possible”. (Eric Rogers, 1966) “A hypothesis is a conjectural statement of the relation between two or morevariables”. (Kerlinger, 1956) “Hypothesis is a formal statement that presents the expected relationshipbetween an independent and dependent variable.”(Creswell, 1994) “A research question is essentially a hypothesis asked in the form of a question.”
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSDefinitions of hypothesis “It is a tentative prediction about the nature of the relationship between two ormore variables.” “A hypothesis can be defined as a tentative explanation of the researchproblem, a possible outcome of the research, or an educated guess about theresearch outcome.” (Sarantakos, 1993: 1991) “Hypotheses are always in declarative sentence form, an they relate, eithergenerally or specifically , variables to variables.” “An hypothesis is a statement or explanation that is suggested by knowledge orobservation but has not, yet, been proved or disproved.” (Macleod Clark J andHockey L 1981)
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSNature of Hypothesis The hypothesis is a clear statement of what is intended to be investigated. It shouldbe specified before research is conducted and openly stated in reporting the results.This allows to:Identify the research objectivesIdentify the key abstract concepts involved in the researchIdentify its relationship to both the problem statement and the literature review A problem cannot be scientifically solved unless it is reduced to hypothesis form It is a powerful tool of advancement of knowledge, consistent with existingknowledge and conducive to further enquiry
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSNature of Hypothesis It can be tested – verifiable or falsifiable Hypotheses are not moral or ethical questions It is neither too specific nor to general It is a prediction of consequences It is considered valuable even if proven false
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSAn Example Imagine the following situation:You are a nutritionist working in a zoo, and one of your responsibilities is to develop a menuplan for the group of monkeys. In order to get all the vitamins they need, the monkeys haveto be given fresh leaves as part of their diet. Choices you consider include leaves of thefollowing species: (a) A (b) B (c) C (d) D and (e) E. You know that in the wild the monkeyseat mainly B leaves, but you suspect that this could be because they are safe whilst feedingin B trees, whereas eating any of the other species would make them vulnerable topredation. You design an experiment to find out which type of leaf the monkeys actually likebest: You offer the monkeys all five types of leaves in equal quantities, and observe whatthey eat.There are many different experimental hypotheses you could formulate for the monkeystudy. For example:When offered all five types of leaves, the monkeys will preferentially feed on B leaves.This statement satisfies both criteria for experimental hypotheses. It is a Prediction: It predicts the anticipated outcome of the experiment Testable: Once you have collected and evaluated your data (i.e. observations of what themonkeys eat when all five types of leaves are offered), you know whether or not they atemore B leaves than the other types.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSIncorrect hypotheses would include:When offered all five types of leaves, the monkeys will preferentially eat the type they like best.This statement certainly sounds predictive, but it does not satisfy the second criterion: there is noway you can test whether it is true once you have the results of your study. Your data will showyou whether the monkeys preferred one type of leaf, but not why they preferred it (i.e., they like itbest). I would, in fact, regard the above statement as an assumption that is inherent in the designof this experiment, rather than as a hypothesis.When offered all five types of leaves, the monkeys will preferentially eat B leaves because theycan eat these safely in their natural habitat.This statement is problematic because its second part ('because they can eat these safely in theirnatural habitat') also fails to satisfy the criterion of testability. You can tell whether the monkeyspreferentially eat baobab leaves, but the results of this experiment cannot tell you why.In their natural habitat, howler monkeys that feed in B trees are less vulnerable to predation thanmonkeys that feed on A, C, D, or E.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSThis is a perfectly good experimental hypothesis, but not for the experiment described inthe question. You could use this hypothesis if you did a study in the wild looking at howmany monkeys get killed by predators whilst feeding on the leaves of A, B etc. However,for the experimental feeding study in the zoo it is neither a prediction nor testable.When offered all five types of leaves, which type will the monkeys eat preferentially?This is a question, and questions fail to satisfy criterion #1: They are not predictivestatements. Hence, a question is not a hypothesis.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSTypes of HypothesesNULL HYPOTHESESDesignated by: H0 or HNPronounced as “H oh” or “H-null”ALTERNATIVE HYPOTHESESDesignated by: H1 or HA
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSThe null hypothesis represents a theory that has been put forward, eitherbecause it is believed to be true or because it is to be used as a basis forargument, but has not been proved. Has serious outcome if incorrect decision is made!The alternative hypothesis is a statement of what a hypothesis test is set up toestablish. Opposite of Null Hypothesis. Only reached if H0 is rejected. Frequently “alternative” is actual desired conclusion of the researcher!
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSEXAMPLEIn a clinical trial of a new drug, the null hypothesis might be that the new drugis no better, on average, than the current drug.We would write H0: there is no difference between the two drugs on average.The alternative hypothesis might be that:the new drug has a different effect, on average, compared to that of thecurrent drug.We would write H1: the two drugs have different effects, on average.the new drug is better, on average, than the current drug.We would write H1: the new drug is better than the current drug, on average.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSWe give special consideration to the null hypothesis This is due to the fact that the null hypothesis relates to the statement being tested,whereas the alternative hypothesis relates to the statement to be accepted if /when the null is rejected. The final conclusion, once the test has been carried out, is always given in terms ofthe null hypothesis. We either 'reject H0 in favor of H1' or 'do not reject H0'; we neverconclude 'reject H1', or even 'accept H1'. If we conclude 'do not reject H0', this does not necessarily mean that the nullhypothesis is true, it only suggests that there is not sufficient evidence against H0 infavor of H1; rejecting the null hypothesis then, suggests that the alternative hypothesismay be true.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSFormulating a hypothesis is important to narrow a question down to one that can reasonably be studied ina research project.The formulation of the hypothesis basically varies with the kind of research projectconducted:QUALITATIVEQUANTITATIVE
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSCan also be divided into:TheoryTentative ryHypothesisObservationConfirmation
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSQualitative ApproachThe use of Research Questions as opposed to objectives or hypothesis, is more frequent.Characteristics Use of words- what or how.Specify whether the study: discovers, seeks to understand, explores or describes theexperiences. Use of non-directional wording in the question.These questions describe, rather than relate variables or compare groups. The questions are under continual review and reformulation-will evolve and changeduring study. The questions are usually open-ended, without reference to the literature ortheory. Use of a single focus.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSThe rules of Qualitative researchKleining offers four rules for a scientific and qualitative process of approaching understandingto reality.Rule 1 (refers to subject / researcher)"Prior understandings of the phenomenon to be researched should be seen as provisional andshould be transcended with [the discovery of] new information with which they are notconsistent." (1982: 231)Rule 2 (refers to the object of study)"The object is provisional; it is only fully known after the successful completion of the process ofdiscovery." (1982: 233)Rule 3 (refers to action in relation to the subject of research, hence to data collection)"The object should be approached from "all" sides; rule of the maximum variation ofperspectives." (1982: 234)Rule 4 (refers to the evaluation of information gathered, hence to data analysis)"Analysis of the data for common elements." (1982: 237)
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSQuantitative ApproachIn survey projects the use of research questions and objectives is morefrequentIn experiments the use of hypotheses are more frequentRepresentcomparison between variablesrelationship between variablesCharacteristics The testable proposition to be deduced from theory. Independent and dependent variables to be separated and measured separately. To be either writing-questions, or objectives or hypotheses, but not a combination. Consider the alternative forms for writing and make a choice based on theaudience for the research
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSGeneration of ResearchHypothesisProblem statements becomeresearch hypotheses whenconstructs are operationalizedInitial Ideas(often vague and general)InitialobservationsSearch of existingresearch literatureStatement of the problemOperational definitionsof constructsResearch hypothesis(a specific deductive prediction)
ider the example of a simple association between two variables, Y and X.1. Y and X are associated (or, there is an association between Y and X).2. Y is related to X (or, Y is dependent on X).3. As X increases, Y decreases (or, increases in values of X appear to effect reductionin values of Y).
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONS The first hypothesis provides a simple statement of associationbetween Y and X. Nothing is indicated about the association thatwould allow the researcher to determine which variable, Y or X,would tend to cause the other variable to change in value. The second hypothesis is also a simple statement of associationbetween Y and X, but this time it may be inferred that values of Y arein some way contingent upon the condition of the X variable. The third hypothesis is the most specific of the three. Not only doesit say that Y and X are related and that Y is dependent on X for itsvalue, but it also reveals something more about the nature of theassociation between the two variables.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSTesting & ChallengingThe degree of challenge to the hypothesis will depend on the type of problem andits importance. It can range from just seeking “a good enough” solution to a muchmore rigorous challenge.The term “challenging” may include Verification Justification Refutability Validity Rectification Repeatability FalsificationThere are two possibilities1. Nothing Happenedthe Null Hypothesis - Ho2. Something Happenedthe Alternative Hypothesis - H1
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSHypothesis testing is a four-step procedure:1.Stating the hypothesis (Null or Alternative)2.Setting the criteria for a decision3.Collecting data4.Evaluate the Null hypothesis
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSErrors in HypothesesTwo types of mistakes are possible while testing the hypotheses.Type IType IISmall example:What doc saysYour actual healthsicksickwellYou are sick. Doc confirms itRIGHTDoc missed your real illness!WRONG-Type II error.wellGet scared for nothing!WRONG-Type I errorYou’re really not sick!RIGHT
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSType I Error: A type I error occurs when the null hypothesis (H0) is wrongly rejected.For example, A type I error would occur if we concluded that the two drugsproduced different effects when in fact there was no difference between them.Type II Error: A type II error occurs when the null hypothesis H0, is not rejected when it is infact false.For example: A type II error would occur if it were concluded that the two drugsproduced the same effect, that is, there is no difference between the two drugs onaverage, when in fact they produced different ones.
DEVELOPINGHYPOTHESES&RESEARCHQUESTIONSTo generalize:DecisionReject H0TruthDon't reject H0H0Type I ErrorRight DecisionH1Right DecisionType II Error A type I error is often considered to be more serious, and therefore moreimportant to avoid, than a type II error.
search questions and hypotheses become “signposts” for explaining the purpose of thestudy & guiding the research ”, CreswellA hypothesis is an explanation, tentative and unsure of itself, for specific phenomena aboutwhich you have questions.A well-crafted hypothesis very often suggests the best way to perform the research and givesyou clues as to your research design.There are different types of hypotheses. deductive inductiveResearch Hypothesis can either be non-directional or directional. There exists a hypothesisthat is opposite of the positively stated one, i.e. the null hypothesisThus to conclude it would be fitting to say “hypothesis is perhaps the most powerful tool, manhas invented to achieve dependable knowledge” – Fred Kerlinger
Consider the alternative forms for writing and make a choice based on the audience for the research. DEVELOPING HYPOTHESES & RESEARCH QUESTIONS. Generation of Research Hypothesis. Problem statements become research hypotheses when constructs are