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Formulating Variables. Week 5 Dept. RS & GIS Institute of space technology. Difference between a concept and a variable?. Main difference is measurability Concepts are mental images/perceptions and their meanings vary person to person May or may be measurable Sorrow Tasty Satisfaction. - PowerPoint PPT Presentation
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Variables
Week 5Dept. RS & GISInstitute of space technologyFormulating VariablesDifference between a concept and a variable?Main difference is measurabilityConcepts are mental images/perceptions and their meanings vary person to personMay or may be measurableSorrowTastySatisfaction
Concepts are subjective impressions. 2Value Judgments?Outcomes of our study are excellentThis report is wonderfulWe have developed a good modelThe results shows that this is an outstanding research projectRelationship between these two variables is very weak.All other studies are inferior than this work
Judgments based on our own preferences, indicators and assessment. vary person to person. No uniform yardstick. Simply, a VARIABLE is a measurable characteristic that varies.3Such Judgments without sound basis is not acceptable in research!!!A measuring mechanism is requiredConcepts should be converted into variables for measurementsAny concept that is capable of measurement is a variable.can take on different valuescan take on different values (Kerlinger)
4What is a variable?a concept that can be measureda symbol to which numerals or values are attachedor simply, a variable is something that variesConcepts are highly subjective as an understanding of them varies from person to person and therefore they can not be measured. It is important that the concepts used should be operationalized in measurable terms. 5Examples of concepts & VariablesConceptsVariablesEffectivenessSatisfactionWater QualityExcellentRichenrollments in a programEmployees complaints Bacteria countGPAIncome6It is needed to operationalize concepts into indicators and variables with the goal of limiting the extent of variation in respondents understanding
Operationalize = make measurable7Converting concepts into variablesIdentify indicators criteriaConvert indicators into variablesChoices of indicators may vary with the researcherThere should be a logical link between indicators and their concept
In qualitative research measurements and variables do not carry much significance.
8Table 5.2Example 1: RichFind indicators for wealthExample 2: High academic achievementIndicators???Concepts IndicatorsVariables9Types of variableFrom the view point ofcausal relationshipstudy designunit of measurements
Classification of variables.10From view point of causal relationshipChange variables or Independent variableResponsible for bringing about change in a phenomenon, situation and circumstanceOutcome or Dependent variableEffects, impacts or consequences of a change variableExtraneous (influencing)Affect change in dependent variableIntervening (linking)Establish a relationship/link between independent and dependent variables
11Independent variableon which you have a controlDependent variablevariation in the dependent variable depends on the variation in the independent variablePrecipitationRunoffSunny days in LondonRevenue GeneratedIndependent variables are often also called explanatory variables or predictors. Two variables may be associated but we cannot designate cause and effect. 12
ExtraneousMay increase or decrease the magnitude or strength of a relationship between DV and IV variablesCan not be controlled
3. . . are those factors in the research environment which may have an effect on the dependent variable(s) but which are not controlled. Extraneous variables are dangerous. They may damage a study's validity, making it impossible to know whether the effects were caused by the independent and moderator variables or some extraneous factor. If they cannot be controlled, extraneous variables must at least be taken into consideration when interpreting results.14Intervening Completes the relationship between cause-and-effect variablesSunny days in LondonRevenue GeneratedTourism activities Intelligence education good gradesWorkplace stress physical illness absenteeism Thus, correlation does NOT imply causation. Try to keep intervening variable constant 15Active variablesVariables that can be manipulated, changed or controlledAttribute variablesCan not be manipulated, changed or controlled and that reflect the characteristics of the study populationAgeGenderEducationIncomemotivationEtc.From view point of study designTesting teaching model on which you have control but have no control on students motivation and willingness to participate. However population with certain characteristics (same age) can be selected if randomization is not a requirement)16Categorical/ContinuousQualitative/Quantitative
Very little difference between categorical and qualitative and between continuous and quantitative
From view point of unit of measurementMeasurement ScaleTypes:NominalOrdinalIntervalRatio
Any concept that can be measured on these scales is called a variableDegree of precision in measuring a variable varies from one measurement scale to another
Categorical and QualitativeContinuous and Quantitative18
NominalEach group has a characteristics which is common to all classified within that groupSequence of listing of the subgroups is irrelevant since no relationship between subgroups
Examples:Gender: Male/femaleReligion: Islam/Christianity/HinduTree, house, car, name etc.
http://www.ilearnincambodia.org/rm302/ch5prt2.pdf20Ordinalhas characteristics of a nominal scale PLUS subgroups have relationship to one another arranged in ascending or descending orderRanked according to magnitude but actual magnitude is not quantifiabledistance between categories is not equal, since magnitude is not quantifiable
Example:IncomeAbove averageAverageBelow average
$ 0 1,999$2,000-2,900+$3,000
Age groupsInfantYoungOld
http://www.ilearnincambodia.org/rm302/ch5prt2.pdf21Intervalas ordinal plus an arbitrary starting and ending pointExample:0C is the arbitrary start point with 100 C the arbitrary end pointThe gap is divided into 100 equal spaced intervalsNot an absolute measurement cant say 60C is twice as hot as 30C Cannot perform math calc on each reading, but can do so on differences in readings: 10C hotter today vs. yesterdayhttp://www.ilearnincambodia.org/rm302/ch5prt2.pdf22RatioAll properties of an interval scale plus a fixed starting point e.g. a zero pointExamples:Height in cmFlow volumeProvides an absolute measurement 60 cm is twice as long as 30 cmDifference between intervals is the same and is measured from a zero starting point, therefore can be used for mathematical operations
Table 5.4
http://www.ilearnincambodia.org/rm302/ch5.pdf
25Why it is important to know how a variable is measured?Defines what the type of analysis?Type of applicable statistical procedures?The way the data can be interpreted?How the outcomes can be communicated?Style of your report entirely depends on the way variables are measured way a question has been asked and its response has been recorded
Week 5: Supplementary Notes29Research Objectiveswhat do you want to achieve from your research?closely related to the research problemstate your objectives in clear and concise mannerbreak down into smaller, logically connected parts
30Why objectives are needed?The formulation of objectives will help you to:Focus the study narrowing it down to essentialsAvoid collection of unnecessary datadata which are not strictly necessary for understanding and solving the problem you have identifiedOrganize the study in clearly defined parts or phases
Properly formulated, specific objectives will facilitate the development of your research methodology and will help to orient the collection, analysis, interpretation and utilization of data.30Keep in mind that when the project is evaluatedResults will be compared to the objectives no clear objectives no evaluation!!!!!32How you state your objectives?Cover all aspects of the problemRealisticclearly phrased in operational termsspecifying exactly what you are going to do, where, and for what purposeUse action verbs - specific enough to be evaluated Examples of action verbs are: to determine, to compare, to verify, to calculate, to describe, and to establish. Avoid the use of vague non-action verbs Examples of non-action verbs: to appreciate, to understand, or to study
For action/non-action verbs look at http://www.ctu.edu.vn/guidelines/scientific/thesis/part1/1.4W.htm Properly formulated, specific objectives will facilitate the development of your research methodology and will help to orient the collection, analysis, interpretation and utilization of data.32How to formulate?Brainstorm about your research objectives;Identify your research objectives;Generate general and specific actions;Formulate general and specific research objectives; Do a self-check.
For your help - please look at http://www.ctu.edu.vn/guidelines/scientific/thesis/part1/1.4W.htm
http://www.ctu.edu.vn/guidelines/scientific/thesis/part1/1.4%20research%20objectives.htm3334AbstractWhat does your study or research paper presentWhat was the objective(s) of conducting the studyBrief description of your data (what, when, how)Discuss your model/methodologyConclude your workAvoid; long sentences, spelling and grammatical mistakes, references, footnotes