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Agenda. Identification of research questions in quantitative researchFormulation of assumption and hypothesis Sampling of subjects Data collection methods . Formulation of research questions. A research question is simply a hypothesis stated in question formFormulating a research question allows a researcher to conduct more open-ended inquiriesuseful if there is little previous research on the topic a wider range of outcomes can be reported may encourage excessive manipulation of findings30086
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1. Research Seminars inIT in Education(MIT6003)Quantitative Educational Research Design 1 Dr Jacky Pow
2. Agenda Identification of research questions in quantitative research
Formulation of assumption and hypothesis
Sampling of subjects
Data collection methods
3. Formulation of research questions A research question is simply a hypothesis stated in question form
Formulating a research question allows a researcher to conduct more open-ended inquiries
useful if there is little previous research on the topic
a wider range of outcomes can be reported
may encourage excessive manipulation of findings
The research question and hypotheses formulated should be matched
4. Phrasing research questions NO AMBIGUITY! Be specific and straightforward
Avoid vague or nebulous wording
KEEP IT SIMPLE AND FOCUSED! Don’t confuse your readers
5. Phrasing research questions The research question must be testable!
Not so good: Do students with high GPAs feel better about themselves than students with low GPAs?
Better: Do undergraduates with GPAs greater than 3.50 have higher self esteem than undergraduates with GPAs of 1.3 or lower?
6. Assumption and Hypothesis Assumption (2 different uses)
Yet to be verified answer to the question
To set conditions for the research (e.g., the configurations of the students’ home computers are the same)
A hypothesis is a tentative prediction about the nature of the relationship between two or more variables:
A hypothesis represents an educated guess about what will happen in the study
Hypotheses are always held tentatively
7. Hypothesis Hypotheses are simply if-then sentences that can be categorized in certain logical forms, such as no difference (null hypothesis), associated difference, directionality of difference, and magnitude of difference
A good hypothesis implies all these forms in a single sentence, and the trick is to express them as briefly as possible and as simple as possible (e.g. in simple English)
8. Hypothesis All theories contain hypotheses
A single theory can generate many hypotheses
All hypotheses demonstrate inference by concisely reducing extant (existing) knowledge into manageable and meaningful form
Extant knowledge is what you obtain from a literature review
9. Types of hypothesis Null hypothesis
No relationship
Experimental hypothesis
Non-directional
Directional
10. Null Hypothesis Conservative approach to conducting research
Statement of “no relationship” between two variables, or “no difference” between two groups
The null hypothesis is “supported” if the results are non-significant
the null hypothesis is never “proven” (at least not by a single study)
impossibility of proving a negative
11. Experimental hypothesis Prediction of statistically significant findings
significant differences or correlations between groups or among variables
Non-directional hypothesis
significant difference in any direction
Directional hypothesis
significant difference in the predicted direction
12. Non-directional hypotheses If Variable A changes, then Variable B changes, or
There is a relationship between Variable A and Variable B, or
Variable A affects Variable B
13. Directional hypotheses If Variable A increases, then Variable B increases, or
If Variable A decreases, then Variable B decreases
If Variable A increases, then Variable B decreases, or
If Variable A decreases, then Variable B increases
14. Hypothesis examples Null hypothesis:
Ho: The use of ICQ will not increase student’s written communication skill
Non directional hypothesis:
H1: History and Science teachers will differ significantly in their use of IT in their teaching
Directional hypothesis
Ha: Science teachers will use more IT in their class than history teachers
15. Class activity Identify each of the following types of hypothesis:
There are significantly more gifted children in band I schools than in Band II schools
There is no correlation between GPA and salaries 10 years post graduation
There is a correlation between frequency of misconducts and gender
Prolong indulgence in playing computer games will significantly affect children social skills
Experienced primary school teachers will display less negative attitudes toward hyper-active students than inexperienced teachers
16. Developing hypothesis What is the general research question?
What specific hypotheses will you address?
Is it important?
Is it new, exciting, or creative?
How does it fit into the existing literature?
What work have you already done that is relevant?
How can you operationalize the question?
17. Developing hypothesis What are the independent and dependent variables?
What is the design?
Are the measures valid and reliable?
Can you collect the data?
What analyses will you use?
Do you have enough resources?
18. Steps in formulating hypothesis Decide what you want to explain: choose a dependent variable
Your dependent variable must show variation
Run Descriptives to see mean and dispersion statistics
Even better, run Frequencies, and call for a histogram along with the mean and std. dev
19. Steps in formulating hypothesis Choose independent variables that also show variation
One cannot explain variation in a dependent variable with an independent variable that does not vary
e.g., the use of computer in primary 6 cannot be explained by age as age does not vary much in primary 6
20. Steps in formulating hypothesis Think of multiple causes of the dependent variable:
Do two or more independent variables combine to affect it?
Consider using multiple regression to deal with multiple causes
Consider alternative measures of both the dependent and independent variables
21. Steps in formulating hypothesis Does a relationship hold for some units of analysis but not others?
For male but not for female?
For developed nations but not for Third World nations?
For Chinese, but not for Westerners?
Try to develop your analysis so that it considers all the cases, even if the relationship does not apply equally to them
22. Class activities Construct 2 hypotheses in IT in education topic in each of the followings
Non-directional hypotheses
Directional hypotheses
Inverse directional hypotheses
Magnitude with difference hypotheses
23. Variables The basic building blocks of quantitative research are variables. Variables (something that takes on different values or categories) are the opposite of constants (something that cannot vary, such as a single value or category of a variable)
24. Variables Quantitative variables vary in degree or amount (e.g., annual income)
Categorical variables vary in type or kind (e.g., gender)
Independent variables (symbolized by “IV”)
A variable that affects (or is assumed to affect) the dependent variable under study and is included in the research design so that its effect can be determined (e.g., smoking)
25. Variables Dependent variables (symbolized by “DV”)
The variable being affected or assumed to be affected by the independent variable (e.g., lung cancer)
Dependent variables are influenced by one or more independent variables
Intervening variables (also called mediator or mediating variables)
Variables that occur between two other variables. e.g., tissue damage is an intervening variable in the following relationship:
Smoking---->Tissue Damage---->Lung Cancer
26. Class activity For each of the following, indicate the correct variable type by IV for Independent Variable or DV for Dependent Variable:
If use of computer increases as a result of accessibility, then accessibility is what type of variable?
If the general public believe that most hackers are male, then being male is what type of variable?
If the use of ICQ is inversely related to age, then age is what kind of variable?
If the motivation of using a self-learning courseware is a function of the attractiveness of a courseware, then motivation is what type of variable?
27. Class activity - continue If hacking behaviour, mediated by locus of control and lack of appropriate counseling, creates conditions conducive to committing computer crime, then locus of control would be what type of variable?
If the corporate ethics climate and computer crime are associated, then ethics climate is what type of variable?
If the use of illegal copies of computer programs is linked to the convenience of getting them, then the use of illegal copies is what type of variable?
For two groups of pupils, one which is exposed to an educational computer program, and the other which is not, it is shown there are significant differences in learning outcomes, then educational computer program is what type of variable?
28. Sampling of subjects A statistic is a numerical characteristic of a sample
A parameter is a numerical characteristic of a population
29. Sampling size Try to get as big of a sample as you can for your study (minimum = 30)
If the population size is 100 or less, then include the whole population rather than taking a sample
Look at other studies in the research literature and see how many they are choosing
30. Sampling of subjects Probability samples
Simple random sampling
Systematic sampling
Stratified sampling
Non-probability samples
Convenience sampling
Quota sampling
Purposive sampling
31. Simple random sampling Equal chance of selecting (by means of probability) from each member of the population (i.e., equal probability sampling method)
Randomly selected from the list of the population (i.e., sampling frame)
Samples thus selected should contain subjects similar to the population as a whole
Produce “representative” samples
32. Simple random sampling Put all the names from the population into a box and then do a “lucky draw”
Use computer programs to perform
Simple random sampling: Research Randomizer http://www.randomizer.org/
Random assignment of samples http://www.graphpad.com/quickcalcs/randomize1.cfm
Use a random table
33. Systematic sampling A modified form of simple random sampling
Selected systematically rather than randomly
Reorganize the population list (i.e., sampling frame) when combining several ordered lists, to avoid periodicity (i.e., there is a cyclical pattern in the sampling frame)
34. Systematic sampling Determine the sampling interval (k) (i.e., the population size divided by the required sample size)
e.g., Population=3,000; sample=300; k=10
Starting point for the selection is chosen at random from 1 to k
Include every kth element in the sample starting at the number chosen from 2
35. Stratified random sampling Dividing population into homogeneous groups (i.e., stratify the sampling frame)
Each group containing subjects with similar characteristics
Stratified sampling can be proportional or disproportional
e.g., assume the class sizes of 7A and 7B are 40 and 20 respectively, and the desired sampling size is 12
Proportional = 8 from 7A and 4 from 7B
Disproportional = 6 from 7A and 6 from 7B
36. Convenience sampling Choosing the most available or the most easily selected individuals to serve as respondents
Continuing the process until the required sample size is obtained
For example, the pupils or teachers in your school would be convenience samples of your study
37. Quota sampling The non-probability equivalent of stratified sampling
Samples are not selected by probability
Attempts to obtain sample that contains the characteristics of the population
For example, set a quota to each form in your school but the samples are not selected randomly or systematically (just to select the students you know)
38. Purposive sampling Purposely select the samples that the researcher thinks suitable to the study
For example, in studying the student computer usage pattern, you may survey those students who stay in the computer lab after school
39. Response rate No guarantee that the subjects will response to the study (response rate) or providing complete data (quality of response)
A low response rate will affect the validity of the data collected (i.e., data are biased)
The minimum number of response rate differs when surveying a professional population (70%) and the general public (e.g., 50-60%)
Research would need to know the sources of nonresponse and include it in the report if necessary
40. Ways to increase the response rate Perceived reward > perceived cost of responding (in terms of time and effort)
Being consulted on an issue of importance to the subject
Convenience (e.g., self-addressed stamped envelope for returning questionnaires)
Gifts or remuneration (e.g., upon completing a valid questionnaire)
Follow-ups (i.e., reminders)
A must for almost all questionnaire surveys
Should be planned for in advance
Include a realistic time cue in completing the questionnaires
41. Data collection methods Tests
Questionnaires
Quantitative Interviews
Quantitative Observations
42. Tests Standardized tests are used in research to measure the variables (e.g., personality, aptitude, achievement, and performance)
New test will be used to measure the specific knowledge, skills, behavior, or cognitive activity that is being studied
Remember that if a test has already been developed that purports to measure what you want to measure, then you should strongly consider using it rather
43. Strengths of (standardized) tests A wide range of tests is available (i.e. can provide measures of many characteristics of people)
Tests are usually already developed
Consistent (i.e., the same stimulus is provided to all participants)
Strong psychometric properties (high measurement validity)
Allows comparability of common measures across research populations
Availability of reference group data
Can provide “hard,” quantitative data
Ease of data analysis because of quantitative nature of data
44. Weaknesses of (standardized) tests Can be expensive if test must be purchased for each research participant
Test may not be appropriate for a local or unique population
Open-ended questions and probing not available
Tests are sometimes biased against certain groups of people
Nonresponse to selected items on the test
45. Questionnaires A questionnaire is a self-report data collection instrument filled out by subjects
Questionnaires can be
paper-and-pencil instruments
web-based (online)
Remember survey usually use questionnaires but questionnaires are not equal to the ‘survey’
46. 15 Principles of Questionnaire Construction Make sure the questionnaire items match the research objectives
Understand the subjects
The subject (not you) to fill out the questionnaires
Use natural and familiar language
Familiar language is comforting; jargon is not
47. 15 Principles of Questionnaire Construction Write items that are clear, precise, and relatively short
If the subjects do not understand the items, the data will be invalid
Short items are more easily understood and less stressful than long items
Do not use "leading" or "loaded" questions
Avoid double-barreled questions
“Do you acquire the computer skills from classmates and other friends?”
48. 15 Principles of Questionnaire Construction Avoid double negatives
“I disagree that students should not acquire the computer skills on their own.”
Determine whether an open-ended or a closed ended question is needed
In quantitative study, questions are usually closed ended
49. 15 Principles of Questionnaire Construction Use mutually exclusive and exhaustive response categories for closed-ended questions
Mutually exclusive categories do not overlap (e.g., age 0-10, 11-20, 21-30 …)
Exhaustive categories include all possible responses (i.e., include all possibilities)
50. 15 Principles of Questionnaire Construction Consider the different types of response categories available for closed-ended questionnaire items
Rating scale
Numerical rating scales (endpoints are anchored; sometimes the center point or area is also labeled)
Fully anchored rating scales (all the points on the scale are labeled)
It does not matter whether there is a center point (i.e., both 4-point and 5-point scales generally work well)
51. 15 Principles of Questionnaire Construction Rankings (i.e., subjects put their responses into rank order, such as most important, second most important, and third most important)
Semantic differential (i.e., where one item stem and multiple scales, that are anchored with polar opposites or antonyms, are included and are rated by the subjects)
Checklists (i.e., where participants check all of the responses in a list that apply to them)
52. 15 Principles of Questionnaire Construction Use multiple items to measure abstract constructs
To achieve high reliability and validity
To use a summated rating scale (Likert Scale)
53. 15 Principles of Questionnaire Construction Consider using multiple methods when measuring abstract constructs
The use of multiple methods may yield more valid data
Less “method-dependent” (i.e., are the answers corroborated across the methods of measurement or do you get different answers for the different methods?)
54. 15 Principles of Questionnaire Construction Use caution if you reverse the wording in some of the items to prevent response sets
A response set is the tendency of a participant to respond in a specific direction to items regardless of the item content
Develop a questionnaire that is easy for the participant to use
The subjects must not get confused or lost anywhere in the questionnaire
Make sure that the directions are clear and that any filter questions used are easy to follow
55. 15 Principles of Questionnaire Construction Always pilot test your questionnaire
You will always find some problems that you have overlooked
Try best to pilot test with people similar to the subjects to be included in your research study
After pilot testing your questionnaire, revise it and pilot test it again, until it works correctly
56. Strengths of questionnaires Good for measuring attitudes and eliciting other content from research subjects
Relatively inexpensive and quick turnaround
Can administer to probability samples
Can be administered to groups
Perceived anonymity by respondent may be high
Moderately high reliability and validity for well constructed and validated questionnaires
Ease of data analysis
Useful for exploration as well as confirmation
57. Weaknesses of questionnaires Usually must be kept short
Nonresponse to selective items
People filling out questionnaires may not recall important information and may lack self-awareness
Response rate may be low for mail and email questionnaires
Data analysis
New measures need validation
58. Quantitative Interviews Are standardized (i.e., the same information is provided to every subject)
Use closed-ended questions
The key difference between an interview protocol (looks very much like a questionnaire) and a questionnaire is that the interview protocol is read by the interviewer who also records the answers