THE RESEARCH PROCESS

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THE RESEARCH PROCESS
• Type of question(s) asked determine(s) the design:
- qualitative?
- quantitative?
- some of both?
• Design determines analysis
- “hard” = quantitative, (objective);
- “soft” = qualitative, (subjective)
GETTING STARTED: Familiarity with the
Literature
• Goal:What has already been done? Who has done it?
Assists in: - delimiting the research problem
- identifying new approaches and trends
- understanding and identifying methods
Common to all scentific enquiry
Continuum for depth of knowledge
II
passing knowledge
thorough, in-depth
knowledge
FAMILIARITY with the LITERATURE
• SOURCES
- Indices, e.g. Education
Index, Psych Abstracts,
Science Citation Index
- On-line search e.g.
ERIC, Psych Abs., author
name
- Dissertations etc. e.g.
Diss. Abs. Intl. and local
- Bibliographies -Books,
popular literature etc.
• ACTION
- be open-minded
- work backwards
- contrast sources and type
of knowledge
- evaluate content over
style: beware ‘common
knowledge’
- keep review up-to-date
- synthesise and reference
HOW to IDENTIFY a RESEARCH
QUESTION(s)
• OBSERVE
- e.g. what determines
student behaviour/unit
status in a given situation?
- e.g. why is particular
experiment/methodology
less-than-satisfactory?
- what can be learned by
studying current practice?
- why are some
topics/measurements
difficult to learn/make?
• DERIVE
- inspiration from published
work, e.g., seek to verify,
replicate, refute
- apply (existing) theory to
(your) practice
- resolve conflicting or
contradictory findings
- correct methodology in
earlier work
TOPIC CHOICE
• AVOID
- Unresearchable Topics
Is the topic amenable to
data collection and
analysis?
-Trivial Topics
Relevance?
- Overworked Topics
Do you have a new slant?
• CONSIDER
- Personal Factors
Interested? Unbiased?
Background and skills?
Equipment, tools,
participants, TIME?
- General Factors
Will the DATA be
adequate, applicable,
new, worth having?
PROBLEM FORMULATION/
Some Common Mistakes
• Poor definition of context - lack of theoretical or
conceptual framework
• Poor Basis - unsupported claims and assumptions
• Data Collection- without defined purpose
• Fitting Questions - to a “batch” of data
• Poor Review of professional literature
• “One-Shot” research - conducting research unique to a
given situation, permitting no expansion/generalisation
• Failure to make assumptions explicit, recognise limtations
in approach, anticipate alternative explanations.
COMMON ERRORS in SELECTION
• Availability - not “convenient” to sample/randomize
• Population - not defined correctly (selecting
participants/measuring units which are not appropriate)
• Ignoring Design or MODEL - in obtaining sample,
implementing conditions.
• Compromising - too soon/not exploring the implications.
• Volunteers/Common knowledge - what distinguishes
volunteers from “non-volunteers”/ how good is common
knowledge?
• Size - too small/insufficient detail - attrition
DESIGN - THE DATA PROBLEM
-what are the issues?
Questions  Design  Data  Analysis
• Type of questions being asked?
• Logistics - size, feasibility etc.
• Depth of knowledge?
E.g. model assumptions, functional forms
• Sourcing data - what are the difficulties? What are the key
variables? Is it realistic/valid to generate data - what
checks are built in?
THE APPROACH
Qualitative
• exploratory
• undirected
• investigator - “instrument”
• bias of investigator must
be considered
• subjective
• analysis less formal, but
hard to define - need a
methodology
Quantitative
• verify, refute: “evidence”
• shape/hypotheses - a priori
• investigator neutral
• investigator unbiased
• objective
• formal analysis
STUDY DESIGN:
Establishing Goals and Limitations
• Qualitative
- Estimate time needed
- how do you expect design
to emerge from
exploration you propose?
- how many is enough?
- what data will be initially
collected? How will you
handle data evolution?
- topic, theory, methodology
intertwined
• Quantitative
- Estimate time needed
- formulate hypotheses
- define variables
-internal/external validation
-select participants
- determine design which
enables hypotheses to be
tested
- fixed at start/ reproducible
GENERATING/COLLECTING DATA
MODE
1. Observation e.g. objective measurement or tally,
evaluation of participants
2. Development e.g. quality metrics/tests/validation
3. Survey - both quantitative/qualitative. Data collection
Records
Interviews
Questionnaires
(accuracy?) (content/technique)
(design)
3. Case Study - useful if context critical, but analysis
convoluted - heuristic results/multiple sources
4. Simulation - probabilistic/deterministic- assumptions vital
TIPS for ANALYSIS of QUALITATIVE DATA
• Devise plan for sorting through and organising large
amounts of material
• Analysis may require numerical aspects - see earlier
• REMEMBER - tends to be heavily subjective; do not claim
more than the data or design allow.
• Abstract from the data to determine logical organisation
e.g. if analysing a videotape, say, might “Identify” major
theme shown by results, illustrate with actual data, but do
not suppress adverse data, set up a multi-category
encoding form, review tape action at specified intervals.
TIPS for ANALYSIS of QUANTITATIVE DATA
• Keep it simple for exploration, but focus on hypotheses
• Ensure software used is validated/interpretable
• a range of possible techniques? Do not be afraid to use
them. What are the assumptions underlying them? Think
ahead at the design stage. Comparison important? Have
you ensured equal precision?
• Statistical inferences important? Non-parametric (smalkl
numbers) vs parametric. Make sure estimating/testing
what you set out to. What does significance imply?
• Conclusions - relevant to questions posed?
ASSESSING THE QUALITY OF
WHAT YOU DO - I
• DATA ANALYSIS - Is it relevant and correct for the
DESIGN you have chosen? Have you succeeded e.g. in
-identifying relationships/making predictions, obtaining
correlations, describing causal patterns, disclosing
differences (if these exist) between participants or groups
or “treatments” or in substantiating that they do not?
- is your evaluation of a method, programme or product
comprehensive, able to stand up to further testing?
- are your results reproducible, can they be expanded upon,
do they add significant knowledge?
ASSESSING THE QUALITY OF
WHAT YOU DO - II
Internal Validity how consistently can similar results be obtained for e.g.
the participants, the setting, using simular techniques?
• External Validity are the results representative of the “world-at-large”
• Data Verification
e.g. replication (multiple data), e.g. riangulation (multiple
perspectives)
ASSESSING THE QUALITY OF
WHAT YOU DO - III
THE THREATS TO VALIDITY
• QUALITATIVE
- Internal Consistency
(obtain independent
comparisons/retain
evidence)
- credibility
- trustworthiness
- neutrality/bias?
- extrapolation
• QUANTITATIVE
- History/maturation
- measurement changes,
e.g. change of
observer/scorer
- incorrect selection/bias
- missing data
-real group differences
(say) - not due to study
WHAT ARE KEY SUMMARY POINTS?
• Background
- major questions asked
- conceptual basis/theory behind study
- nature of the research/design
• Research Methodology
- characteristics of participants
- procedures for selection of participants
- characteristics of experiment
- data collection tools and techniques
(continued)
(continuing) SUMMARY POINTS
• Results/Conclusions/Reactions
- data reduction techniques, (e.g. statistical analysis)
- interpretation of results and important comments of author
- major conclusions and recommendations
- implications of the findings
- your reactions to aspects of study
e.g. study rationale, conduct of study, data analysis or
measurement used, researcher’s conclusions, other aspects
of study design, relevance in context
SUPPLEMENT
The following are supplementary to the first talk,
and give a few pointers/ references for a
quantitative approach using small numbers and
non-parametrics/distribution-free techniques
NUMBERS and APPROACH
• QUALITATIVE
- widest “variety” possible
- plans for data collection
will influence selection
e.g. choose other people’s
students
e.g. include quantitative
- plan use of all data
collected and cross-checks
• QUANTITATIVE
- define population
what is the target
population?
- sample definition and
compromises??
Implications?
- varied data type / nonparametrics vs parametrics
Non-parametrics/Distribution Free
-fewer assumptions/ ‘Quick and Dirty’
ABUSING e.g. STUDENT t -TEST common in
parametric statistics/Estimate (and the rest)
- non-normality (may be obvious, may be because sample
sizes are too small to establish distributional basis)
- type of data less sophisticated in N-P (may be
proportions or counts, may be measurements on ordered
categories e.g.--, -,0, +,++)
- parameters not of intrinsic interest (not interested in
values of parameters or differences or ratios , but e.g.
properties such as independence, randomness, ranking
- parametric less useful than NP if conditions wrong
EXAMPLES
• Scores recorded for 10 children on two subjects (Sign Test)
A 19 11 14 17 23 11 15 19 11 8
Note: r = +ve = 4
B
22 18 17 19 22 12 14 11 19 7
s = -ve =6
- - - - + - + + - +
r, s ~B(10, 0.5)
For 2-sided test, 2Pr {r  4} = 0.75, so A and B results same
• Students ranked as shown: (Spearman’s )
Psych. 9 1 7 5 8 6 2 4 10 3
D = (9-9)2 + (1-3)2 +...
Stats. 9 3 10 2 6 7 1 4 5 8
….+ (3-8)2 = 78
 = 1- [6D/n(n2-1)] = 0.53 not significantly correlated
PARALLELS with PARAMETRICS
NP/DF
• Randomization type, e.g.
runs test, 2, trend etc.
Sign Test

• Rank Tests (Medians)
Wilcoxon/Mann-Whitney,
Kruskal-Wallis, Rank
Correlation/(Regression)
• Normal Scores
• Kolmogorov-Smirnov
(EDF)
Parametric/Classical
• 2 test of proportions
• independent /matched
pairs t-test
• t-test both paired and
independent, ANOVA,
Correlation,Regression
• Normal - based
• Estimation/C.I. -general
NON-PARAMETRIC REFERENCES
•
•
•
•
Hollander M. “Nonparametric Statistical Methods”
Lehmann E.L. “Nonparametric Statistics based on Ranks”
Hajek J. “A course in Nonparametric Statistics”
Noether G.E. “Introduction to Statistics: A Nonparametric
Approach”
• Siegel S. “Nonparametric Statistics”
• Sprent P. “Applied Nonparametric Statistics”
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