Lecture Slides - DePaul University

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Notes on Research Proposals
Components of the Research Proposal
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Problem Description/Statement
Research Objectives
Importance/Benefits of the Study
Literature Review
Research Design / Data Analysis
Deliverables
Schedule
[Facilities and Special Resources]
References
Budget (Appendix)
Problem Statement
• Review the discussion from Week 2 on
problem statements.
Purpose of the Problem Statement
• Represents the reasons/motivation behind your proposal
(based on the specific domain of study).
• It specifies the conditions you want to change or the gaps
in existing knowledge you intend to fill (this is the
specification of the research problem).
• Should be supported by evidence.
• Specifies your hypothesis that suggests a solution to the
problem.
• Shows your familiarity with prior research on the topic and
why it needs to be extended.
• Even if the problem is obvious, your reviewers want to
know how clearly you can state it.
Guidelines for writing a good
abstract/problem statement
All should have the following elements in this order:
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4.
State the general case / problem
Describe what others have done
What’s missing / where is the gap in knowledge?
Describe the proposed solution or research
objectives/questions
5. Specify one or more specific hypotheses
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Should include specific metrics/measurements
Discuss how their validation addresses the research questions
6. Specific results (or research design, if it is a proposal)
Purpose of the Research
Objectives Section
• Specify the outcome of your project, the
end product(s)
• Keep you objectives
– Specific: indicate precisely what you intend to
change through your project
– Measurable –what you accept as proof of
project success
– Logical – how each objective contributes to
systematically to achieving your overall goal
Research Objectives
• Flows naturally from the problem statement
– state your hypotheses clearly
– give the reader a concrete, achievable goal
• Verify the consistency of the proposal
– check to see that each objective is discussed in
the research design, data analysis and results
sections
Literature Review
• Recent or historically significant research
studies
• Always refer to the original source
• Discuss how the literature applies, show the
weaknesses in the design, discuss how you
would avoid similar problems
• How is your idea different/better?
Importance/Benefits of the Study
• Importance of the doing the study now
• What are the potential impacts on
– Research in the area
– Applications of the research if successful
– Broader impact (in other areas, on the society,
in education, etc.)
• If you find this difficult to write, then most
likely you have not understood the problem
Research Design
• What you are going to do in technical terms.
– May contain many subsections
– Be specific about what research methodology you
will use and why
– Provide details of your proposed solutions to the
problem and sub-problems
– Provide information for tasks such as sample
selection, data collection, instrumentation,
validation, procedures, ethical requirements
Schedule & Deliverables
• Include the major phases of the project
• exploratory studies, data analysis, report generation
• Critical Path Method (CPM) of scheduling may help
• Deliverables:
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Measurement instruments
Algorithms
Computer programs / prototypes
Comparative evaluation
Other technical reports
Budget and Resources
• Itemized Budget
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Access to special systems or computers
Infrastructure needs
Costs of surveys, user studies, etc.
Cost of travel if related to research design
• Provide a Budget Narrative
• This part is usually an appendix.
Proposal Characteristics
• Straightforward document
– No extraneous or irreverent material
• Don’t tell us why you became interested in the topic
– The first words you write are the most important ones
• Not a literary production
– Clear, sharp and precise
– economy of words; no rambling sentences
• Clearly organized
– Outlined with proper use of headings and subheadings
Suggested Organization
• Title, Abstract, Keywords (problem statement)
• Introduction and Overview
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Background information; problem description in context
Hypotheses and objectives
Assumptions and delimitations
Importance and benefits
Related Work/Literature Review
Research Design and Methodology
Plan of Work and Outcomes (deliverables, schedule)
Conclusions and Future Work
References
Budget (appendix)
Weaknesses in Research Proposals
• Research Problem
–unfocused
–unimportant (done before!)
–more complex
–limited relevance
Weaknesses in Research Proposals
• Research Design
– so vague it prevents evaluation
– inappropriate or impossible data
– procedures inappropriate for problem
• Threats to validity
• Lack of reliable measures
– lacking controls
A Sample Research Proposal
• Read (and study) the sample proposal in
Chapter 5 of in Practical Research
• Fill in the critique in Chapter 12 for this
proposal.
– Since the critique is designed for a REPORT,
simply change the tense for most questions.
• Is the sample size adequate? -> Will the sample size be
adequate
Guide to Writing the Research
Proposal
5 Key Questions to Answer in
Your Problem Statement
• Does your problem statement:
– Demonstrate a precise understanding of the problem
you are attempting to solve?
– Clearly convey the focus of your project early in the
narrative?
– Indicate the relationship of your project to a larger set
of problems and justify why your particular focus has
been chosen?
– Demonstrate that your problem is feasible to solve?
– Make others what to read it further?
5 Key Questions to Answer for
Purpose and Objectives
• Does this section
– Clearly describe your project’s objective, hypotheses
and/or research question?
– Bury them in a morass of narrative?
– Demonstrate that your objectives are important,
significant and timely?
– Include objectives that comprehensively describe the
intended outcomes of the project?
– State objectives, hypothesis or questions in a way they
can be evaluated or tested later
Writing Tips for Objectives
Section
• Don’t confuse your objectives (ends) with
you methods (means).
• A good objective emphasizes what will be
done, whereas a method will explain why or
how it will be done.
• Include goals (ultimate) and objectives
(immediate)
Purpose of the Research Design
• Describes your project activities in detail
• Indicates how your objective will be
accomplished
• Description should include the sequence,
flow, and interrelationship of activities
• It should discuss the risks of your method,
and indicate why your success is probable
• Relate what is unique about your approach.
Data Analysis
Data Analysis is essentially a four step process
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Identify precisely what will be evaluated. If you wrote
measurable objectives, you already know.
Determine the methods used to evaluate each objective.
More precisely, you will need to describe the information
you will need and how you propose to collect it.
Specify the analyses you plan to make and the data you need
to collect. Your design may be simply to observe behavior
of a particular population or something more complex like a
rigorous experimental and multiple control group design.
Summarize the resulting data analyses and indicate its use.
Consider mock data tables that show what your resulting data
might look like.
Key Questions to Answer for
Research Design/Data Analysis
• Does the research design and data analysis section
– Describe why analysis is needed in the project?
– Clearly identify the purpose of your analysis?
– Demonstrate that an appropriate analysis procedure is
included for each project objective
– Provide a general organizational plan or model?
– Demonstrate what information will be needed to
complete the analysis, the potential sources and the
instruments that will be used to collect it.
Writing Tips for Research Design
• Begin with your objectives
• Describe the precise steps you will follow to carry
out each objective, including what will be done,
and who will do it.
• Keep asking and answering the “What’s next?”
question.
• Once you have determined the sequence of events,
cast the major milestones into a time-and-task
chart
Scientific Writing
• Prosaic
• Clear, accurate, but not dull
• Economy – every sentence necessary but
not to the point of over condensing
• Ego less – you are writing for the readers
not yourself
Scientific Tone
• Objective and accurate
• To inform not entertain
• Do not over qualify – modify every claim
with caveats and cautions
• Never use idioms like “crop up”, “loose
track”, “it turned out that”, etc.
• Use examples if they aid in clarification
Scientific Motivation
• Brief summaries at the beginning and end of
each section
• The connection between one paragraph and
the next should be obvious
• Make sure your reader has sufficient
knowledge to understand what follows
Other Writing Issues
• The upper hand – inclusion of offhanded remarks
like “ …this is a straightforward application …”
• Obfuscation – aim is to give an impression of
having done something without actually claiming
to have done it
• Analogies – only worthwhile if it significantly
reduces the work of understanding, most of the
time bad analogies lead the reader astray
Writing Issues
• Straw men – indefensible hypothesis posed
for the sole purpose of being demolished
– “it can be argued that databases do not require
indexes”
• Also use to contrast a new idea with some
impossibly bad alternative, to put the new
idea in a favorable light
Unsubstantiated Claims
• Example:
– Most user prefer the graphical style of interface.
– We believe that ….
• Example
– Another possibility would be a disk-based
method, but this approach is unlikely to be
successful.
– Another …, but our experience suggests that …
References and Citation
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Up-to-date
Relevant (no padding)
Original source
First order: books and journal articles
Second order: conference article
Third order: technical report
No private communications or forums ( material
cannot be accessed or verified) if you must leave
as a footnote not in the bibliography
• Do not cite support for common knowledge
Reference and Citation
• Carefully relate your new work to existing
work, show how your work builds on
previous knowledge, and how it differs
from other relevant results.
• References – demonstrate the claims of
new, knowledge of the research area,
pointers to background reading
Citation Style
• References should not be anonymous
– Other work [6] -> Marsden [6] has …
• In self-references, readers should know that
you are using yourself to support your
argument not independent authorities
• Avoid unnecessary discussion of references,
Several authors …., we cite …
Citation style
• Ordinal-number style, name-and-date style,
superscripted ordinal numbers, and strings.
• Use anyone, but use one!
• Entries ordered
– By appearance of citation
– alphabetically
Quotation
Text from another source
If short – enclosed in double quotes
If long – set aside in an indented block
Long quotations, full material, algorithms,
figures may require permission from the
publisher and from the author of the original
Use of quotes for other reasons is not
recommended
Acknowledgements
• Anyone who made a contribution
• Advice, proofreading, technical support,
funding resources
• Don’t list your family, unless they really
contributed to the scientific contents
Ethics
• Don’t
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Present opinions as fact
Distort truths
Plagiarize
Imply that previously published results are original
Papers available on the internet – authors put out an
informal publication and becomes accepted as a formal.
It is expected that the informal version will be removed
Notes on Research Design
• You have decided
– What the problem is
– What the study goals are
– Why it is important for you to do the study
• Now you will construct the research design
which describes what you are going to do in
technical terms.
General Structure of Research Proposals
Research Design
• Is a plan for selecting the sources and types
of information used to answer the research
question.
• Is a framework for specifying the
relationships among the study’s variables
• Is a blueprint that outlines each procedure
from the hypothesis to the analysis of data.
Research Design
The research design will provide information for
tasks such as
• Sample selection and size
• Data collection method
• Instrumentation
• Procedures
• Ethical requirements
• Rejected alternative designs
Classification of Research
Designs
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Exploratory or formal
Observational or communication based
Experimental or ex post facto
Descriptive or causal
Cross-sectional or longitudinal
Case or statistical study
Field, laboratory or simulation
Exploratory or Formal
• Exploratory studies tend toward loose structures
with the objective of discovering future research
tasks
– Goal - to develop hypotheses or questions for further
research
• Formal study begins where the exploration leaves
off and begins with the hypothesis or research
question
– Goal – test the hypothesis or answer the research
question posed
Observational or Communication
Based
• Observational studies – the researcher
inspects the activities of a subject or the
nature of some material without attempting
elicit responses from anyone.
• Communicational – the researcher questions
the subjects and collects response by
personal or impersonal means.
Experimental or Ex Post Facto
• In an experiment the researcher attempts to control
and/or manipulate the variables in the study.
Experimentation provides the most powerful
support possible for a hypothesis of causation
• With an ex post facto design, investigators have
no control over the variables in the sense of being
able to manipulate them. Report only what has
happened or what is happening. Important that
researches do not influence variables
Descriptive or Causal
• If the research is concerned with finding out
who, what, where, when or how much then
the study is descriptive.
• If is concerned with finding out why then it
is causal. How one variable produces
changes in another.
Cross-sectional or Longitudinal
• Cross-sectional are carried out once and
represent a snapshot of one point in time.
• Longitudinal are repeated over an extended
period
Case or Statistical Study
• Statistical studies are designed for breath rather
than depth. They attempt to capture a
population’s characteristics by making inference
from a sample’s characteristics.
• Case studies – full contextual analysis of fewer
events or conditions and their interrelations.
(Remember that a universal can be falsified by a
single counter-instance)
Field, Laboratory or Simulation
• Designs differ in the actual environmental
conditions
Quantitative v. Qualitative
Approaches
• Categorize research studies into two broad
categories
• Quantitative – relationships among measured
variable for the purpose of explaining, predicting
and controlling phenomena
• Qualitative – answer question about the complex
nature of phenomena with the purpose of
describing and understanding from the
participant’s point of view
The Validity of Your Method
• Accuracy, meaningfulness, an credibility
• Most important questions:
– Does the study have sufficient controls to
ensure that the conclusions we draw are truly
warranted by the data? (internal validity)
– Can we use what we have observed in the
research situation to make generalizations about
the world beyond that specific situation?
(external validity)
Strategies to reduce internal
validity problems
• Controlled laboratory study
• A double-blind experiment
• Unobtrusive measures ( to see where people
use the library look at worn flooring)
• Triangulation – multiple sources
Strategies to enhance external
validity
• A real-life setting – artificial settings may
be quite dissimilar from real-life
circumstances
• Representative sample
• Replication in a different context
Formal Notion of Validity
“The best available approximation to the truth of a
given proposition, inference, or conclusion”
Source: Research Methods Knowledgebase
Types of Validity
• Conclusion Validity:
– Is there a relationship between the two variables?
• Internal Validity:
– Assuming that there is a relationship, is it a causal one?
• Construct Validity:
– Assuming that there is a causal relationship, can we claim that
the program reflected our construct of the program and that our
measure reflected well our idea of the construct of the measure?
• External Validity:
– Can we generalize the (causal) effect to other settings, domains,
persons, places or times?
Types of Validity
Source: Research Methods Knowledgebase
Setting of the Problem
Statement of
the Problem
Establishes
Goal
Additional information to comprehend
fully the meaning of the problem
hypothesis
scope
definitions
assumptions
Hypotheses
• Tentative proposition
• formulated for empirical testing
• Means for guiding and directing
– kinds of data to be collected
– analysis and interpretation
• have nothing to do with proof
• acceptance or rejection is dependant on
“data”
Examples of Hypotheses
• Error-based pruning reduces the size of decision trees (as
measured in the number of nodes) without decreasing accuracy
(as measured by error rate)
• The use of relevance feedback in an information retrieval
system, results in more effective information discovery by
users (as measured in terms of time to task completion)
• The proposed approach for generating item recommendations
based on association rule discovery on purchase histories results
in more accurate predictions of future purchases when
compared to the baseline approach.
• [From a recent Google experiment] Longer documents tend to
be ranked more accurately than shorter documents because their
topics can be estimated with lower variance.
Rejecting the Hypothesis
• Often researchers set out to disprove an
opposite/competing hypothesis
• Example: We believe that test strategy A
uncovers more faults than test strategy B.
So our hypothesis will be that
– Programmers using test strategy A will uncover
more faults than programmers using test
strategy B for the same program.
Rejecting the Hypothesis
• However, we cannot actually prove this
hypothesis, we instead will try to disprove
an opposite hypothesis
– There will be no difference in the fault
detection rate of programmers using test
strategy A and those using test strategy B for
the same program.
Types of Hypotheses
• Existential
– An entity or phenomenon exists (perhaps with a specified
frequency)
– “Atoms contain uncharged subatomic particles (neutrons)”
• Compositional
– An entity or phenomenon consists of a number of related
parts or components (perhaps with a specified frequency)
– “Atoms consist of proton, electrons, and neutrons.”
– “All decision tree algorithms can be divided into a growing
phase and a pruning phase.”
Types of Hypotheses
• Correlational
– Two measurable quantities have a specified association
– “An element’s atomic weight and its properties are
correlated.”
– “The size of a decision tree constructed using error-based
pruning grows linearly with the size of training set.”
• Casual
– A given behavior has a specified causal mechanism
– “The low reactivity of noble gases is caused by their full
outer shell of valence electrons.”
– “The use of relevance feedback results in more effective
information discovery by users”
Rejecting the Hypothesis
• If there is a significant difference in the
fault detection rate we can reject the “no
difference” and by default, support our
research hypothesis
• the “no difference” = null hypothesis
Recall: Falsifiability
• Falsifiability is the logical possibility that an assertion
can be shown to be false by evidence
• Does not mean “false.” Instead, if a falsifiable
proposition is false, its falsehood can be shown by
experimentation, proof, or simulation.
• There are different degrees of falsifiability
• What make a hypothesis unfalsifiable?
– Vagueness – theory does not predict any particular experimental
outcome
– Complexity/Generality – theory “explains” any experimental result
– Special pleading – traditional experimental methods are claimed not
to apply
Delimiting the Research
• This is what the researcher does not want to
do in the project
– Should be stated clearly and explicitly.
• What will be done is part of the problem
statement.
Experiments
• Studies involving the intervention by the
researcher beyond that required for
measurement
• usually, manipulate some variable in a
setting and observe how it affects the
subject (cause and effect)
• there is at least one independent variable
and one dependent variable
Independent Variable
• Variable the researcher manipulates
• For our hypothesis concerning test strategies, we
may take a sample of software engineers and
randomly assign each to one of two groups: one
using test strategy A and the other test strategy B.
Later we compare the fault detection rate in the
two groups.
– We are manipulating the test strategy, thus it is the
independent variable
Dependent Variable
• Variable that is potentially influenced by
the independent variable
• in our last example, the dependent variable
is fault detection rate
• Presumably the fault detection rate is
influenced by test strategy applied
• there can be more than one dependent
variable
Conducting an Experiment
• Seven activities
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select relevant variables
specify the level(s) of treatment
control the experimental environment
choose the experimental design
select and assign the subjects
pilot-test, revise, and test
analyze the data
Select the Relevant Variables
• Translate our problem into the hypothesis that best
states the objectives of the research
• how concepts are transformed into variables to
make them measurable and subject to testing
• research question:
– Does a product presentation that describes product
benefits in the introduction lead to improved retention
of the product knowledge?
The Speculation
• Product presentations in which the benefits
module is placed in the introduction of a 12
minute message produce better retention of
product knowledge that those where the
benefits module is placed in the conclusion.
Researcher’s Challenge
• Select variables that are the best operational
representations of the original concepts.
– Sales presentation, product benefits retention,
product knowledge
• Determine how many variables to test
– constrained by budget, the time allocated, the
availability of appropriate controls, and the
number of subjects
Researcher’s Challenge
• Select or design appropriate
measures/metrics for them
– thorough review of the available literature and
instruments.
– Adapted to unique needs of the research
situation
Choosing an Experimental
Design
• Experimental designs are unique to the
experimental method
• statistical plans to designate relationships between
experimental treatments and the experimenter’s
observations
• improve the probability that the observed change
in the dependent variable was caused by the
manipulation of the independent variable
Validity in Measurements
• Validity: the extend to which instrument
measures what is supposed to be measured
– E.g., thermometer  temperature
– E.g., IQ Test  Intelligence?
– E.g., CPU time  algorithm complexity or
efficiency
Reliability of Measurement
• Reliability: accuracy and consistency by
which the instrument can perform
measurement
– Accuracy exists only if there is consistency (not
necessarily the other way around)
– Need to measure more than once
– Reliability is a necessary but not sufficient
condition for validity
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