Deduction vs. Induction
Deduction vs. Induction
Deduction vs. Induction
Induction
commonly associated
with formal logic.
involves reasoning
from known premises,
or premises presumed
to be true, to a certain
conclusion.
the conclusions
reached are certain,
predictable,
inescapable.
commonly known as
informal logic, or
everyday argument
involves drawing
uncertain inferences,
based on probabalistic
reasoning.
the conclusions
reached are probable,
reasonable, possible,
believable.
Example of
Induction
Boss to employee:
Biff has a tattoo of an
anchor on his arm. He
probably served in the
Navy.
vegetarian animals
tortoises
Thus, Bessie
must be a
vegetarian
All tortoises
fall in the
circle of
animals that
are
vegetarians
Bessie
Other types of
deductive arguments
Suppose every place in
the world that people
live is represented by
the blue space inside
the rectangle. Suppose
the long pink oval
represents all the
wooden houses in the
world. And, suppose
the green circle
represents Canada.
The most logical
conclusion one can
draw from the figure is:
Deductive
reasoning is either
valid or invalid.
If the reasoning
employed in an
argument is valid and
the arguments
premises are true,
then the argument is
said to be sound.
valid reasoning +
true premises =
sound argument
Inductive reasoning
enjoys a wide range of
probability; it can be
possible, reasonable,
credible, etc.
the inferences drawn
may be placed on a
continuum ranging from
sound at one end to
fallacious at the other.
fallacious
sound
Deductive Reasoning
Law of Detachment
The law of detachment
(also known as affirming
the antecedent) is the
first form of deductive
reasoning.
PQ (conditional
statement)
P (hypothesis stated)
Q (conclusion deduced)
Law of Syllogism
The law of syllogism takes
two conditional statements
and forms a conclusion by
combining the hypothesis
of one statement with the
conclusion of another
PQ
QR
Therefore, PR.
The following is an example:
not sound:
Everyone who eats steak is a
quarterback.
Inductive Reasoning
Inductive
reasoning, also
known as
induction, is a kind
of reasoning that
constructs or
evaluates general
proposition that
are derived from
specific examples.
Examples
7. Administer research
instruments / collect data
8. Process data
9. Analysis and interpretations
10. Findings / Conclusions
11. Write up findings
/conclusions
Important Topics
Data Collection
Methods
Interviews
Types of Interviews
Questionnaire, types
Theory
Theory is a
standardized
principle on
which basis we
can explain the
relationship
between two or
more concepts
or variables
PURPOSE OF THEORY
Prediction and
understanding are the
two purpose of theory.
LEVELS OF THEORY
1. Abstract level
At the abstract level.
Concepts and
propositions are the
elements of theory
2. Empirical level
At the empirical level
theory is concerned with
variables and testable
hypothesis, the empirical
counterparts of concepts
and propositions.
Motivation,
thirst, honesty,
satisfaction
Hypothesi
s
concept
variable
Abstract
level
Empirical
level
Temperature &
Productivity
Height & Weight,
Distance & Speed
Height, Weight,
Temperature,
Distance
Theory Development
Theory
All rosebushes have thorns
Deduction
Predicted Observation
Induction
Actual Observation
3. Data Collection
4. Findings
5. Hypothesis confirmed or
rejected
6. Revision of theory
Induction
Deductio
n
2. Hypothesis
2. Data Collection
3. Findings
4. Generation of Theory
Research Paradigms
Positivism
Determination
Reductionism
Empirical
observation and
measurement
Theory
verification
Interpretivism
Pragmatism
Understanding
Multiple
participant
meanings
Social and
historical
construction
Theory generation
Consequences
of actions
Problem
centered
Real-world
practice
oriented
Sr.
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Philosophical Assumptions
Philosophical
Assumption
Ontology: -
Positivism
Interpretivism
Pragmatism
Multiple realities
shaped by
researchers prior
understanding
(constructionism).
e.g. researchers
provides quotes to
illustrate different
perspectives.
Closeness (e.g.
researchers visit
participants at their
sites to collect data)
It is cased on the
perceptions of the
individuals about the
world. (Subjective)
Practicality (e.g.
researchers collect
data by what work to
address research
question).
Objective + Subjective
Biased (e.g.
researchers actively
talk about their biases
and interpretations)
Formal or informal
(e.g. researchers may
employ both formal
and informal styles of
writing).
Inductive (e.g.
researchers start with
participants views and
build up to patterns,
theories and
generalizations)
Combining (e.g.
researchers collect
both Quantitative an
Qualitative data and
mix them )
Strategies of Inquiry
Grounded theory,
ethnography, case
study and narratives
Sequential, concurrent
and transformative.
Methods
Open ended
questions, emerging
approaches, and text
and image analysis.
(Qualitative)