Statistics
Lecture by S.Imran
What is research?
To study a
phenomenon/problem/issue
comprehensively to find its
solution.
For example
Fear
Dengue
Terrorism
What is Science?
Who are the Scientists?
People with white-coat working in
laboratories, doing different kinds of
experiments?
Cut-off from the society?
Always discovering or inventing new
things like atom bomb, germs, virus, etc.
This notion is completely wrong
What is Science?
People who study phenomenon/
problem/issue systematically to
find its solution are called scientists
So science is basically a systematic
inquiry of
problems/issues/phenomenon
Scientific Research?
Systematic, controlled, empirical and
critical investigation of phenomenon
guided by some theory or
hypothesis.
Book to consult: Mass Media
Research: An Introduction by Wimmer and
Dominick
Aim of Scientific Research
Is scientific research (systematic inquiry
of problem) aimed for the betterment of
the society or else?
Answer is: A big NO
Than why a scientific research is
conducted?
Aim of Scientific Research?
The aim of Scientific research is
theory
Theory
Generati
on
Verificati
on
What is Theory?
Theory is a logic
What is logic?
Relationship between two or more
things/ideas /concepts
For example
Hard working ------------ Academic Grades
Food --------- Health
Gun -------- Fear
Theory
Scientifically this relationship is
called proposition.
A Theory can comprise a single or
set of propositions
Theory
So a scientific research is basically
aimed to
EITHER
generate such relationships among
different concepts/constructs
OR
verify such relationships among different
concepts
On the basis of this
We can categorize a scientific
research into two categories
1. Theory Generation approach
(Inductive or Qualitative )
2. Theory Verification approach
(Deductive or Quantitative)
Steps of Scientific Research
1. Selection of Problem/issue
2. Study Previous research about the
selected topic and Logic/theory
( Called Literature Review)
3. Formulation of Hypotheses/
Research Question
Hypotheses for Quantitative Research
Research Question for Qualitative Research
Steps of Scientific Research
4.
5.
6.
7.
Selection of Research Methodology
Data Collection
Data Analysis & Findings
Conclusion
Theory verified or not?
what new theory created?
Point to Remember
Applying Statistics is part of
quantitative Research
What is statistics?
Statistics is the science of conducting
studies to
collect,
organize,
summarize,
analyze, and
draw conclusions
from data.
In simple words
Statistics is to
Collect data
Describe data
Draw inferences from data
Descriptive
Inferential
What is data?
Anything (names or numerals) we collect is
data
if names than string data
If numerals than numeric data
From Whom?
Population
Sampling Frame
Sample
Sampling Techniques
Probability Technique
Non-probability Techniques
Nature of data
Levels of data / measurement
Nominal
(attributes)
Ordinal
Interval
(numbers)
Ratio
Qualitative data
Quantitative data
1. Data Collection
From Whom?
Population
Sampling Frame
Sample
Sampling Techniques
Probability Technique
Non-probability Techniques
How?
By using some tool/ Instrument
In Media studies tools can be
Questionnaire
Interview Schedule
Code sheets
Surveys
Content analysis
Tools
Tools comprises of Variables,
What is a variable?
A characteristics that can vary among individuals
Uni-dimensional
Can be directly observed/measured e.g age,
gender, class,
Multi-dimensional
They cannot be measured directly e.g
achievement, intelligence, participation,
involvement
Multi-dimensional
concepts and construct
Concepts
Abstract idea about some thing, formed by generalization.
e.g.
Construct
,abstraction with some added meanings
e.g.
If they cannot be measured directly, than how we measure
them?
The answer is through scales
What are scales?
Kinds
IV
DV
Moderating
Mediating
Confounding/Extraneous
How to measure variables?
Direct measurement (For unidimensional)
Indirect Measurement (For multidimensional)
By using scales or indexes
What is a scale?
Scales used in Media studies
Likert Scale
Semantic differential Scale
Flow Chart
Description
(Descriptive Statistics)
Descriptive statistics consists of the
collection, organization,
summarization, and presentation of
data.
Descriptive Statistics
Types of descriptive statistics:
Organize Data
Tables
Frequency Distributions
Percentages
Graphs
Bar Chart or Histogram
Frequency Polygon
Frequency Curve
Pi chart
Descriptive Statistics
Data Distribution Summary Statistics
Tables Graphs
Measure of
Measure of
1.Frequency 1. Bar Chart/Histogram
Central Tendency
Dispersion
2. Percentage
2. Pi Chart
1. Mean
1.
Range
3. Frequency Polygon
2. Mode
2. Variance
4. Frequency Curve
3. Median
3.
Standard
Deviation
Normal
Non-Normal
outliers
Skewness
Kurtosis
Tables
No. of hour People Watch TV in a day
3, 5, 3, 2, 7, 4, 3, 5, 1, 6,
Hours
Frequency (f)
Percentage
(%)
10%
10%
30%
10%
20%
10%
10%
Graphs
Bar Chart/Histogram
Polygon
Pi chart
Measure of Central
Tendency
What is the center of data?
Mean
Mathematical Average
average
Sum of all value
physically middle
no. of values
Mode
Median
Most occurring value
Sensitive to outlier
outlier
Data is interval or ratio
interval or ordinal
Position
value with highest frequency
does not affect with
nominal
Data Distribution
Symmetric Cure
Properties of mean and
median
For symmetric distributions, mean = median
For skewed distributions, mean is drawn in
direction of longer tail, relative to median
Mean valid for interval scales, median for
interval or ordinal scales
Mean sensitive to outliers (median often
preferred for highly skewed distributions)
When distribution symmetric or mildly
skewed or discrete with few values, mean
preferred because uses numerical values of
observations
3. Draw Inferences
(Inferential Statistics)
Inferential statistics consists of
generalizing from samples to
populations, performing estimations
and hypothesis tests, determining
relationships among variables, and
making predictions.
Hypothesis
What is a Hypothesis?
Kinds of hypothesis
Null
Alternative
Dimensions of Hypothesis
Directional (one tailed)
Non-directional (2 tailed)
What is Probability Level
(p)?
