quantitative and qualitative data analysis lecture 1: introduction
DESCRIPTION
Quantitative and Qualitative Data Analysis Lecture 1: Introduction. Statistics (3rd Ed.) by David Freedman, Robert Pisani and Roger Purves . Norton Doing Data Analysis with SPSS Version 12 by Carver and Nesh . - PowerPoint PPT PresentationTRANSCRIPT
Dr. Engr. Sami ur Rahman
Quantitative and Qualitative Data AnalysisLecture 1: Introduction
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 2
Statistics (3rd Ed.) by David Freedman, Robert Pisani and Roger Purves. Norton
Doing Data Analysis with SPSS Version 12 by Carver and Nesh.
Qualitative Data Analysis: An Expanded Sourcebook, by Matthew B. Miles and A. Michael Huberman. 2nd Edition. Sage Publications: Thousand Oaks, CA
A Practical Guide to Scientific Data Analysis by David Livingstone ChemQuest, Sandown, Isle of Wight, UK
Reference books
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 3
Outline
Motivation
What is Data?
What is Data Analysis
Quantitative Data and Qualitative Data
Quantitative and Qualitative Data Analysis
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 4
Things aren’t always what we think!
Blind men and an elephant
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 5
Data
Student No Hours Studied Marks1 1 402 4 803 2 504 4 705 5 906 3 607 2 458 1 429 4 8510 3 70
What information do we get from this data??
Data: Values of qualitative or quantitative variables.
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 6
Data Analysis
Student No
Hours Studied Marks
1 1 402 4 803 2 504 4 705 5 906 3 607 2 458 1 429 4 8510 3 70
Student No
Hours Studied Marks
1 1 408 1 423 2 507 2 456 3 6010 3 702 4 804 4 709 4 855 5 90
Sorted data
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 7
Data Presentation
Student No
Hours Studied Marks
1 1 408 1 423 2 507 2 456 3 6010 3 702 4 804 4 709 4 855 5 90 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
0
10
20
30
40
50
60
70
80
90
100
4042
50
45
60
70
80
70
85
90
Series1Ma
rks
Hours studied
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 8
What is data analysis?
Data analysis is the process of turning data into information
An attempt by the researcher to summarize collected data
Data Interpretation is an attempt to find meaning
Good analysis communicates something meaningful about the world
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 9
Quantitative Data:
Data that is numerical, counted, or compared on a scale
Qualitative Data:
Textual data
Interview transcripts
Case notes/ clinical notes
Photographs
Video recordings
Types of Data
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 10
Quantitative Data Analysis:
Converting quantitative data into information
Qualitative Data Analysis:
Converting qualitative data into information
Types of Data Analysis
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 11
Quantitative Analysis
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 12
Quantification of Data
Quantification Analysis :
The numerical representation and manipulation of observations for the purpose of describing and explaining the phenomena that those observations reflect.
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 13
Quantitative Analysis
Can be used to answer questions like
What is the percent distribution?
How much variability is there in the data?
Are the results statistically significant?
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 14
Simple Quantitative Analysis
Averages
Mean: add up values and divide by number of data points
Median: middle value of data when ranked
Mode: figure that appears most often in the data
Percentages
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 15
Central Tendency
Central tendency: The way in which quantitative data tend to cluster around some value. A measure of central tendency is any of a number of ways of specifying this "central value"
Median Mode
Central Tendency
Average (Mean)
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 16
Mean
Mean (arithmetic mean) of data values
1 1 2
n
ii n
XX X X
Xn n
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 17
Mean
The most common measure of central tendency Affected by extreme values (outliers)
0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 12 14
Mean = 5Mean = 6
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 18
Median
Median: The “middle” numberNot affected by extreme values
0 1 2 3 4 5 6 7 8 9 10
Median = 5
0 1 2 3 4 5 6 7 8 9 10 12 14
Median = 5
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 19
Mode
Mode: Value that occurs most often Not affected by extreme values There may be no mode There may be several modes
Mode = 9
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 0 1 2 3 4 5 6
No Mode
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 20
Simple quantitative analysis
Graphical representations give overview of data
Number of errors made
0
2
4
6
8
10
0 5 10 15 20
User
Nu
mb
er o
f er
rors
mad
e
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 21
Simple quantitative analysis
Graphical representations give overview of data
Internet use
< once a day
once a day
once a week
2 or 3 times a week
once a month
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 22
Strengths of Quantitative Research
Precise, quantitative, numerical data
Testing hypothesis/confirming theories
Generalizing finding, random samples with sufficient size
Comparatively quick data collection
Less time consuming analysis
May minimize personal bias
.
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 23
Weaknesses of Quantitative ResearchOnly applicable for measurable (quantifiable) phenomena
Simplifies and ”compresses” the complex reality, lack of detailed narrative
Theories or categories might not reflect local constituencies’ understandings
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 24
Qualitative Analysis
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 25
Qualitative Data
Narratives, logs, experience
Interviews
Diaries and journals
Notes from observations
Photographs
Video recordings
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 26
What is Qualitative Research?
Research studies that investigate the quality of
Relationships
Activities
Situations
Materials
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 27
Qualitative Data Analysis
Used for any non-numerical data collected as part of the evaluation
Unstructured observations
Analysis of written documents
Diaries, observations
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 28
Qualitative Data Analysis
Answers questions like:
Is the project being implemented according to plan?
What are some of the difficulties faced by staff?
Why did some participants drop out early?
What is the experience like for participants?
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 29
Steps in Qualitative Research
The steps are as follows (in some cases):
Identification of the phenomenon and hypothesis generation
Identification of the participants in the study
Data collection (continual observance)
Data analysis
Interpretation/Conclusions
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 30
Generalization in Qualitative Research
A generalization is usually thought of as a statement or claim that applies to more than one individual, group, or situation.
The value of a generalization is that it allows us to have expectations about the future.
A limitation of Qualitative Research is that there is seldom justification for generalizing the findings of a particular study.
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 31
Trustworthiness in Qualitative ResearchCheck on the trustworthiness of the researchers:Compare one informant’s description with another informant’s
description of the same thing.Triangulation: Comparing different information on the same
topic. Data triangulation Use of multiple data sources
Students, teachers, administrators, etc. Methods triangulation Interviews, observations, etc.
Researcher triangulation Use a team of researchers.
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 32
Criteria for judging research
Quantitative Internal validityDid A cause B?
External ValidityAre these findings generalizable?
ReliabilityAre the measures repeatable?
ObjectivityAre the findings free of researcher bias/values?
QualitativeCredibilityBelievable from participant’s view
TransferabilityCan this finding be transferred to other contexts?
DependabilityWould another researcher come to similar conclusions?
University Of Malakand | Department of Computer Science | UoMIPS | Dr. Engr. Sami ur Rahman | 33
Thanks for your attention