Introduction to Educational Research (6th ed.)
Craig A. Mertler & C.M. Charles
Chapter 8
Analyzing Research Data and
Presenting Findings
This multimedia product and its contents are
protected under copyright law. The following
are prohibited by law:
• Any public performance or display,
including transmission of any image over a
network;
• Preparation of any derivative work,
including the extraction, in whole or in part,
1
Qualitative versus Quantitative Data
• Qualitative data
» Analyzed inductively—thought process using logic
to make sense of observations
» Goal is to uncover patterns, themes, categories, etc.
• Quantitative data
» Analyzed mathematically
» Goal is to describe data, show degree of relationship
or difference, & determine likelihood that sample
findings also exist in population
2
Copyright © Allyn & Bacon 2008
Analyzing Ethnographic Data
• Differs from the generic description of qualitative
analysis
» Research questions often emerge after data
collection (and even analysis) have begun; they are
not foreseen
» Conclusions are drawn from a broad view of human
behavior
• Analytical process is somewhat iterative and circular
»
»
»
»
Identify topics (through data collection)
Cluster topics into categories
Form categories into patterns
Draw explanations (conclusions) from patterns
• This on-going analytical process is known as logicoinductive or hypothetico-inductive analysis
• A very subjective process—bias is a strong possibility3
Copyright © Allyn & Bacon 2008
Analyzing Quantitative Data
• Key is the separation of the researcher from the
participants and the data—objectivity!
• Parameters—numerical indices that describe populations
• Statistics—numerical indices that describe samples
parameters
populations
statistics
samples
4
Copyright © Allyn & Bacon 2008
What Statistics Are Used For
• To summarize data in order to reveal what is typical and
atypical about a group
• To show relative standing of individuals in a group
• To show relationships among variables
• To show similarities and differences among groups
• To identify error inherent in sample selection
• To test for significance of findings
• To make inferences about a population
5
Descriptive Statistics
• Numerical indices and procedures that summarize and
simplify data about samples
• Measures of central tendency:
» Mean (M)
» Median (Mdn or Md)
» Mode (Mo)
• Measures of variability:
» Range (R)
» Variance (s2)
» Standard deviation (s or SD)
6
Copyright © Allyn & Bacon 2008
Descriptive Statistics (cont’d.)
• Measures of relative position:
» Percentile rank (%ile or PR)
» Stanine
» Converted scores (z-score, T-score, grade-equivalent,
etc.)
• Measures of relationship:
» Pearson correlation coefficient (r)
» Many other correlation coefficients
7
Copyright © Allyn & Bacon 2008
Inferential Statistics
• Numerical indices and procedures used to make
inferences about a population based on information
from a sample
» Error estimates
» Confidence intervals
» Tests of significance
◊ Significance of correlation
◊ Significance of differences between means (ttests, F-tests, etc.)
8
Copyright © Allyn & Bacon 2008
Cautions in Using Statistics
• Don’t try to do too much…!
» Stay within your skills and knowledge of statistics!
» Your research questions and/or hypotheses should
guide your analysis
• Statistical significance vs. practical significance
9
Copyright © Allyn & Bacon 2008
Presenting Your Findings
• Research findings are the information that results from
your analysis
• Findings from qualitative data analysis are usually
presented as summary statements and discussion
about the patterns which were observed
• Findings from quantitative data analysis are typically
presented in narrative form as well as visually (in
tables or graphs)
10
Copyright © Allyn & Bacon 2008
Applying Technology…
Web sites related to qualitative data analysis
•
AnSWR (www.cdc.gov/hiv/software/answr.htm)
•
EZ-Text (www.cdc.gov/hiv/software/ez-text.htm)
•
Qualrus (www.ideaworks.com/qualrus/index.html)
•
INTEXT (www.intext.de/eindex.html)
•
NUD*IST—N6
(www.qsrinternational.com/products/productoverview/product_overvi
ew.htm)
•
HyperRESEARCH (www.researchware.com)
11
Copyright © Allyn & Bacon 2008
Applying Technology…
Web sites related to quantitative data analysis
•
Dr. Trochim’s discussion of "Data Preparation"
(socialresearchmethods.net/kb/statprep.htm)
•
Dr. Trochim’s discussion of "Descriptive Statistics"
(socialresearchmethods.net/kb/statdesc.htm)
•
Dr. Trochim’s discussion of ”Inferential Statistics"
(socialresearchmethods.net/kb/statinf.htm)
•
Dr. Trochim’s discussion of "Correlation"
(socialresearchmethods.net/kb/statcorr.htm)
•
Dr. David W. Stockburger’s online statistics textbook
(business.clayton.edu/arjomand/book/sbk00.htm)
•
Dr. David W. Stockburger’s bibliography and statistics web resources
(business.clayton.edu/arjomand/book/biblio.htm)
•
StatCrunch online statistical analysis program
(www.statcrunch.com/)
•
Dr. Trochim’s interactive page for "Selecting Statistics"
(socialresearchmethods.net/selstat/ssstart.htm)
12
Copyright © Allyn & Bacon 2008