CS 426 2011 Spring

5/3/2011 1 1

Presenter : Yubin Li

Professor : Dr. Bamshad Mobasher

Week 6: Descriptive Research

2

Outline

Introduction 1

aa2

DR design & Analysis 3

Discussions4

Descriptive Research

Introduction to Quantitative Research YouTube: introduction to Quantitative Research http://www.youtube.com/watch?v=GoQ9Zg8Fvf0Time

Quantitative Vs. Qualitative research

Table 1 : Comparison of features of Quantitative and Qualitative research

Quantitative Qualitative

Both are systematic in their approach

Objective Subjective

Deductive Inductive

Generalizable Not generalizable

Numbers Words 

Descriptive Research

4

Quantitative Research Methodologies: Descriptive Research Correlational Research Experimental Research Ex Post Facto Research Survey Research

Descriptive Vs. Experimental Vs. Ex post facto Descriptive (What is the current situation?) Experimental (What is the cause?) Ex post facto (What was the possible cause?)

5

Outline

Introduction 1

aa2

DR design & Analysis 3

Discussions4

Descriptive Research

6

Descriptive Research What is the Descriptive Research?

This type of research involves either identifying the characteristics of an observed phenomenon or exploring possible correlations among two or more. It primarily concerned with finding out “what is”, solving the problems through the interoperation of the data that has been gathered, (answering the questions who, what, where, when and how...)

Descriptive“ what is the current situation?” Numerical data gathered through tests, surveys, observations,

interviews variables are not manipulated but are measured as they occur Subgroups may be compared on some measure Two or more variables of a group may be correlated Doesn’t attempt to identify cause of differences or relationships,

just if they exist

7

Descriptive Research What the Descriptive Research can be used for?

Descriptive studies have an important role in social science research, such as business, government, public health, sociology and education research.

Can be applied to investigate questions such as: Do teachers hold favorable attitudes toward using computers in

schools? What kinds of activities that involve technology occur in sixth-

grade classrooms and how frequently do they occur? How have high school computing courses changed over the last

10 years? Is there a relationship between experience with multimedia

computers and problem-solving skills? What is the best way to provide access to computer equipment

in schools?

8

Outline

Introduction 1

aa2

DR design & Analysis 3

Discussions4

Descriptive Research

9

DR design & Analysis1. Descriptive Research Designs

Observation Studies Correlational Research Developmental Designs Survey Research

2. Using Checklists and Rating scales

3. Choosing a Sample in a Descriptive Study Sampling design Bias in Research sampling

4. Interpreting Data in Descriptive Research

10

DR design & Analysis1. Descriptive Research Designs – Observation Studies

In qualitative research: record in great detail In quantitative research: focus on a particular aspect of

behavior, and try to be as objective as possible Many strategies to maintain “objective”:

a) define behavior in a precise, concrete manner

b) divide the observation period into small segments…

c) use a rating scale to evaluate behavior

d) Have two/three people rate the same behavior Independently

e) Train the raters

Ultimately, an observational study can yield data that portray much of the richness and complexity of human behavior.

11

DR design & Analysis1. DR Design - Correlational Research

Examines the extent to which differences in one characteristic or variable are related to differences in one or more other characteristics or variables.

Did you realize that when children grow older, they are better reader? Age & reading ability -- correlation

12

DR design & Analysis1. DR Designs – Development Design

Cross-sectional study Vs. Longitudinal studies Cross-sectional study: people from different ages are sampled

and compared. Longitudinal study : a single group of people is followed over

the course of several months or years

13

DR design & Analysis1. DR Designs – Survey Research

Involves acquiring information about one or more groups of people-

Perhaps about their characteristics, opinions, attitudes, or previous

experiences, by asking them questions and tabulating their answers. Face-to-face and Telephone interviews Questionnaires

2. Checking List & Rating Scales Checking List : is a list of behaviors, characteristics, or other

entities that a researcher is investigating Rating scale: is more useful when a behavior, attitude, or other

phenomenon of interest needs to be evaluated.

14

DR design & Analysis3. Choosing a sample in a descriptive study

Sampling design

a) Probability sampling

Simple random sampling

Stratified random sampling

Proportional stratified sampling

Cluster sampling

Systematic sampling

b) Nonprobability sampling

Convenience sampling

Quota sampling

Purposive sampling

15

DR design & Analysis3. Choosing a sample in a descriptive study

Bias in Research sampling

Bias is any influence, condition, or set of conditions that singly or together distort the data

Bias can creep into a research project in a variety of subtle and undetected ways

Bias attacks the integrity of the facts, the research generalization may not be accurate.

16

DR design & Analysis4. Interpreting Data in Descriptive research

Two basic principle

a) seek the answer to a problem in the light of the data that related to the problem

b) collecting data and organizing data for extracting meaning of the data is all important.

Decide on a population

Choose sampling technique

Minimize entrance of bias

Develop a valid means

Collect, record, organize analyze

17

Outline

Introduction 1

aa2

DR design & Analysis 3

Discussions4

Descriptive Research

CS 426 2011 Spring

4/12/2011 18 18