Quantitative research present

By :

Ahmad Adnan bin Mohd Shukri

Introduction

– QD is based in the scientific method.

– Uses deductive reasoning.

– Researcher forms hypothesis, collects data in an

investigation of the problem.

– Then, uses the data from the investigation, after analysis is

made and conclusions are shared, to prove the hypotheses

are true or false.

4 Types of Quantitative Design

1. Experimental studies

2. Comparative

3. Correlational

4. Survey

Experimental Studies

– Often called true experimentation.

– Use the scientific method to establish cause-effect

relationship among variables in a research study.

– Researchers make an effort to control for all variables except

the one being manipulated (independent variable).

– The effects of the independent variable on the dependent

variable are collected and analysed for a relationship.

– Although questions may be posed in the other forms of

research, experimental research is guided specifically by a

hypothesis.

– Sometimes experimental research can have several

hypotheses.

– A hypothesis is a statement to be proven or disproved.

– Once that statement is made, experiment is begun

The major feature that distinguishes

experimental research from other types of

research is ….

–the researcher manipulates

the independent variable.

–Subjects are randomly

assigned to experimental

treatments

Experimental designs should be

developed to ensure internal and

external validity of the study

Internal Validity

– Are the results of the study (DV) caused by the factors

included in the study (IV) or are they caused by other factors

extraneous variables (EV) which were not part of the study.

– EV are unwanted variables that may have an effect on the

experimental outcome. (ex: if you ware worried about

gender, only include one gender in the study).

Threats to Internal Validity

– Subject characteristics ( Selection Bias)

– The groups may have been different from the start. If you

were testing instructional strategies to improve reading and

one group enjoyed reading more than the other group, they

may improve more in their reading because they enjoy it,

rather than the instructional strategy you used.

– Location

– Perhaps one group was at a disadvantage because of their

location.

– Example, the city may have been demolishing a building next

to one of the school in your study, there are constant

distractions which interfere with your treatment.

– Instrumentation (Instrument Decay)

– The testing instruments may not be scored similarly. Perhaps

the person grading the post test is fatigued and pays less

attention to the last set of papers reviewed. It may be that

those papers are from one of your groups and will receive

different scores from the earlier group’s paper.

– Data collector bias

– The person collecting data may have favours one group or

some characteristics some subject posses over another.

– Example, a teacher who favours strict classroom

management may rate student’s attention under different

teaching conditions with a bias toward one of the teaching

conditions.

– Resentful demoralization of the control group

– The control group may become discouraged because it is not

receiving the special attention that is given to the treatment

group. They may perform lower than usual because of this.

Once the researchers are confident that the outcome

(DV) of the experiment they are designing is the result

of their treatment (IV) internal validity, they determine

for which people or situations the results of their study

apply external validity

External Validity

– Are the results of the study generalizable (can be

applied) to other populations and settings

– Comes in two forms :

1) Population validity

2) Ecological validity

Population Validity

– Is the extent to which the results of a study can be

generalized from the specific sample that was

studied to a larger group of subjects

Ecological Validity

– Is the extent to which the results of an experiment

can be generalized from the set of environmental

conditions created by the researcher to other

environmental conditions (settings and conditions)

Threats to External Validity

– Pretest Sensitization

– A treatment might only work if a pre-test is given. Because they have

taken a pretest, the subjects may be more sensitive to the treatment. Had

they not taken a pre-test, the treatment would not have worked.

– Measurement of the DV

– A treatment may only be evident with certain types of measurements. A

teaching method may produce superior results when its effectiveness is

tested with an essay test, but show no differences when the effectiveness

is measured with a MCQ test. (maybe only works with MCQ test)

– First and foremost, an experiment must have internal validity.

If the researchers cannot certain that the results of the

experiment are dependent on the treatment, it does not

matter to which people or situations they wish to generalize

(apply) their findings. The importance of external validity is

reliant on having internal validity in much the same way that

the validity of a measurement instrument is reliant on the

instrument being reliable.

Different Research Designs

1) One-shot case study design

2) One-group pre test-post test design

3) Static group pre test-post test design

4) Static group comparison design

5) Randomized post test only, control group design

6) Randomized pre test-post test control group design

7) Randomized Solomon four-group design

One-shot case study design

One-group pre test-post test

design

Static group pre test-post test

design

Static group comparison design

Randomized post test only, control

group design

Randomized pre test-post test

control group design

Randomized Solomon four-group

design

– Each of the design described in this section has

advantages and disadvantages that influence the

studies internal and external validity.

Quasi is

“resembling”

Quasi experiment involve procedures that resemble those of true experiments.

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QUASI-EXPERIMENTAL RESEARCH

Include intervention or treatments but lack degree of “control”

e.g Lack of Randomization

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Quasi Experimental Designs

This type of design involves a treatment (manipulation ) and an outcome but lacks one of the other two properties that characterize a true experiment: randomization or a control group.

Example: if you want to study the effects of smoking on a variable, you cannot randomly assign people to smoking vs nonsmoking group.

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Quasi-experimental Methodology

In this methodology, the essential controls are not administered, such as treatments not being randomized. It is otherwise similar in structure to a true experimental design.

Types of Quasi Experiments

One group pre-test post-test design

Non equivalent control group design

Interrupted time series design

Time series with non-equivalent control group designs

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Why need quasi experiments ?

One group pretest- post test design representsPre –experimental design

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One group pretest – post test design

Comparison of treatment group and comparison group/ control group

Pre-test and post-test measures are used

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Non equivalent control group design

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Non equivalent control groups - other than the absence of randomly assigned groups, these designs are similar to experimental designs . However, lack of random assignment to control and experimental groups, can not assure that the groups are equal. The researcher must do everything possible to show that there are no differences. For example, a pretest may show that there is no difference. If the study is done on "after only data", this control is not present

Manipulation of independent variable

Pretest for all of the comparison groups

Post test for all comparison groups

No random assignment to the comparison groups (which as you can imagine is going to cause some problems with this design as compared to the strong “randomized” experimental designs.

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Essential features

In education, difficult to do true experiment because of the difficulty to have randomization, no control on the scheduling of treatment.

Lost part of the power due to lack of randomization (assignment of subjects)

Control of extraneous variable, difficult. External validity is enhanced ―> may be moving

toward real world setting

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Use when true experiment is not possible

Any design that does not randomly assigned subjects to the group is known as quasi-experimental designs.

Researchers do not use randomization but rely instead on other techniques to control threat to internal validity

CORRELATIONAL RESEARCH

Muhamad Aisamuddin Ridhuan

To discover c0-relationships

among two or more variables

To describe the relationship; to predict one variable from the

other

.

is considered type of observational research as nothing is manipulated by the

experimenter or individual conducting the research

Also known as

associational

research

Nothing was controlled by the researchers.

In other words, we can not make statements concerning cause and effect on the basis of this type of research.

Is often conducted as exploratory or beginning research. Once variables have been identified and defined, experiments are conductable.

also known as

associational

research

INTRODUCTIONAND

PURPOSE

.

also known as

associational

research

To describeCo-relationships that exist between two or

more variables(Explanatory Design)

also known as

associational

research

To identify relationship that can be useful in making predictions.

(Prediction Design)


more variables

also known as

associational

research

.

.

If we know vocabulary and school learning are correlated

We can predict that students with better vocabularies will usually learn more than students with limited vocabularies.

is considered type of observational research as nothing is manipulated by

the researcher


more variables

also known as

associational

research

To identify relationship that can be useful in making

predictions.

is considered type of observational research as

nothing is manipulated by the researcher

It often conducted as exploratory or beginning research.


more variables

also known as

associational

research


predictions.

is considered type of observational research as

nothing is manipulated by the researcher

In other words, we can not make statements concerning cause and effect on the basis of this type of research.

It often conducted as exploratory or beginning research.


more variables

also known as

associational

research


predictions.

To discover c0-relationships

among two or more variables

To describe the relationship; to predict one variable from the

other .

is considered type of observational research as nothing is manipulated by the

experimenter or individual conducting the research

Also known as

associational

researchIn other words, we can not make statements concerning cause and effect on the basis of this type of research.

Is often conducted as exploratory or beginning research. Once variables have been identified and defined, experiments are conductable.

INTRODUCTIONAND

PURPOSE

NTS

CORRELATION COEFFICIENTS

.

CORRELATION COEFFICIENTS

.

To determine the degree of relationship between two variables, researchers calculate a statistic called a

correlation coefficient.( represented pictorially by a scattergram )

.

Scattergrams

.

high scores on one are associated with high scores on the other, and that low scores on one are associated with low scores on the other.

.

high scores on the first thing are associated with low scores on the second or low scores on the first are associated with high scores on the second.

.

.

.

Correlational Research Design

1. Variables whose relationship is to be explored are identified and clarified.

.

2. Questions or hypotheses are stated


.


.


3. A sample is selected – preferably 30 or more

.


3. A sample is selected – preferably 30 or more

.


4. Measurements are obtained from each of the sample members on each of the variables being explored.

.


5. Correlations between and among variables are computed to determine degrees of relationship.

.

Example of research

.

Example of research

.

Example of research

What is survey ?

Method of gathering information

Measurement tools used in research to collect data

Measurement procedures that involving respondents by asking and answer the questions given

Types of survey :

a) Questionnaire

Type of survey

Questionnaire

Consist of a series of questions & other prompts

Usually the items used are essay or agree/neutral/disagree style

Questionnaire

Open-ended questions Closed-ended questions

Question ask respondent to

formulate their own

answer/opinions

Useful for descriptive study

Respondent pick an answer from given answer option

4 types of scales response:

Dichotomous – 2 options

Nominal – polytomous –more than 2 unordered options

Ordinal-polytomous – more than 2 ordered option

Bounded (continuous) –respondent is presented with a continuous scale

Definition of closed – ended questions Dichotomous – The questions that only have two possible answer ( Yes/No),

(Agree/Disagree) or (True/False)

Nominal – Polytomous – The questions that have more than two unordered answer (Education level)

Ordinal – Polytomous – The questions that have more than two ordered answer ( Answer has meaning = Rating scales from lowest

to highest/highest to lowest )

Bounded (continuous) – Questions should flow logically from the least sensitive to the most sensitive

Dichotomous questions Ordinal Questions

What is your household annual income?

1 Less that $5,0002 $5,000 to $9,9993 $10,000 to $14,9994 $15,000 to $19,9995 $20,000 to $29,0006 $30,000 to $39,9997 $40,000 to $49,0008 $50,000 to $75,0009 Over $75,000

11. What is your education level?

1 - High School or lower2 - Some College3 - College Graduate4 - Some Graduate School5 - Master's Degree6 - Doctorate

Nominal Questions

Example journal

Journal using questionnaire

Effectiveness of ICT Integration in Malaysian Schools: A Quantitative Analysis by Ghavifekr Simin and Ibrahim Mohammed Sani, (2015,August 8) Faculty of Education, University of Malaya.

Effectiveness of ICT Integration in Malaysian Schools.pdf

Interviews

Face to face

Telephone

Video – conferencing

Advantages Disadvantages

Can be developed in short period of time

Cost are effective and low

Capable of collecting data from large number of respondents

May not accurate/honest answer given by respondent

Survey question answer options could lead to unclear data

Selecting the Survey Method

There are 6 criteria of decisions:

1. Population issues

2. Sampling issues

3. Question issues

4. Content issues

5. Bias issues

6. Administrative issues

Population issues

• Can population be enumerated?

• Is the population literate?

• Are there language issues?

• Cooperation from respondents

• Demographic restrictions

Sampling issues

• What data is available?

• Respondents availability?

• Respondents target

• Can all members of population be sampled?

Question issues

• What type of questions can be asked?

• Level of difficulties?

• Will lengthy questions be asked?

Content issues

• Respondent knowledge about the issues asked?

Bias issues

• Can social desirability be avoided?

• Can false respondents be avoided?

Administrative issues

• Costs

• Facilities

• Time

• Personnel

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