Introduction to Quantitative Research Methods

Introduction to Quantitative Research Methods

Content

1. Introduction

2. Key Concepts and Terminology

3. Research Questions and Hypotheses

4. Sampling Techniques

5. Data Collection Methods

6. Data Analysis Techniques

7. Ethical Considerations

8. Conclusion

Introduction

What is quantitative research method?

Quantitative Research

• Typically involves counting or measuring

• Often statistical tests are applied to detect or confirm trends

• Purpose is to get clear-cut, precise and accurate results, factually reflecting the situation under study.

• Formal, objective, rigorous, systematic process for generating information.

• Questionnaire is one of the popular tools for the quantitative research

Let's test your knowledge

Multiple Select

Select all that applies to quantitative research.

• Polls

• Numerical Data

• Questionnaires

• Statistics

Key Concepts and Terminology in Quantitative Research

Independent Variable (IV)

• The variable that is controlled or manipulated by the researcher

• The variable that is thought to have some effect upon the dependent variable

• The one difference between the treatment (experimental) and control groups

Dependent Variable (DV)

• The outcome

• That which is influenced or affected by the dependent variable

Let's test your knowledge

Multiple Choice

In a study examining the relationship between hours spent exercising per week and weight loss, which of the following are the independent and dependent variables?

• Independent: hours spent exercising; Dependent: weight loss

• Independent: weight loss; Dependent: hours spent exercising

• Both hours spent exercising and weight loss are independent variables

• Both hours spent exercising and weight loss are dependent variables

Multiple Choice

In a study exploring the impact of social media usage on mental health among teenagers, which of the following are the independent and dependent variables?

• Both social media usage and mental health among teenagers are independent variables

• Both social media usage and mental health among teenagers are dependent variables

• Independent: mental health among teenagers; Dependent: social media usage

• Independent: social media usage; Dependent: mental health among teenagers

Multiple Choice

In a study investigating the effect of different amounts of sleep on students' exam scores, which of the following are the independent and dependent variables?

• Independent: students' exam scores; Dependent: different amounts of sleep

• Independent: different amounts of sleep; Dependent: students' exam scores

• Both different amounts of sleep and students' exam scores are independent variables

• Both different amounts of sleep and students' exam scores are dependent variables

Hypothesis

• Hypothesis = an idea that will be tested through systematic investigation

• A hypothesis is a testable statement or prediction about the relationship between two or more variables in a research study.

• A researcher’s prediction of what outcomes will occur

• Fits survey research, also called “Hypothesis Testing”

There are several types of hypotheses:

1. Null hypothesis (H0)

2. Alternative hypothesis (H1 or Ha)

3. Directional hypothesis

4. Non-directional hypothesis

Null hypothesis (H0)

• The null hypothesis posits that there is no significant relationship or difference between the variables being studied. It represents a statement of no effect, which the researcher aims to either reject or fail to reject based on the study's findings. In many cases, researchers are more interested in disproving the null hypothesis than in confirming it.

• Example: There is no significant difference in exam scores between students who study with background music and those who study in silence.

Alternative hypothesis (H1 or Ha)

• The alternative hypothesis suggests that there is a significant relationship or difference between the variables. It is the opposite of the null hypothesis and represents the prediction that the researcher seeks to confirm through the study.

• Example: Students who study with background music have significantly higher exam scores than those who study in silence.

Directional hypothesis

• A directional hypothesis predicts the specific nature of the relationship between the variables, such as whether one variable will increase or decrease as the other changes. This type of hypothesis is used when there is a strong theoretical or empirical basis for making a specific prediction.

• Example: Students who study with background music have significantly lower exam scores than those who study in silence.

Non-directional hypothesis:

• A non-directional hypothesis predicts that there will be a significant relationship between the variables but does not specify the direction of the relationship. This type of hypothesis is used when there is insufficient evidence or theory to predict the specific nature of the relationship.

• Example: There is a significant difference in exam scores between students who study with background music and those who study in silence, but the direction of the difference is not specified.

Let's test your knowledge

Multiple Choice

A researcher is investigating the impact of a new protein supplement on muscle gain in athletes during an 8-week training program. Which of the following statements represents the null hypothesis?

• The new protein supplement significantly increases muscle gain in athletes during the 8-week training program.

• The new protein supplement significantly decreases muscle gain in athletes during the 8-week training program.

• The new protein supplement has no significant effect on muscle gain in athletes during the 8-week training program.

• There is a significant difference in muscle gain between athletes who take the new protein supplement and those who do not during the 8-week training program.

Multiple Choice

A researcher is investigating the impact of a new teaching method on students' math performance. Which of the following hypotheses represents a non-directional hypothesis?

• The new teaching method has no significant effect on students' math performance.

• The new teaching method significantly improves students' math performance.

• The new teaching method significantly reduces students' math performance.

• There is a significant difference in students' math performance between those taught using the new method and those taught using the traditional method.

Multiple Choice

Read the following statements and identify which is a research objective, research question, and research hypothesis:

A. What is the relationship between class size and student performance in mathematics?

B. To examine the impact of class size on student performance in mathematics. C. Class size has a significant effect on student performance in mathematics.

• Research Objective: A; Research Question: B; Research Hypothesis: C

• Research Objective: B; Research Question: A; Research Hypothesis: C

• Research Objective: C; Research Question: B; Research Hypothesis: A

• Research Objective: A; Research Question: C; Research Hypothesis: B

Multiple Choice

Title: The Impact of a Flipped Classroom Teaching Approach on Student Performance in High School Science Classes

Question: Based on the research title, identify which statement best represents the research objective, research question, and research hypothesis:

A : To evaluate the effect of a flipped classroom teaching approach on student performance in high school science classes.

B : Does a flipped classroom teaching approach significantly improve student performance in high school science classes?

C : Students in high school science classes taught using a flipped classroom approach will show significantly better performance compared to students taught using traditional methods.

• Research Objective: A; Research Question: B; Research Hypothesis: C

• Research Objective: B; Research Question: A; Research Hypothesis: C

• Research Objective: C; Research Question: B; Research Hypothesis: A

• Research Objective: A; Research Question: C; Research Hypothesis: B

Open Ended

Title: The Effect of Mindfulness Meditation on Reducing Symptoms of Anxiety in College Students

Question: Based on the research title, list down the research objective:

Open Ended

Title: The Effect of Mindfulness Meditation on Reducing Symptoms of Anxiety in College Students

Research Objective: To investigate the impact of mindfulness meditation on reducing symptoms of anxiety in college students.

Question: Based on the tittle and research objective, list down the research question:

Open Ended

Title: The Effect of Mindfulness Meditation on Reducing Symptoms of Anxiety in College Students

Research Question: How does mindfulness meditation affect symptoms of anxiety in college students?

Question: Based on the research question, list down the research hypothesis:

Title: The Effect of Mindfulness Meditation on Reducing Symptoms of Anxiety in College Students

A. Research Objective: To investigate the impact of mindfulness meditation on reducing symptoms of anxiety in college students.

B. Research Question: How does mindfulness meditation affect symptoms of anxiety in college students?

C. Research Hypothesis: College students who practice mindfulness meditation will experience a significant reduction in symptoms of anxiety.

Reliability

• The ability of a measurement tool to yield consistent results over time or under similar conditions

• Internal Consistency Reliability: This refers to the extent to which different items or measures within a test or questionnaire consistently measure the same construct. To assess internal consistency reliability, researchers use statistical methods such as Cronbach's alpha to determine the degree of agreement between different items in a test

Content Validity

• The extent to which the items on a testing tool (that being used to measure the dependent variable) reflect all of the facets being studied.

• Degree to which a measure or test covers all aspects or dimensions of the concept being measured.

• To establish content validity, researchers may use different techniques, such as expert judgment, literature review, or pilot testing, to ensure that the items in the measure reflect the construct being measured.

Construct Validity

• The extent to which the testing tool measures what it is supposed to measure.

• Refers to the extent to which a measure or test accurately assesses the underlying theoretical construct it is intended to measure. In other words, a measure has construct validity if it truly measures the concept or construct it claims to measure

• Relationship between the items on the tool and the dependent variable.

• To establish construct validity, researchers may use different techniques, such as convergent validity (the extent to which different measures of the same construct are related) and discriminant validity (the extent to which different measures of different constructs are not related) to demonstrate that the measure accurately reflects the theoretical construct being measured.

Objective Evaluation

⚪ Rigorous

⚪ Expository

⚪ Time Consuming

focuses on the accuracy of the measure in assessing the intended construct

Construct validity

focuses on the comprehensiveness of a measure

​Content Validity

IN SHORT

Survey Research

⚪ Use set of predetermined questions

⚪ Collect answers from representative

sample

⚪ Answers are categorized and

analyzed so tendencies can be
discerned

General steps for designing and administering a questionnaire survey:

Step 1: Define the research problem and objectives:

• Determine the research questions and objectives that the survey will address.

Step 2: Identify the target population:

• Define the population or group of people that the survey will target.

Step 3: Develop the survey questions:

• Develop clear, concise, and relevant questions that address the research objectives.

• Use appropriate question formats, such as closed-ended, open-ended, or rating scales.

Step 4: Pilot test the survey:

• Test the survey with a small group of people to identify any issues or problems with the questions or format.

General steps for designing and administering a questionnaire survey:

Step 5: Administer the survey:

• Choose an appropriate method for administering the survey, such as online, paper-based, or in-person.

• Determine the sample size and method of sampling.

• Obtain informed consent from the participants.

Step 6: Analyze the survey data:

• Clean and code the survey data.

• Conduct descriptive and inferential statistical analyses to answer the research questions.

Step 7: Report and interpret the findings:

• Summarize the survey findings in a clear and concise report.

• Interpret the findings and draw conclusions based on the research objectives.

Step 2: Identify the target population:

Identify the Target Population

• In this step, you will define the population or group of people that the survey will target.

• The target population should be clearly defined and relevant to the research objectives.

• The sample size and method of sampling will depend on the characteristics of the target population.

• Examples of target populations include:

  • Customers of a specific product or service

  • Employees of a particular organization or industry

  • Residents of a certain geographic area

  • Members of a particular demographic group (e.g., age, gender, income)

Sampling techniques

are methods used by researchers to select a subset of individuals or units from a larger population to be included in a study.

​Parametric and non-parametric sampling

• Parametric sampling assumes that the data follows a normal distribution and uses inferential statistics to make inferences about the population.

• This type of sampling requires that certain assumptions be met, such as homogeneity of variance and independence of observations.

• These parametric sampling techniques are commonly used in quantitative research studies to ensure that the sample is representative of the population and to estimate population parameters with a high level of precision.

• Examples of parametric statistical tests include t-tests, ANOVA, and regression analysis.

• Here are some examples of parametric sampling techniques: Simple Random Sampling, Stratified Sampling, Cluster Sampling

Here are some common sampling techniques used in research:

1. Simple Random Sampling: This is a commonly used parametric sampling technique in which each individual or unit in the population has an equal chance of being selected for the study. Simple random sampling can be used to estimate population parameters, such as means and proportions.

2. Stratified Sampling: This parametric sampling technique involves dividing the population into subgroups or strata based on relevant characteristics, such as age or gender, and then randomly selecting individuals from each stratum. Stratified sampling can be used to reduce sampling error and increase the precision of estimates.

Here are some common sampling techniques used in research:

1. Cluster Sampling: This parametric sampling technique involves dividing the population into clusters or groups based on geographic location or other relevant characteristics and randomly selecting clusters to include in the study. Cluster sampling can be useful when the population is widely dispersed geographically.

2. Systematic Sampling: This parametric sampling technique involves selecting individuals from the population at regular intervals, such as every tenth person. Systematic sampling can be more efficient than simple random sampling when the population is large and there is a defined list of individuals or units.

cont

• Non-parametric sampling, on the other hand, does not require that the data follows a normal distribution and can be used for data that is not normally distributed or has outliers.

• This type of sampling does not make any assumptions about the population and uses alternative statistical tests that are robust to violations of normality and other assumptions.

• Non-parametric sampling techniques do not require that the data follows a normal distribution and can be used for data that is not normally distributed or has outliers. However, non-parametric techniques may be less powerful than parametric techniques and may require larger sample sizes to achieve the same level of precision.

• Examples of non-parametric statistical tests include the Wilcoxon rank-sum test, the Kruskal-Wallis test, and the Mann-Whitney U test.

• Convenience Sampling, Snowball Sampling, Quota Sampling, Purposive Sampling

cont.

1. Convenience Sampling: This non-parametric sampling technique involves selecting individuals who are readily available or easily accessible for the study. Convenience sampling can be useful for studies with limited time or resources, but it may not be representative of the population.

2. Snowball Sampling: This non-parametric sampling technique involves selecting initial participants who then recruit other participants from their network. Snowball sampling can be useful when the population is hard to reach or when the sample size is small.

cont.

1. Quota Sampling: This non-parametric sampling technique involves selecting individuals based on pre-determined quotas for different subgroups of the population. Quota sampling can be useful when the researcher wants to ensure that the sample is representative of different subgroups of the population.

2. Purposive Sampling: This non-parametric sampling technique involves selecting individuals who meet specific criteria relevant to the research question or objectives. This can be useful for studies that require specific expertise or experiences, but it may not be representative of the broader population.

Step 3: Develop the survey questions

Type of Questions

•Factual:Age, gender, education, experience

(often used to investigate relationship)

•Informative:What respondents know

about a given topic (How do you come to
know about the availability of e-journals?)

•Attitudinal/Opinion:To obtain info about

respondents’ beliefs, feelings, values (Do
to agree that current copyright law is fair?)

•Self-perception:Allows subjects to

compare their ideas or actions with others
(How active are you in the community work?
How will you describe your computing skills?)

Type of Questions

•Standard of Action:How respondents will

act in a situation (For which party you will vote
in the next election? Will you join the organ
donation society? )

•Projective Questions:Allow respondents to

answer in an indirect manner by imposing
their feelings, attitudes or beliefs on others
(Are most of the Singaporeans quitters or stayers?
Are students happy with the grading scheme?)

Structured Questions

Dichotomous: yes/no, true/false, agree/disagree

Multiple Choice:

nWhat sources do you use for writing term reports? (check all that apply)

nHow many hours do you exercise per week (check only one response)

nHow satisfied are you with the quality of canteen ‘A’ food?

Contingency:

nDetermine if the respondent is qualified to answer a subsequent question)

nDo you use databases available through iGems? (If no, please move to question 15)  *

nHave you participated in DIS orientation? (Yes/No) (If yes, how effective was this briefing? (Very effective, effective, ineffective …)

Scaling Responses

•Likert-type Scale:Each response is

assigned a numeric ranking based on a
continuum that contains predetermined
units of measurement

•Designed to show a differentiation among

respondents opinions

• How important is …. (very important, important ….)

• How adequate are …. (v. adequate ……..inadequate)

• How frequently do you ... (frequently … infrequently)

Scaling Responses

•Semantic Differential Scale:Provides a set

of bipolar adjective pairs

Q.How would you rate performance of the

Income Tax staff?

1 2 3 4 5 6 7
Bad … … … … … … … Good
Unfair … … … … … … … Fair
Harsh … … … … … … … Gentle

Scaling Responses

• Respondents are expected to rank responses

according to their importance/ preference

• Should be used carefully as many respondents

face difficulty in understanding/responding

• Only use a short list of responses
Q.What sources do you prefer for writing term reports?

Please rank them according to …… (1= most preferred;
7= least preferred)

--- Books

--- Encyclopaedia

--- Friends
--- Internet
--- Journals
--- Lecture notes
--- Personal collection

Rank-order or Comparative Ranking Scale

Question Placement

• Opening questions -start with easy non

threatening questions

•Sequence -according to the research topic,

logical flow

•Sensitivequestions-should be asked only

after trust is developed

•Difficultquestions -more difficult

questions should be asked at the end

•Personal Data –age, gender, qualification,

experience

Mapping Survey Questions

Res. Objective 1

Question

Question

Question

Res. Objective 2

Question

Question

Res. Objective 3

Question

Question

Question

The End