Practical Research 2: Lesson 4

Manipulates variables and using control groups to determine cause-and-effect relationships.

Experimental Research Design

These are the simplest forms of experiments. There is no control group, so they’re often less reliable for determining causality.

Pre-Experimental Design

Involves one group that receives a treatment, and then is observed/measured afterward.

One-Shot Case Study

• Example: A class watches a documentary, then takes a test to see what they learned (no pre-test or comparison group).

Example of One-Shot Case Study

A single group is tested before and after the treatment.

One Group Pre-Test and Post-Test Design

Example: A class takes a quiz, receives a lesson, then takes the quiz again to measure improvement.

Example of One Group Pre-Test and Post-Test Design

These involve comparing groups, but without random assignment. They're more reliable than pre-experimental but still have limitations.

Quasi-Experimental Design

Compares two or more groups where participants are not randomly assigned.

Non-Equivalent Groups Design

Example: Comparing test scores of two different classes taught using different methods.

Example of Non-Equivalent Groups Design

A single group is measured multiple times before and after a treatment.

Time Series Design

Example: A class takes several quizzes over time, receives a new teaching method, then continues taking quizzes to observe trends.

Example of Time Series Design

These involve random assignment of participants to control and experimental groups, allowing for stronger conclusions about cause and effect.

True-Experimental Designs

Participants are randomly assigned. Both groups take a pre-test. One receives the treatment, the other doesn’t. Then both take a post-test.

Pre-Test/Post-Test Control Group Design

Example: Two randomly selected classes take a pre-test, one gets a new teaching strategy, then both take a post-test.

Example of Pre-Test/Post-Test Control Group Design

Participants are randomly assigned to groups. Only post-tests are given after treatment.

Post-Test Only Control Group Design

Example: Two groups are randomly selected, one receives a treatment, then both take the same test.

Example of Post-Test Only Control Group Design

These involve no manipulation of variables. Researchers observe and analyze what already exists.

Non-Experimental Research Design

Collects data from a large number of people using questionnaires or interviews.

Survey

Example: A school-wide survey on students’ study habits.

Example of Survey

Measures the relationship between two variables without determining cause and effect.

Correlation

Example: Studying the link between hours of sleep and academic performance.

Example of Correlation

Compares two or more groups to determine if there's a significant difference between them—without manipulation or control.

Difference

Example: Comparing the math grades of male and female students.

Example of Difference

2 Types of Quantitative Research Design

1. Experimental

2. Non-Experimental

3 Types of Experimental Research Design

1. Pre-Experimental

2. Quasi-Experimental

3. True-Experimental

2 Types of Pre-Experimental Design

1. One-Shot Case Study

2. One Group Pre-Test and Post-Test Design

2 Types of Quasi-Experimental Design

1. Non-Equivalent Groups Design

2. Time Series Design

2 Types of True-Experimental Design

1. Pre-Test/Post-Test Control Group Design

2. Post-Test Only Control Group Design

3 Types of Non-Experimental Research Design

1. Survey

2. Correlational

3. Difference