Match the Following

Match List –I with List –II

List I threat to Internal validity	List II Situation/Explanation
A.	Maturation	I.	The emotional tirade of a teacher
B.	History	II.	Volunteers in experimental group
C.	Testing	III.	Subjects become tired
D.	Selection bias	IV.	Effect pre test of proficiency in subsequent tests

Choose the correct answer from the options given below:

Correct option is C

The correct answer is (c) "A-III, B-I, C-IV, D-II."
Explanation: The correct matching of threats to internal validity with their corresponding situations or explanations is as follows:
· Maturation (A-III): Refers to the internal changes within participants over time that could affect the outcomes of an experiment. For example, subjects might become tired, bored, or more experienced during the course of a study.
· History (B-I): Refers to external events that occur during the course of an experiment, which could influence the outcomes. For instance, an emotional tirade of a teacher during an experiment could introduce external variables affecting participants' responses.
· Testing (C-IV): This threat occurs when the pre-test affects the performance on the subsequent tests, possibly due to practice effects or sensitization to the test material.
· Selection Bias (D-II): Occurs when participants are not randomly assigned to groups, leading to differences that affect the outcome. For instance, volunteers in the experimental group might have different characteristics than those in the control group.
Information Booster:
1. Internal Validity: Refers to the extent to which an experiment accurately establishes a cause-and-effect relationship between the independent and dependent variables, free from confounding factors.
2. Maturation: Changes within participants, such as aging, fatigue, or learning, that occur over time and might influence the experimental results, posing a threat to internal validity.
3. History: External events that coincide with the experiment can introduce confounding variables that affect the outcomes, compromising the internal validity of the study.
4. Testing Effects: Repeated testing can lead to participants becoming more familiar with the test material, potentially improving their performance independent of the experimental treatment.
5. Selection Bias: When groups are not equivalent at the start of an experiment due to non-random assignment, this can lead to differences in outcomes that are not attributable to the treatment effect.
6. Controlling Threats to Validity: Researchers can use techniques such as randomization, control groups, and blinding to minimize threats to internal validity and ensure that the observed effects are due to the manipulation of the independent variable.
Additional Information:
· Maturation vs. History: Maturation refers to internal changes within participants over time, while history refers to external events that affect all participants in the study.
· Testing Effects: Can be reduced by using different forms of the test or by implementing a control group that does not receive the pre-test.
· Selection Bias: Can be mitigated by ensuring random assignment of participants to different experimental conditions.
Key Points:
· Internal validity is crucial for establishing the credibility of experimental findings.
· Understanding the various threats to internal validity helps researchers design more robust experiments.
· Proper controls and experimental design can mitigate these threats, ensuring that the results are attributable to the independent variable.