Assertion (A): Random assignment is an important way to reduce systematic baseline confounding in experiments. Reason (R): Across repeated random assignments, it balances measured and unmeasured participant characteristics in expectation rather than guaranteeing identical groups in each experiment. Choose the correct relationship.
Both (A) and (R) are true and (R) is the correct explanation of (A).
Both statements are true, and the reason explains the assertion. Random assignment prevents systematic allocation based on baseline characteristics. Chance imbalance remains possible, especially in small samples, and randomization does not by itself prevent differential attrition or unequal treatment during the study.
Important Questions from Components of Research - Teaching
An investigator wants to conduct a study on orthopaedically handicapped children. The type of sampling to be used would be
Match each characteristic in List I with the validity evidence in List II.
List I: (a) Test scores predict later performance on an external criterion; (b) Scores support interpretation in terms of a theoretical psychological construct; (c) Test content represents the intended knowledge domain; (d) Scores relate to an appropriate external criterion measured at about the same time.
List II: (i) Content validity; (ii) Predictive validity; (iii) Concurrent validity; (iv) Construct validity.The element that differentiates between stratified and quota sampling techniques is
If a sample survey of the same 100 households is conducted in a particular village, annually for five years, the data so collected will be described as :
- Consider the following assertion and reason.
Assertion A: A concurrent validity coefficient can exceed a predictive validity coefficient when intervening changes weaken the relationship with the later criterion.
Choose the most appropriate answer.
Reason R: A higher validity coefficient alone does not establish that a test is more suitable for a particular purpose.
