Final answer:
The researcher uses matched samples with a paired design to compare attitudes between 50 pairs of husbands and wives, ensuring that each couple is considered a matched pair and accounting for the dependent relationship between their data.
Step-by-step explanation:
The researcher is making use of matched samples with a paired design when comparing 50 pairs of husbands and wives on a variety of attitudes.
This type of study involves comparing two samples that are dependent; here, each husband is matched with his wife, creating pairs. Since participants didn't just interact randomly with one another but have a specific relationship, using matched pairs accounts for the inherent connection between the data collected from the two members of each pair. In contrast, an independent samples design would be used if the two groups had no such relationship and individuals in one group would not be systematically related to individuals in the other group.
In addition to the design, the sampling method is crucial for the validity of the results. In this context, simple random sampling is important to ensure that each pair has an equal chance of being included in the study. This helps in reducing bias and makes the study results more generalizable.