Final answer:
Using self-reported data from a convenience sample limits the ability to generalize to a larger population due to inaccuracies in responses and lack of representativeness. Internet surveys often have biases, and representativeness is crucial for generalizability. Expansion of the sample to include a greater variety of conditions is necessary for nationwide generalizations.
Step-by-step explanation:
When we use self-reported data from a convenience sample, there are several limitations that hinder the ability to generalize findings to a larger population. One issue is the accuracy of self-reported responses. Participants may not always provide accurate responses due to a tendency to lie, misremember, or answer in a socially desirable manner. For instance, they might underreport alcohol consumption. Additionally, convenience samples suffer from a lack of representativeness since they consist of individuals who are readily available rather than a cross-section of the entire population.
Another concern is that large samples, even if they seem substantial, can be biased. For example, an internet survey might primarily attract those with internet access and the inclination to respond, skewing the results. Furthermore, the Pew Research Center notes that getting people to answer surveys can be challenging, which may affect sample representativeness and the ability to generalize findings.
When discussing a sample's representativeness, factors such as geographical diversity should be considered. A sample from one state, like Kentucky, would not account for behaviors or attitudes that could be significantly different in other regions. Hence, the study's findings cannot be assumed to apply to the entire nation without expanding the sample to reflect a wider range of conditions and demographics.