PSY3211 – Research Methods and Data Analysis in Psychology
Need an original paper done on this topic?
Order Now
Precedent involves using the same participants as prior researchers. Though results may be valid, the nature of participants makes it difficult to generalize to other groups hence low reliability. Availability involves using participants because they are readily available. The results are valid and easy to reproduce hence reliable.
A heterogeneous sample is one where every member has a different value for the characteristic the researcher is interested in. Heterogeneous samples allow for generalizability. The sample does not revel which variability is impacting the dependent variable. A homogenous sample is one where participants have similar or identical characteristics. Having similarities between participants creates less error in results, hence greater significance. The sample is limited in that it does not represent the whole population but only a select group.
One study that I could run using a double-blind approach would be one involving patients with Alzheimer’s. The researcher does not know which patients the real drug or the placebo is administered. The participants are also not told. A double-blind approach is needed in the study because, a researcher’s feeling or knowledge of the patient’s history may affect the way he administers the drug. To eliminate the researcher’s bias, she must be excluded from the process. A single-blind would not be the best option as the researcher may choose patients whom they feel the drug will have higher chances of success.
In a single-blind test, the participants are not told because they might behave as if the drug was working. By not telling them, the researcher eliminates their likelihood of behaving according to expected results. Double-blind is not needed because the researcher needs to know what to look for in his observation.
Between homogenous and heterogeneous samples, which one is more valid and reliable?
Both yield valid results however homogenous results are collected from a limited group hence less generalizable. That is, a homogenous sample is can be hard to reproduce. A heterogeneous sample is therefore more valid and reliable.
