Criminal Justice Coursework

Week 2 DQ1
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Institutional Affiliation

Explain the differences in variables related to internal versus external validity
The term validity refers to the degree of correctness or accuracy in particular research. There are two primary factors involved in the validity of the study. These include internal and external elements. The internal factors mainly focus on internal validity whereas external factors impugn the external validity of the research findings (Hagan, 2012). Some of the variables related to internal validity include history, testing, instrumentation, selection bias, statistical regression, experimental mortality, and selection; maturation interaction (Hagan, 2012). On the other hand, there are specific factors that are related to external validity. Some of these factors include testing effects, selection bias, multiple –treatment interference, and reactivity. These variables differ in various perspectives.
Variables Related to Internal Validity
These are internal factors which threaten or alter the internal validity of the research.
History: These are particular events which can happen at the time of the study leading to the production of results. For instance, bad weather in a specific city may affect crime rates in a particular season.
Maturation: These are psychological or biological changes from the respondent which are not a result from variable under experiment. For instance, grading may result to change in crime rates in a place.
Testing: This is foreknowledge and bias which one can introduce to the respondent because of protest.

The protest bias may alter the validity of the results.
Instrumentation: The changing in measuring instrument from the first evacuation period to the final period may alter the validity of the research, for instance, observers, interviewers, questionnaires among others.
Statistical regression: This is the tendency of the selected group for the study to move towards the mean on the second testing.
Selection bias: In case the researcher chooses the non-equivalent groups when making a comparison, selections bias comes in.
Experimental mortality: It refers to the expected loss of a subject when one is studying the same group over a long duration.
Selection-maturation interaction: This occurs when combining the impacts of any variables contribute to the obtained results. For instance, communication of differential maturation groups with selection bias.
Variables Related to External Validity
These are competitive causal factors that can impact the generalization of findings from a study beyond the studied group.
Testing effects: Refer to the tendency of protests to alter the respondent’s naiveté concerning the studied variables (Hagan, 2012). Eventually, the predictability becomes affected. The results of testing effects complicate the ability to generalize the responses.
Selection bias: In case there is non-representative study group selection, the results become invalid, making it hard to generalize the population.
Reactivity: The reactivity mainly results in strange or typical behavior on the subjects. It leads to abnormal results.
Multiple-Treatment interferences: When more than a single predictor variable is utilized on the same subject, the outcome may be altered.
Conclusion
The internal validity concentrates on whether another variable apart from X might have probably contributed to changing the Y (independent variable). The external validity focuses on other variables which can affect or limit the generalization of findings from a study involving larger populations. The internal variables include history, testing, maturation, instrumentation, selection bias, experimental mortality, selection, and statistical regression. On the other hand, external variables include testing effects, multiple-treatment interference, reactivity, and selection bias. All these variables differ, but they eventually affect the result from a study.
Reference
 Hagan, F. (2012). Grand Canyon University – Digital Resources. Retrieved from http://www.gcumedia.com/digital-resources/pearson/2011/essentials-of-research-methods-for-criminal-justice_ebook_3e.php