Comparing and Contrasting Validity and Reliability - Essay Example

The same is the case with criminal justice. In order to generalize the results of any case, validity is used in two forms: internal and external. Internal validity is used initially in the crime investigation research process. The decision to support the valid facts by any variable inclusion or exclusion is termed as internal validity while its implementation is the external validity. In other words, external validity refers to those results which have very strong results of internally valid tests.

(Farrington et al, 2002, p. 13) On the other hand, reliability is all those measures that are utilized to achieve and repeat the same set of results acquired invalidity. Reliability guarantees and confirms the valid tests to be used ever again in criminal data analysis and findings.Example: Taking all the security measures to prevent women trafficking among the rural and urban populations may or may not generalize the problem because of the reason that the two populations are clearly different. Therefore the thing that concerns is that women trafficking crime measures in both populations reacts differently.

This can be achieved by testing those measures differently. In case a preventive measure is set in both the populations, its validity would be determined once according to their populations. Afterward, its reliability could be measured each time the standard results meet the acquired 'validity'. The main difference between a valid measure and reliability is the acquired set of results that prove an adopted measure's effectiveness. However, in reliability, the task is not limited to acquire valid measures but to maintain the proven set of results that have been set as a standard in 'validity'.

Example 1: Validity in a criminal offense (murder case) is determined by the truth and falsity of cause and effect. If X is murdered, is Y related to X If yes, then what is the ratio and statistical significance of their relationship If no, who are the people associated with person X, what is the ratio of their association In this case it is important to test the validity of the crime scene by detecting crime scene conditions and environment. The next time Z is murdered, the same valid techniques would be utilized to detect the offense, thereby implementing the reliability of the previous results.

Example 2: According to Farrington et al, in areas having a prevention program and a measure of crime, both measures at a single instance of the time depict lower crime rates than those areas having one and only measure at a time. (Farrington et al, 2002, p. 16) This could be validated by measuring crime instances before and after the above two measures. However, from this validity, we would look forward to achieving the same set of results that were acquired by adopting the two measures in any area. To this, the set of results would be reliable to check every time the measures are implemented.