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Behavioral Therapy

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Abstract
When conducting psychological research, it is difficult to gain access to large and normally distributed samples (Gravetter & Wallnau, 2006). Fortunately, there is a statistical test employed when making comparison between two independent groups that have no requirement for large and normally distributes samples; the Mann-Whitney U test. This paper provides a summary of the test, an explanation of the logic that underlies the test and its application, and the forces and weaknesses of the test. For instance, one of the major limits of this test is the type I error which is rather amplified in a heteroscedasticity situation.
Generally psychological studies comprise small samples. For instance, clinical psychology researchers more often …show more content…

An experimenter read there exist an antibiotic that is often tested, has been documented and well versed for aiding in information storage in the memory. This experimenter is also aware, using scientific reports, of guidelines and reports that behaviour therapy carries an efficacy in treating social phobia. The relation is that behavioural therapy involves integrating new behaviours hence storage of information (Gravetter & Wallnau, 2006).
The number social phobia symptoms were studied after therapy. Two groups of individuals who exhibited social phobia were investigated and compared. The first group was given behavioural therapy while the second the therapy was combined with antibiotics. Both groups exhibited a decrease in the symptoms of social phobia after every therapy session. The symptoms were measured and tests run to establish whether the combined therapy was more effective than the behavioural one alone (Gravetter & Wallnau, 2006). That is, the experimenter wished to make a comparison between random variables that had distribution functions that ere continuously cumulative. The hypothesis is that the variables are stochastically equal against the alternative that C (symptoms under combined therapy) is stochastically smaller than B (symptoms under behavioural therapy). Unfortunately, the subject number was small and there was nothing in the data indicating the normal distribution of …show more content…

In terms of the forces, the test does not depend on distribution assumptions; the data distribution of the population does not need to be postulated. The test can be employed when the normality conditions are either not met or cannot be realised by transformations. It is also applicable in a small sample scenario and for semi-quantitative data. In short, there are few constraints that apply to the Mann- Whitney U test (Hollander, Wolfe & Chicken, 2013).
This non parametric test is one of the most powerful where the statistical power and the likelihood of rejecting the null hypothesis correspond. This means that the test carries a rather good probability of giving results that are statistically significant in a case where the alternative hypothesis is applicable to the measured reality (Hollander, Wolfe & Chicken, 2013). Even when the samples are average sized, or when the data can be measured using t test, the Mann-Whitney test, as compared to the student’s t test, has a 95% statistical power. When compared with the t test, the Mann Whitney U test is less likely to give statically wrong results in the event of one or more extreme values in the

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