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The two reasons why psychologists use a systematic method for collecting and analyzing research data are: 1. This helps them to do exhaustive investigation, inquiry and or examination of facts or a problem situation at hand in a systematic and clear sequence so as to be able to discover or make concrete interpretations from the research 2. Credible research findings usually requires replicability in that given the same situation or problem, same research can be conducted and get the similar results, a fact which requires a systematic method of data collection and analysis.
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