Makes you an informed researcher/applicant
Provides perspective by situating your work within the knowledge base (theory & practice) of your field
Supports your research idea/proposal or identifies a gap needing further research
Provides ideas for research design; for example, quantitative or qualitative approaches or instruments to use
Provides credibility to grant proposals
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"derived from or denoting experimentation or systematic observations as the basis for conclusions or determinations, as opposed to speculative, theoretical, or exclusively reason-based approaches"
Other types of publications you will encounter: