Advantages
The researcher has a proven idea and scientific background;
It is used in addition with traditional research and theory in order to authenticate it through various experiments and observations;
The results are more competent and authentic;
It provides the researcher with facts;
The researcher is able to control multiple variables;
Helps to increase the internal validity of the research;
Helps with understanding nature of these problems;
A theory contains concepts, variables, facts, principles and propositions – that is a great bonus when it comes to doing the practical part of the research.
Disadvantages
Very time consuming;
There could be a necessity to conduct research at different locations – can be expensive;
Collecting and processing data from various sources can be a challenge;
Problems with understanding if the information sources are truthful.
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