Is it Possible to Remain Unbiased in Research?

A Tale of Two Generations: A Story from the Ancient Indus Valley Civilization
According to a famous researcher, it is impossible to conduct an unbiased research. This opinion asserting the impossibility of conducting a perfectly unbiased research appears plausible and correct. This assertion appears to be true because by an unbiased research, researchers usually mean a research that meets the trustworthy criterion, in case they are working in qualitative paradigm. When they work in quantitative paradigm, they consider that research of some quality that meets the requirements of reliability and validity.
What are trustworthiness, validity and reliability in the context of research-work? Basically validity means that what a researcher is concluding from the data actually follows from the data; there is some kind of logical connection between the premises, data and the conclusion arrived at on their basis. Moreover, if a researcher generalizes the conclusion and finding of a research over other similar cases; cases that were not studied during the research but fall under the same category in which the studies case fall, then by validity means it is logically valid to make such generalizations. Thus validity is of two types; internal and external validity.
Reliability actually means that the connection established between data and conclusion was not an accidental one. Rather than being an accidental connection, the connection between data and conclusion, established through a reliable research procedure, was essential and necessary. So, if someone else also wants to testify this necessity of relationship between data and conclusion, he or she can follow the procedure, and can verify the reliability of research method.
Trustworthiness, on the other hand is a criterion used to assess the quality of qualitative research, hence, it replaces the concepts of validity and reliability in qualitative research. Trustworthiness criterion includes credibility, dependability, confirmability and transferability. Credibility actually refers to the accurateness of reporting and interpreting of data by the researcher. Transferability means the possibility of generalizing the research results to other contexts. Dependability refers to the transparency of the steps involved in the research process, so an auditor can check each and every step involved in the research.  Confirmability refers to the objectivity of findings.
However, it seems really difficult to meet such standards exactly, and for a research to be perfect, these criteria should be fulfilled. Why such standards cannot be maintained in a research? The reasons are various. It is possible that the researcher brings in his own interpretation in the findings of research, for human beings cannot 100% keep their biases away, and according to a famous philosopher Heidegger, understanding is always already interpretive, and one interprets according to one’s fore-understanding, or previous understanding of the world.
This clearly shows that we cannot just simply put our biases away. Even if way say that something is longer than the other, or shorter, or equal to other, even in this case we are using our concepts that we have learned from our previous experiences, and we are only interpreting facts according to our concepts. Nietzsche has said that people interpret reality and then call it a fact, in his exact wordings, “there are no facts but interpretations.”
In certain cases one cannot even collect proper data, because of the power relationship that establishes between the researcher and the respondents. In such cases a researcher heavily influences the responses and the credibility of data vanishes.
In quantitative research, one is so very much preoccupied with theory one is testing, that one does not take into any instances that differ from it. One tries mould reality according to the concepts of theory, and concepts usually are arbitrarily imposed on reality. So, one can say that it is almost second to impossible to conduct an unbiased research, and the only thing that one can do ina research is this that one try to know clearly about ones biases.

According to famous philosopher , and the champion of modern hermeneutics, Hans George Gadamer, every judgment is biased, and the best thing that one can do is to know what are one's biases. If a researcher tries to know his or her own biases then this can help him a great deal in developing plausible research results.