Ontology and Epistemology

What is ontology and how is it relevant to research?
Ontology is an aspect of research related to how research philosophy is viewed, being tied an related to the nature of reality. “Ontology is a system of belief that reflects an interpretation of an individual about what constitutes a fact.” (https://research-methodology.net/research-philosophy/ontology/)
It basically relates to objectivism and subjectivism, how different things are viewed depending on the nature of that thing and personal perspective, “the fundamental nature of existence” (https://theperformancesolution.com/earth-ontology-epistemology/). Understanding the nature of the research subject can be used in research by accurate understanding and filtering of the data gathered, and using the correct methods to gather data based on that understanding.

What is epistemology and how is it relevant to research?
Epistemology relates more to sources of information than the information itself and can be used to categorise what the researcher considers knowledge or not based on that source (https://research-methodology.net/research-philosophy/epistomology/). It comes after ontology, which is based in identifying facts, as a sort of filter to those facts. Epistemology is important to research because of this – it’s not just about identifying facts people consider to be true/reality, it’s determining which of those facts are valid to the research and accurate once the source of that knowledge is analysed and understood. It’s a method of filtering weak information, so research only attributes strong data to its analysis and potentially makes that research more accurate overall by ensuring ‘false’ or groundless data doesn’t get used. How exactly this is done will vary by specific method/perspective, positivism or interpretivism. Positivism involves only accepting objective and verifiable facts, while interpretivism rejects absolute facts under the assumption that those facts aren’t based on objective truth with the research itself being based on the researchers interpretation of it. (https://theperformancesolution.com/earth-ontology-epistemology/)

What is the connection between the two in a research context?
As mentioned in Epistemology, ontology is used to identify facts and then epistemology is used to filter what facts are taken into account for the research, and which sources of data are considered valid. Both are required for successful research, as without reality-based facts (subjective or objective) there would be no data to build the research from, but at the same time not everything is relevant to research or even grounded in reality so there is a need to verify and filter what data should be considered for the research once it has been identified.
The diagram below shows this link, and how it relates to later steps in research overall.

Ontology-and-epistmeology-v4 (Diagram from http://salmapatel.co.uk/academia/the-research-paradigm-methodology-epistemology-and-ontology-explained-in-simple-language)