How can we respond to reviewers comment regarding the relationship among variables which have never been tested before? Is the literature support for proposed relationship among two variables compulsory?
Hermann Gruenwald is wrong. You have to respond to all questions asked by reviewers. I will not allow an article to go forward until all my questions in my reviews have been answered. You can just explain the relationship you found and then check the literature for similar studies. If there are none, just tell the reviewer, and you have an original study :)
Whenever possible, begin your response to each comment with a direct answer to the point being raised. You can provide background information, but you should do so after giving your primary response. Provide a “yes” or “no” answer whenever possible. When the reviewer is correct, state so in your response Muhammad Khayyam
In my view, you don't have to agree with each and every question raised by reviewers. Sometimes you understand your study more than the reviewer, so if the answer is "No", go straightforwardly with "No" and explain your point but in a polite way.
In my opinion, you can respond with your understanding and if you can support your answer with data from the literature, I think this can be fair enough.
First you should try to find some prior literature (either supports your results or not); nevertheless, if you don't find then you should state straightly in a gentle way that it is the empirical study.
it's better to verify in the LR that can support you to answer or make correlation between variables and insert the table. Even if there's no relationship, or non siginificant results will support your answer.
When reviewer ask to add the relationship, his sure that there's a relationship...
Consider a reviewer as a perso who will support your paper and will help you and support you to submit a strong paper for final publication.
A reviewer is like a judge in a court. You can't challenge his comments or decisions. You have to answer his every comment and provide justification with evidence if you can't make the necessary amendments.
Try to understand truly the reviewer, be polite, and meet her/his demands as long as you believe and agree with s(he). If you don't agree with him/her, you should defend your opinions with your arguments. You had better ask the reviewer what you don't understand instead of ignoring them and ask more clarification.