The reason why the authors included Feldman in their study was that Feldman kept rigorous data on his business.
<h3>What is a Research Study?</h3>
This refers to the systematic findings that are done about a particular thing to find out the reasons for its occurrence.
Hence, we can see that from the complete text, there is the <u>narration</u> of the research that was done and the reason for the inclusion of Feldman into their study which was because of his rigorous data.
Read more about research here:
brainly.com/question/25959526
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