"The Nobel Memorial Prize in Economic Sciences, commonly referred to as the Nobel Prize in Economics,[2] is an award for outstanding contributions to the field of economics,[3] and generally regarded as the most prestigious award for that field."
That is not a Nobel prize it is a Nobel MEMORIAL prize. Nobel did not create it in his will like the rest of the prizes. There are a number of people who oppose liking economics with a study "worthy" of his money.
You can take your own side in that, but do understand that a different side exists.
While it is technically true that Alferd Nobel did not provide for a prize in Economics in his will, there is The Sveriges Riksbank Prize in Economic Sciences (1). This was funded in Nobel's memory by a Swedish central banker.
It is administered by the Nobel Foundation - just like the other prizes.