When and where was the world's first self-checkout system invented and implemented in retail?

The retail landscape has been transformed by numerous technological inventions over the decades. One particular innovation has dramatically changed how customers complete their shopping experience, reducing wait times and labor costs for retailers. This trivia question explores the origins of a now-ubiquitous retail technology that represented a significant leap forward in store automation and customer empowerment.

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1992 by Howard Schneider, first implemented at Price Chopper supermarket in New York
1987 by IBM, first implemented at Walmart in Arkansas
1998 by NCR Corporation, first implemented at Kroger stores in Cincinnati
2001 by Amazon, first implemented at Whole Foods as a prototype system