“It depends on your frame of reference,” Cathy O’Neil blogged as her response if asked whether the Sun goes around the Earth. “If I’m standing on the Earth, and I look up in the sky, I will observe the Sun going around the Earth in a wobbly path. Although it would be quite a bit simpler to understand the model of the solar system whereby the Earth and other planets revolve around the Sun and spin while they do so.”
While O’Neil was poking fun at the silliness of simplistic poll questions, her point of view about our frame of reference is an important one. While it has been centuries since the Copernican Revolution marked the paradigm shift of accepting the fact that the Earth revolves around the Sun, we still use the terms sunrise and sunset. As O’Neil noted, the illusion of a rising and setting Sun results from our rotating frame of reference on the Earth’s surface, whereby Earth’s rotation makes it appear to us as if the Sun gradually rises from, then sets back into, the horizon.
Furthermore, we mark the times of sunrise, solar noon (when the sun is at its highest elevation in the sky), and sunset, which from my perspective in Des Moines, Iowa in the United States occurred today at 7:18am, 1:22pm, and 7:27pm respectively. Of course, those times are in my local time zone and the time of solar noon from my perspective is also dependent upon my longitude. By contrast, from the perspective of my friends living in London, England in the United Kingdom, sunrise, solar noon, and sunset occurred today at 6:04am, 12:08pm, and 6:13pm respectively relative to their local time zone and longitude.
Real-world alignment is an objective view of data quality, but just as our real world turns, fitness for the purpose of use is a subjective view of data quality that can change as each different user takes their turn using the same data. Therefore, data quality has a rotating frame of reference that can not be ignored. Just as time zones and longitudes were adopted as standards to mark sunrise, solar noon, and sunset relative to the frame of reference of each specific location across the Earth, your organization must adopt data quality standards relative to the frame of reference of each specific business use for data across the enterprise.