How chill is vanilla ice-cream to strawberry – while one can feel the difference in chillness and measure the degree of cold – there are things which are better measured by feeling and not by scale.In our school days, it was all about mathematical tables, and the one who could reel off 13 table was a wizard ! ~ do you know what is ‘mother cow index’ ?
Qualitative scales prove their usefulness time and again. Without them, we would struggle to conceptualise ideas of pain (a doctor might ask a patient to rank his symptoms) or grade the severity of weather conditions (like the Beaufort Scale does).Date, when measured from an arbitrary epoch such as BC or AD, helps us understand time, while direction measured in degrees from true or magnetic north orients us in physical space.Quantitative scales are much easier to evaluate, since they are effectively comparisons to a known standard. A square-kilometre, a teaspoon of sugar or an hour-long lecture are basically unchanging measurements. Qualitative scales are more subjective. Neither quantitative nor qualitative scales, however, are ever 100% accurate: they are each limited by the uncertainty baked into the definitions of units themselves.Any true measurement, when you get down to it, is arbitrary. Yet the very human urge to appraise, quantify, and compare persists, and so we continuously seek new ways to describe our experience of the world. In 1805, Rear Admiral Sir Francis Beaufort, an Irish hydrographer in the Royal Navy, wanted a way to more accurately measure ocean breezes. Each day aboard the HMS Woolwich, he recorded in his diary wind force and sea conditions, from eerie calm to violent gales. Today, a “Beaufort 0” means an ocean as smooth as glass, while a "Beaufort 12" indicates crashing waves, hurricane-force wind, whitecaps and greatly reduced visibility. By and large, qualitative scales fall into one of two categories: Ordinal measurements (in which values can be arranged in a meaningful order), or Interval measurements (in which values can be arranged in a meaningful order, and the difference between two values matters). For example, an earthquake that measures 6.0 on the Richter scale is many orders of magnitude greater than a small trembler of 3.0. So the order of quake size matters, and the interval is also fixed, meaning that Richter’s scale is an Interval scale.An “extremely satisfied” response on a customer service ranking is not triple the satisfaction of “somewhat dissatisfied”; even the difference between 10C and 20C, while quantitative, is not an intuitive measurement. Some argue that these limitations make qualitative scales inherently less functional. Indeed, while proper measurement ascribes value to the physical world, our perception of the physical world varies widely. “There are things that we can measure and things we can’t,” says Andrew Hanson, senior research scientist at the National Physical Laboratory (NPL) in the UK. “But even what we canmeasure, we can only do to a degree.”Hanson works in soft metrology: he studies measurements that relate to sensory scales like color and light, which are quantitative but also subjective. No human can see ultraviolet or infrared light, but even shades on the visible spectrum appear differently from person to person – a difference that has real-world implications. Think about traffic signals, which must appear red, amber, or green. The way we perceive the brightness of these coloured lights is non-linear: numerical changes in input (watts) don’t always translate to the naked eye, or to human experience.“For a scale to become legitimate, everyone must agree on its units and intervals,” Hanson explains. Despite the fact that they aren’t always linear or mathematical, qualitative scales still seem to get the international greenlight.Take the Scoville scale. Named after its creator, American pharmacist Wilber Scoville, this scale ranks chili pepper spiciness. But the Scoville doesn’t actually measure the amount of spice, or capsaicin, in a pepper; rather, it notes the number of dilutions needed to put out a capsaicin-fuelled fire.At present, qualitative measurements help us translate ideas that are almost poetically incalculable: the length of a city block or the Grand Canyon, the pitch of a teakettle or a lightning strike or a whisper in the dark. Sounds complicated but true With regards – S. Sampathkumar 28th July 2018 Inspired by BBC article and largely reproduced from : http://www.bbc.com/future/story/20180726-the-measures-that-dont-need-maths PS:For farmers, the literal size of a field was much less important than its utility in sustaining cattle. Ireland once used "a cow's grass" as a unit of measurement — that is, the amount of land needed for one cow. In America, the "mother cow index" determined how many pregnant cows an acre of land could support. As opposed to size, it was a quality measurement.