This is the first “Measurement Matters,” a column that will show how much measurement matters in achieving and maintaining quality, especially in manufacturing. I will cover topics such as types of measurements and measurement devices, how measurements are made, what can be done with the measurement data, what can influence measurements and the interpretation of measurement data. Some of the topics may be common knowledge to many of you, but I hope there will be something in every issue that will be useful to you, or at least that makes you think. Let’s start with a basic definition. Measuring is the act of quantifying something. That quantification is a measurement. Take this very simple example: You can tell that something is hot or cold—that’s a qualitative assessment of temperature. Such an assessment isn’t a measurement; determining the actual temperature of the item is measurement. Another example is the diameters of golf balls and basketballs. We can tell by looking at them that basketballs are bigger. That’s a crude measurement with nothing more than our eyes. But until we use some kind of measuring tool, we don’t know how much bigger the basketball is—we need to quantify it. Bigger and smaller, hotter and colder, and other such examples are qualitative measurements.

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