What is a scale? This is such a sign system for which the display is specified. The scale element is assigned to real objects. We can say that the measurement scale is a graduated ruler, on which the values of any quantity (distance, temperature, pressure) are plotted. The problem associated with ensuring high quality products is inextricably linked to the quality of measurements. If the latter does not meet the modern requirements of technical progress, there is no way to achieve the appropriate product quality. Next, we will talk in detail about what the measurement scale is for. The types of measurement scales will also be discussed in detail in this article.
Measurement and product quality
As mentioned earlier, if you successfully solve issues related to the accuracy of measuring the quality parameters of materials and other products, as well as maintaining modes in production technology, product quality will improve significantly. If aTo put it simply, quality control is the measurement of all parameters of technological processes. The results of their measurements are needed to control the process. The more accurate the results, the better the control.
Measurement state has the following main properties:
- Reproducibility of measurement results.
- Accuracy.
- Convergence.
- Receiving speed.
- Uniformity of measurements.
Reproducibility of results is the closeness of measurement results of the same value, which were obtained in different places, using different methods and means, at different times and by different people, but under the same conditions (humidity, pressure, temperature).
The convergence of measurement results is when the results of measurements of the same quantity, which were repeated using the same means, the same method, in the same conditions, with the same care, are close.
Any measurement is carried out using the appropriate scales.
Measurement scale. Types of measurement scales. Examples
It has already been said that a scale means a series of certain marks that are ordered. This series corresponds to the ratio of successive values of the measured value.
What is the measurement scale? This is a sequence of values of quantities that have a different size and are of the same name. It must be accepted by agreement.
In practice, five types of scales are used:
- Order scale.
- Relationship scale.
- Name scale.
- Interval scale.
- Scale of absolute values.
Order scale
The places that values occupy in such a scale are called ranks. The scale itself is also called rank or non-metric. In it, all numbers are ordered by their places. The intervals between them cannot be accurately measured. This scale makes it possible not only to establish equality or inequality between the measured objects, but also to determine the nature of inequality in the form of logical judgments such as "more and less", "worse and better".
With the help of the scale of order, it is possible to measure indicators that are qualitative, but do not have strict quantitative measures. Such scales are widely used in psychology and pedagogy, as well as sociology.
Relationship Scale
It differs from the interval scale by a strict definition of the position of the zero point. For this reason, it does not limit the mathematical apparatus used in processing the results.
What is the relationship scale? It measures the quantities formed as the difference of numbers, which are counted on a scale of intervals. Thus, calendar time is counted according to the interval time, and time intervals - according to the ratio scale.
When using this type, the measurement of any quantity is an experimental determination of the ratio of this same quantity to a similar one, which is taken as a unit. When measuring the length of an object, you canfind out how many times it is longer than the length of another object, which is taken as a unit of length, for example, a meter ruler. If only ratio scales are used, then the measurement can be given a more particular, narrow definition: the measurement of any quantity is the empirical finding of its relationship to the corresponding unit.
Name scale
This scale is also called nominal. She is the simplest. The numbers in it play the role of labels. They are needed in order to detect and distinguish the studied objects. The numbers that make up this scale are allowed to be interchanged. There is no less-more relationship in it. For this reason, some people think that its application should not be mistaken for a measurement. Using the naming scale, only a small number of mathematical operations can be performed. For example, you cannot subtract and add its numbers, but you can count how many times a certain number occurs.
Interval scale
This is a type in which the numbers are not just ordered by rank, but also separated by certain intervals. The zero point in this scale is chosen arbitrarily. This distinguishes it from the relationship scale. Examples include calendar time (in various calendars, the beginning of the calculation of years was set for some random reason), the potential of the electric field, temperature, and the potential energy of the lifted load.
The results obtained by measuring on this scale can be processed by any mathematical method, except for determining the ratios. The data that the scale shows answer the question onhow much less or more?”, but they do not make it possible to affirmatively say that one of the values of the investigated quantity is several times less or more than the other. For example, if the temperature in a room has risen from 10 degrees to 20, it cannot be said that it is now twice as warm.
Scale of absolute values
Often the magnitude of something is measured directly. For example, they directly count the number of defects in products, the number of units of manufactured products, the number of students present at the lecture, how many years have lived, and so on. By making such measurements, the exact absolute quantitative values of what is being measured are noted on the scale. The absolute value scale has exactly the same properties as the ratio scale. The only difference is that those values that are indicated on the first one are absolute, not relative.
The results obtained after measurement on this scale are the most reliable and informative. They are very sensitive to measurement inaccuracies.
Conclusion
Thus, it became clear what the measurement scale is and what it is used for. As it turned out, she was not alone. There are five of them, and each is used to measure certain quantities. If earlier it seemed that the scale should measure only physical quantities, then it turns out that such sciences as psychology and sociology also have their own scales that measure numerical indicators. In fact, a psychological test toois such a scale.
The measured quantity is called a variable, and what is measured is called a tool. As a result, data or results are obtained, which can be of different quality and refer to one of the scales. Each of them places restrictions on the use of some mathematical operations.
