During the research, many are faced with the variability of the investigated trait in individual units together, it swings with respect to a certain value, that is, with its variations.That's it, then be sure to take into account to get the most reliable information on the implementation of a scientific study.
Most researchers produce a certain range of variation of the value of a parameter, most often resorted to absolute and relative terms.Among the latter, the most widely coefficient of variation which in case of variable is characterized by a normal distribution, the criterion of homogeneity is combined.This indicator allows you to determine what degree of dispersion will have the values of the test parameters, regardless of the scale and the unit of measurement.
coefficient of variation can be calculated by dividing the standard deviation to the arithmetic mean of the variable value, expressed as a percentage.The result of this calculation may fall in the range from zero to infinity, increasing with increasing variation characteristic.If the value of less than 33.3% - a sign of weak variation.If more - strong.In the latter case, investigated data set is not uniform, its average value is recognized atypical and therefore can not be generalized indicator.Therefore, this combination is to use other indicators.
should be noted that the coefficient of variation is not only characterized by the homogeneity of a population, but also is used as a comparative assessment of her.For example, it is used if you want to compare the size of fluctuations of a particular trait in the population, for which the calculated value of the average values are different.In this case, the scatter of the data does not allow for an objective assessment of acquired values.The coefficient of variation indicates the relative variability of the variable, and therefore may be a relative measure fluctuations in the value of the parameter under study.
However, there are some restrictions.In particular, assess the extent of the variation of the parameter can only be for a particular trait and if the set has a certain structure.This equality of these indicators may indicate both a strong and a weak variation.This is the case, or if the symptoms are different studies conducted in different collections.Such a result is formed by the action of a very objective reasons and that should be taken into consideration during the processing of the experimental data.
The coefficient of variation is widely used in statistical data in various fields of science and technology.In particular, it is actively used in the performance evaluation of the parameters of fluctuations in the economy and sociology.This factor made it impossible to use if you need to assess the variability of the variables that can change its sign.After all, if as a result of payments to be received incorrect values of this index: it is a very small, or it will have a negative sign.In the latter case it is necessary to check the correctness of the calculations.
Thus, we can say that the coefficient of variation - a setting that will allow you to assess the degree of dispersion and relative variability of the mean.The use of this indicator reveals the most significant factors, focus on that will achieve their goals and fulfill the necessary tasks.
