Empirical research methods are factual and exist because of “solid (irrefutable) evidence”. In addition, empirical research methods use the scientific method, unlike other research methodologies. Since empirical research methods are obtained using “solid data”, high internal consistency and stability of measuring instruments is required. In this situation, they (measuring instruments) play the role of the independent and dependent variable that is involved in making a scientific study. Thanks to the internal consistency and standardization of measuring instruments, the stability condition is based, that is, obtaining verifiable results that can be fully trusted. The measuring tool, in turn, cannot be high or fairly reliable if such a tool delivers “raw” and unverified information to make a subsequent analysis. Then, when this requirement is not satisfied, errors creep into the dispersion system, and ambiguous or misleading results are obtained. Empirical research methods depend on an adequate and effective methodology of scientific research, with the help of which reliable and valid data are obtained, which could be easily disseminated to the totality of events, that is, to derive certain laws. However, many theoretical and empirical research methods used to analyze empirical data suggest selections and distributions that are tested according to the experimental condition (group). Empirical research methods, in general, are inevitably associated with the use of accurate measurements, even where it is difficult. For example, they use mainly an observed or perceived pattern of behavior, self-report, and another psychological phenomenon. The main thing is that these measures turn out to be quite accurate. In a nasty situation, theoretical and empirical research methods will have erroneous advantages. When using psychometry, researchers face these important issues:
a) the rudeness of even the most advanced and reliable instrument available for measurement;
b) and also the fact that any psychological measurements are not direct, but indirect.
No psychological properties can be measured directly, it is possible to measure only their alleged manifestations in behavior. Information obtained through measurements is only the observed value of the variables. The “true” meaning always remains unknown. It is possible only to evaluate it, and the error value influences this assessment.
In empirical research methods, there are some variables that affect the experiment: this is the presence of independent variables, dependent variables, and intermediate, or extraneous, variables. The first variables are included in the experimental plan with the help of the researcher; the researcher does not introduce other variables, but they are always in the experiment - and they need control. Variables that are independent are associated with environmental conditions, which can be manipulated during the experiment, or display of these conditions. Variables that are considered dependent are associated with a behavioral result or its display. The essence of the experiment is the variation of environmental conditions and observation of what is happening, the simultaneous control (or elimination of the effect) of the influence of any other (extraneous) variable on them. It is possible to control variables in an experiment using the experimental plan, or using statistical methods.
Thus, the empirical methods of scientific research, thanks to accurate experiments, allow the researcher to draw accurate and irrefutable conclusions on which modern fundamental science is based.