“The data science tools for research of emigration processes in Ukraine”

AUTHORS Andrii Roskladka https://orcid.org/0000-0002-1297-377X http://www.researcherid.com/rid/N-3234-2016 Nataliia Roskladka https://orcid.org/0000-0001-7333-4050 http://www.researcherid.com/rid/N-2596-2016 Anatolii Karpuk https://orcid.org/0000-0003-2920-8131 Andriy Stavytskyy https://orcid.org/0000-0002-5645-6758 http://www.researcherid.com/rid/C-9560-2016 Ganna Kharlamova https://orcid.org/0000-0003-3614-712X http://www.researcherid.com/rid/D-2804-2016


INTRODUCTION
In contemporary conditions of socio-economic relations in Ukraine, the issue of migration is becoming more and more acute. Emigration is one of the most painful issues during the development of independent Ukraine. Each of the waves absorbs a certain part of the young, talented, and promising population of the country. Today's scale of migration is influenced not only by world globalization, but also by the internal situation. For Ukraine, unresolved problems with the labor market, increase in unemployment, low living standards, annexation of the Crimea, and deployment of hostilities in the Donbas region are claimed as the main reasons to push inhabitants out of the state in search of the better life. The latter is a direct catalyst for an increase in the outflow of population from the country -young people and migrant workers. Today, on the European labor market, Ukraine is, as a rule, an exporter of workforce. Usually, highly skilled professionals are migrating, but only a small percentage of them are guaranteed with the employment and appropriate labor standards. Thus, research in the field of migration and its consequences in Ukraine is very relevant, especially for higlighting the prospects of such human loss for the country.
The article aims to analyze the dynamics of external migration depending on the socio-economic situation and to study the prospects of emigration of the Ukrainians using modern tools of business analytics. The structure of the paper is divided into 4 sections: discussing the theoretic background of the issue in the literature review (section 1), analyzing the main tendencies (section 2) and causes of the migration (section 3), particularly in Ukraine, highlighting the methodology in section 4, modeling and forecasting the main migration tendencies (sections 5 and 6), and finalizing with conclusion and discussion.

LITERATURE REVIEW
Hundreds of millions of people leave their homes and travel thousands of kilometers in search of a better life. The migration plays an important role in the development of society and has become a global process that has covered virtually all continents and countries, as well as different strata of the population. A comprehensive numerical analysis of world tourist flows proves that the total number of international migrants is steadily increasing (A. Roskladka, N. Roskladka, Dluhopolskyi, Kharlamova, & Kiziloglu, 2018).
By official definition, "migration" is any, regardless of duration, frequency, and destination, territorial movement from one place of residence to another (State Migration Service of Ukraine, 2019). In 2019, the UN reported that the total number of international migrants in the world is 272 million people, which is approximately 3.5% of the total population. By 2050, the number of international migrants can rise to 405 million people (United Nations, 2019).
According to the State Border Guard Service of Ukraine (2019), today, more than ten million Ukrainians live outside the country, and each year, this number is increasing.
The research of migration processes in Ukraine is a subject of study for many scholars (i.e., Mostovaya & Rakhmanin, 2017; Sociological group "Rating," 2017; Dmytruk & Chudaieva, 2018, etc). Undoubtedly, the main reason for the outflow from Ukraine is the low salary level (Mostovaia & Rakhmanin, 2018). The salary of a Ukrainian is twice less than the average salary in Russia and ten times less than in the developed countries of Europe (Eurostat, 2019). According to the research, Ukrainian migrants are usually well educated and fluent in foreign languages. They call the search for better living conditions the main reason for migration (Dmytruk & Chudaieva, 2018).
The labor migration occupies a special place in the overall emigration flows (Fisher, 2014;Libanova, 2018). Fisher (2014) notes that migration of the workforce is a process of organized or spontaneous displacement of able-bodied population from one country to another within the international labor market for more than a year due to the nature of the development of productive forces and industrial relations, and the effect of economic laws.
It is worth adding that migration is an important part of the national and economic security of the state, influencing the level of trade, production and development of the neighboring countries. During the last years, the technological processes created the conditions for full automatization of production, which led to the so-called Industry 4.0 with a relatively low human presence. Instead, people play an important role in providing services, new technologies, and creative industries (Stavytskyy, Kharlamova, Giedraitis, & Sengul, 2019). Such processes lead to increased inequality in incomes and, therefore, for social aggressiveness. The competence for human capital became a vital issue in the globalization process, stimulating more possibilities for higher incomes for more active part of the population. Beyond doubt, it creates more possibilities for dissimilating new goods, services, trade routes. On the one hand, in the short run, such a situation has to sufficiently increase the developing migration from countries to richer ones. On the other hand, in the long run, it should either equalize the standards of living in the countries or destroy the poorest ones. Stavytskyy et al. (2019) have shown that European countries lean to follow the first scenario and will try to build high-income equally distributed society.
As it was shown earlier, for Ukraine, migration processes play an important and sometimes a crucial role in the state's livelihood. The country has relatively high parameters in human capital, opened borders, which cause mass migration for neighboring countries. Many people work nowadays in Poland, Czech Republic, Slovakia, Germany, Russia, providing the substantial payments (remittances) to Ukrainian relatives. According to the National Bank of Ukraine (2019), the volume of remittances reaches USD 12,2 billion or about 11% of Ukrainian GDP. It is absolutely clear that such value creates not only more possibilities for development, but also some risks for the economy in the case of problems with migrants. Therefore, the outflow of Ukrainians abroad is a crucial problem that needs to be addressed immediately. To make effective management decisions, it is necessary to know the tendency in the number of migrants and to quantify their number for the near future.
The most common indicator characterizing the migration processes is the migration balancethe difference between immigration to the country and emigration beyond its borders. Having a glance at the trends of labor migration, there is a dependence on typical phenomena such as economic cycles, investment flows, employment status, etc. Depending on the duration of the transfer, international labor migration is divided into permanent migration (the exit (entry) of the population to another country for permanent residence), temporary migration (work abroad for a limited time, with the subsequent return to the homeland or moving to another country), seasonal migration (annual migration for the period of a certain season with subsequent return to the homeland), pendulum migration (a permanent job in one country while residing in another, in the presence of necessary international agreements between countries) (Fisher, 2014). The defining criterion that allows migration to be isolated from other movements of citizens across borders is motivation. The motivation is the reason that induces an economic entity to work to achieve a certain goal, the presence of interest in this activity, and how to implement it (Deckers, 2018). It includes such motives: • political (escape from political persecution, racial, national discrimination, etc.); • military (evacuation, re-evacuation, etc.); • economic (job search, higher income, etc.); • social (marriage, recreation, health, etc.); • environmental disasters (mass contamination in one form or another of the environment, droughts, floods, etc.), etc.
Thus, the main reasons for the existence of international labor migration are: a) for the donor country -high population density, mass unemployment, low standard of living and wages, production need (for specialists working in underdeveloped countries); b) for the recipient country -the need for additional labor, mostly highly skilled or inverse -cheap labor (Fisher, 2014 , it is possible to conditionally divide all migration factors into "factors of attraction" and "factors of repulsion," which, in its turn, are conditionally divided into five groups: economic, social, cultural, political and ecological (Table 1).

Low wages
High salary

Polluted environment
Good ecological situation Low-quality drinking water and food Clean drinking water and ecofriendly food The great challenge for Ukraine is that officials are not fully aware of the exact number of Ukrainians who went abroad. V. Voskoboynyk, Chairman of the All-Ukrainian Association of International Employment Companies, claims that there is such a situation that people who go to work abroad are not removed from the state register and are not registered in the recipient state. Therefore, ten million migrants from Ukraine is a completely realistic number (Eurostat, 2019 Since the independence of Ukraine, there have been two waves of labor migration. The first one took place in 2009-2010, when the global economic crisis undermined the financial well-being of Ukrainians. The next wave of migration began after the annexation of the Crimea and hostilities in the Donbas (2015-2016). However, the main factor driving Ukrainians to go abroad (both for earnings and for permanent residence) is the difference in wages. According to a Eurostat report (Eurostat, 2019), the average salary in Ukraine was around €250 in 2018, in Russia -€500, and in the EU, it exceeded €1,500. In particular, in Poland -€750, in the Czech Republic -€870, in Italy -€1,760, in Germany -€2,300, in Ireland -€2,500 ( Figure 1).
The generalized welfare criterion of the population is the so-called "Ranking of happiness," which takes into account not only objective measurement characteristics, but also the level of satisfaction of the population in their country. The components of the happiness index are: • freedom to make life choices; • healthy life expectancy; • perceptions of corruption; • GDP per capita; • social support; • generosity.  So, Poland is the most favorable country for the legal employment of Ukrainian citizens. In particular, the promotion of migration appears in the liberalization of legislation. This was accompanied by the acquisition of a visa-free status, and, therefore, the possibility, firstly, completely legally to be in European countries for three consecutive months, looking for a decent job. In conjunction with the radical simplification of Poland, the procedure for obtaining a so-called working visa by Ukrainians and a lack of a language barrier (at least in oral communication) naturally caused an increase in the flow of labor migrants from Ukraine to Poland. It is necessary to add very active encouragement of the study migration of Ukrainian youth to professional educational institutions of most Eastern European countries -special programs are opened, grants and scholarships are given, special language courses are being prepared (Libanova, 2018).
In assessing the consequences of labor migration for Ukraine, the most important component is the intention to return and its implementation. If the temporary migration has both positive and negative consequences, then leaving Ukraine forever is an almost exclusively negative one. And in this context, it is very optimistic that 65% of potential labor migrants want to return to Ukraine even if they have a permanent job abroad. Undoubtedly, intentions may change, but the opinion of that 23% who would not want to return is also not necessarily implemented. Considering that 41% of Ukrainian labor migrants in 2015-2018 are younger than 35 and only 20% are older than 50, the negative consequences of a large-scale outflow of the economically active population will be inevitable (Libanova, 2018  An average Ukrainian migrant is 32 years old. 72% of them are women, and only 28% are men. 57% of Ukrainians who migrated abroad are employed (18% are employed in the IT sphere), 7% -in job search, and 6% are students.
As it was already mentioned, Russia has the largest number of Ukrainian emigrants -3.3 million. This is evidenced by the study of InterNations (2018). Among European countries, most Ukrainians live in neighboring Poland -about 2 million people, in Canada -1.3 million, slightly more than 1 million -in the United States (InterNations, 2018). Figure 3 shows a list of countries with a population of more than 100,000 in the Ukrainian diaspora.
However, those who return come with new skills, new experience, new work culture -people learn to work at modern enterprises and later can use this experience at home. However, the tendency of returners is that mostly they are seasonal workers and those who go to work for 6-9 months and then go home for several months to relax. Some of them, after several such tours, are thinking of moving their family abroad if there is already a stable job and favorable conditions. A disappointing tendency is observed: the higher the qualifications of an employee, the fewer the chances of his/her return home.

RESEARCH METHODOLOGY
The logic of the research is developed in two directions: to provide some modeling of the process for so-called dashboarding, and to assess the impact of the factors on the process. The toolkit of the first part of the research is the modern tool of data science: the Maple computer algebra system -the world-recognized certified leader in analytical computing and Microsoft Power BI. It is a new line of business in-  telligence development that is a suite of cloud-based business intelligence services for analyzing and visualizing the data (Lynch, 2010; Powell, 2017).
The cubic spline approximation method is used for modeling in the Maple system. The forecast accuracy decreases with an increasing degree of the polynomial function. This drawback can be eliminated by using the segments of low degree polynomials for an approximation that are used for individual parts of the statistical forecasting base. The most effective method of such approximation is spline approximation based on the use of segments of cubic polynomials.
Forecasting in Power BI is based on a method of exponential smoothing for time series prediction. The exponential smoothing method has a good track record in both academia and business and has the advantage that it suppresses noise or unwanted variation that can distort the model, while efficiently capturing the trends.
The second part of the paper is based on the regression analyses for the data of 28 EU states (flows of emigrants) and Ukraine. Any country considers the successful development of the national economy with simultaneous social security for the population. The decisions that are taken by the governing bodies of the countries to manage the economy often have negative consequences, so predicting these effects and choosing the best way to solve a particular situation is the main task of state management. In given this, the role of socio-economic processes forecasting in such a state as Ukraine increases.
The development of the theory and methods of forecasting the socio-economic processes enables the simulation of the future development of certain events by applying new technologies and modern computer technology, which provides the choice of a rational way of management.
The approach is that Maple (Lynch, 2010) and Microsoft Power BI (Powell, 2017) tools are quite effective for forecasting the development of migration processes. The study of interstate migration of the Ukrainian population allowed forming a statistical basis for forecasting, which contains quarterly data on the number of migrants, from 2014 till the first quarter of 2019.
Computer algebra system Maple is a recognized global certified leader in the field of analytical calculations and has in its arsenal powerful prediction tools, including methods of extrapolation splines. Given the lack of monotony in changing the number of migrants, the most promising method of forecasting is the extrapolation of splines (Yemets & Roskladka, 1999). Splines allow representing a complex functional dependence in the form of a set of cubic polynomials that are smoothly interconnected. In order to implement the method of spline extrapolation, the Maple system contains Spline function, which is part of the CurveFitting library ( Figure 4).
A cubic spline is a spline constructed of piecewise third-order polynomials which pass through a set of m control points. The second derivative of each polynomial is commonly set to zero at the endpoints since this provides a boundary condition that completes the system of m-2 equations. This produces a so-called "natural" cubic spline and leads to a simple tridiagonal system, which can be solved easily to give the coefficients of the polynomials.
The spline function in the Maple system has the form following: ,; As this method does not use a single polynomial of the degree n to fit all 1 n + points at once, it avoids high degree polynomials and thereby the potential problem of overfitting. These low-degree polynomials need to be such that the spline ( ) Sx they form is not only continuous, but also smooth.
So, Figure 5 is a graphical interpretation of the resulting cubic spline along with a set of points that form the statistical basis for forecasting. The implementation of the splines extrapolation method in the Maple system gave the forecast of the value of 2520 emigrants from Ukraine in 2019.
Microsoft Power BI analytics platform is a new direction for business intelligence development, which is a set of cloud-based business analytics solutions for analyzing and visualizing the data that includes the prediction function.
When creating a forecast, the additional input parameters are specified, such as the length of the forecast, the confidence interval, and so on. The main advantage of the Power BI analytical platform is the super-powerful means of visualizing analytical reports (Figure 6).
By the results of forecasting, with the help of the Microsoft Power BI analytical platform, the predicted value of 2,444 emigrants was obtained by the end of 2019. A tendency for an increase in the number of migrants in 2019 compared to 2018 is observed. It should be noted that the projected value of the number of emigrants is the largest over the last four years, which may be well indicative as a new third wave of migration processes.   Table 2).
The most appropriate regression model to highlight this dependence is the following: If to have a look on the internal factors that push people to migrate in Ukraine, the correlation analysis provided the result that the poverty (P) is the main reason for the emigration from Ukraine (Table 3), while the crime (CR), the level of health security (IL), the real wages (RW), and the level of trust in the government (SG) were detected as nonsignificant. However, these factors were claimed as significant in the vast amount of scientific papers (i.e., Kharlamova & Sitnitskiy, 2016;Bilan, 2014, etc.).

СONCLUSION
Motives, causes of emigration processes and their interrelation with the economic environment in Ukraine are analyzed; the features and factors of the influence of external labor migration on the economy of the countries-adopters of migration processes are revealed; the negative and positive effects of emigration on the socio-economic situation in Ukraine was assessed; the number of Ukrainian emigrants and their migratory sentiment were analyzed; the variant forecast for the migration of population of Ukraine for 2019 has been developed based on the Maple computer algebra system and the Microsoft Power BI analytical platform. This may lead to the development of an information system for emigration, migration, and immigration forecasting in the future.
The migration movement of the population is an integral part of the process of globalization, and then further, the scale of external migration will grow, more and more people will live outside the country of  origin and throughout the life will change the country of residence more than once. Changing the priorities for potential migrants, in particular, the reorientation of a significant part of them from Russia to European countries, is not coincidental and of a permanent nature.
The main motive for the departure of most Ukrainians is undoubtedly the hope of receiving significantly higher wages, and the evidence of the received model supports it. But economic factors are not the only catalysts of migration processes. More and more migrants are paying attention to social security, level of corruption, and other parameters that form the "Ranking of happiness." Therefore, raising wages to the level comparable to the neighboring countries will undoubtedly reduce the extent of the spread of migratory sentiment, but will not completely eliminate it.
At the same time, the inflow of financial capitals from migrants, new investments, the expansion of the economic influence of the European Union can lead to the modernization of Ukrainian enterprises, providing new technologies and, therefore, to demand a new type of workers, who can support innovations. It could be the catalyst for the dramatic increase in salaries that happened during the last years. This process can significantly decrease the number of people desiring to leave Ukraine. This consequence started a new approach to changing the Ukrainian mentality. If many years the dominant philosophy of Ukrainian people was "my house is off the edge," which led to hiding incomes, avoiding paying taxes, weak maintenance of infrastructure, then nowadays more and more people unite to realize some infrastructure projects for themselves, which improves their life quality. Such an approach definitely decreases the level of migration. The other issue that also stimulates a decrease of emigration lies in the fact that many people who could not find themselves in Europe returned and decided to build their life in Ukraine. It leads to more political responsibility of citizens, which also should make Ukrainian people happier.
The construction of the proposed migration modeling system is aimed at creating an instrument for the study of migratory movements of the population. With the help of the modern tools of business analytics based on the input information, conclusions are drawn about the readiness of a person to emigrate. The results of implementation of the migration process modeling system in the activities of the governing bodies should be aimed at simplifing the processes of assessing the migration status of the population. Combining this knowledge with the information on the number of people allows assessing the potential migration situation.