Vol. 26 No. 1 (2024)
Articles
Abstract: The research aimed to analyze the impact of fiscal policy and its impact on some indicators of sustainable development for the period from (2004-2021), as fiscal policy is one of the components of the general economic policy used by the state, and it exercises its work by controlling the size of the money supply and changing it according to what is appropriate and appropriate to the conditions. Economic development in the country, and the issue of sustainable development is one of the issues that has emerged as a result of the abusive use of the environment in the recent period as a result of the accelerating pace of economic development processes in countries of the world, especially developing countries, which has led to To a large depletion of resources and large pollution operations that caused damage to the environment, the standard analysis method was used for the purpose of demonstrating the impact of financial policy on some indicators of sustainable development, through the use of the program ( Eviews13 ) and drawing diagrams. The program was relied upon. ( Amos Graphics ), the study came out with important conclusions, including that there is variation in the effects of financial policy on some indicators of sustainable development, as some were positive and others were negative.
Abstract: The main purpose of this study is to use the Keda model to predict financial failure, in order to achieve the objective of the study, the Iraq Stock Exchange was chosen as an applied sample, and the study methodology depends on identifying a major problem that has been clarified through several questions centered on an important question, is it possible to use the Keida model to predict financial failure?, The study sample was also reflected in the sectors of the Iraq Stock Exchange. The banking sector by (6) banks, As the period of the study of companies was limited between (2017-2022), which indicates that the study period was five years, and in order to extract the results in light of the data withdrawn from the Iraq Stock Exchange study sample, the study resorted to using a set of important indicators in financial, administrative, and statistical analysis according to the (SPSS) program. V.23 & Excel.v.2010), Accordingly, the study reached a set of results, perhaps the most prominent of which represents a better diversity in the investment portfolio can be achieved by building a diversified portfolio of ordinary shares that belong to different sectors and have different risks and benefits, and the study also recommends that care must be taken to achieve the appropriate balance between investment risks and expected returns to achieve the best financial performance of the investment portfolio.
Abstract: Many developed and developing countries, including Iraq, suffer from the problem of non-distribution of income and wealth, as it is still visible and deepens continuously with the succession of different time periods, and the era of globalization has a negative impact on the difference in expanding incomes, which is reflected in family incomes and how this income is distributed. Interest began to study the measurement of income inequality by economists after World War II, with the aim of drawing economic policy and drawing the general direction of growth of the national economy in the medium and long term, Due to the widening gap between different income groups, there are two classes, a lower category, and a category as a result of several factors, including inflation and financial corruption. Therefore, the need came to analyze and measure the distribution of income in the governorates, and the aim of the research was to measure the disparity in the distribution of income through the graphic presentation of the Lorenz curve, as well as the use of statistical measures represented by the Gini coefficient and the use of cumulative ratios of income and expenditure for the Iraqi governorates for the year 2014, and it was found that the distribution of income according to the Gini index for the governorates shows the depth of disparity in spending at the household level and its reflection on the distribution of income as well as its social effects.
Abstract: Credit activity is the backbone of banks, so it is important to analyze and study credit risks in order to hedge against possible losses as they affect the future performance of banks, and in this research we will use the International Financial Reporting Standard IFRS9 in measuring potential credit risks by applying the expected losses model (ECL (contained within IFRS9 according to scientific foundations).the research problem was represented in the questions(Does banks adoption of the expected loss model contained in IFRS9 in treating realized losses lead to misleading the financial statements? Does applying the expected loss model contained in IFRS9 affect the quality bank profits according to their total assets?The research aimed to present the requirements of the International Financial Reporting Standard IFRS9, as well as to indicate the extent to which private Iraqi banks, the research sample (Iraqi Trade Bank ) adhere to the requirements of the content of the International Financial Reporting Standard IFRS9.In light of this, the research reached a set of conclusions, the most prominent of which is the need to apply the International Financial Reporting Standard IFRS9 financial instruments in the banks selected as the research sample, as well as the presence of great challenges facing banks in particular and economic units in general with regard to the substantial increases in credit risks with regard to the initial recognition of the application of expected credit losses According to the IFRS 9 standard, and that the application of the International Financial Reporting Standard IFRS9 achieves an increase in loan loss provisions that result in more useful provisions, especially when credit conditions deteriorate.While the most important recommendations were that banks should develop plans and procedures to face problems by applying expected credit losses according to IFRS 9 standard with regard to unstable economic conditions, especially those related to deflation and inflation, as there will be differences between provisions and depreciation of money and within international financial reporting standards, to In addition to the importance of setting a unified ratio for the provision for loan losses for the purpose of narrowing the gap in front of accounting policies that ultimately lead to a decrease in the quality of profits and moving away from managing profits
Abstract: The worldwide financial crises have prompted inquiries on the caliber and extent of independent audits. As a response to the prevailing circumstances faced by numerous private banks, including bottlenecks and bankruptcies, and in line with the Central Bank of Iraq's objective to enhance the efficacy of external auditing, the Central Bank mandated the joint audit approach for the examination of private bank accounts pertaining to the fiscal year's final financial statements. The current year is 2016. The primary objective of the present study is to examine the impact of altering the acceptance of joint audit on the relationship between audits quality and earnings management in banks that are listed on the Iraqi Stock Exchange Organization. The research utilized a statistical population consisting of all 44 banks that were admitted to the Iraqi Stock Exchange. From this population, a sample of 15 banks that applied for joint audit was selected for the purposes of this study. The initial hypothesis test findings indicate a lack of statistical significance in the association between earnings management and audit quality. However, when considering the independent variable of auditor expertise as a metric for assessing audit quality, a positive and statistically significant relationship between earnings managementand audit quality is observed. The findings from the second hypothesis test of the study indicate that there is no evidence to support the notion that joint audit plays a moderating effect in the association between audit quality and profit management.
Abstract: The main objective of the research is to identify the extent of the impact of these mechanisms of corporate governance on the effectiveness and efficiency of the internal control system, and this research was conducted on a sample of 12 companies for the period from 2017 to 2021. It was concluded that the application of governance mechanisms helps to increase and improve the effectiveness of the internal control system as a tool for the provisions of control and control over all uncontrolled behaviors, and the absence of legislation or legal text in Iraq directly concerned with governance, or its principles, or Its mechanisms, except for some paragraphs that overlap within other laws that regulate the work of companies, and that the size of the board of directors of all banks and in most of the research years was within the scope (determined in accordance with Article (104) of the amended Companies Law, which ranged from (5) to (9). Members, The banks varied in the concentration of ownership rates, as they reached the highest percentage during the research period with an arithmetic mean (94.00%). Islamic lowest percentage with the arithmetic mean (of 43.67%), and the sample banks varied in their results as Related to the percentages of administrative ownership, as the Kurdistan Bank obtained the highest arithmetic mean of (87%), while Al-Thiqa Investment Bank came in last place
Abstract: In achieving its objectives, this study relied on the analysis of time series through the use of appropriate standard methods, as the results showed that the time series under study are unstable in their levels, but they are stable when taking the first differences for them using unit root tests, as the results of the model test showed ( ARDL): the existence of a long-term equilibrium relationship between the balance of payments and the value of the Iraqi local currency.
Abstract: Our study aims to explore the role of paradoxical leadership behaviors in enhancing strategic agility of organizations. The study attempts to provide an integrated theoretical framework for the most important issues proposed by writers and researchers regarding the variables of the study, in addition to a practical analytical framework for the opinions of a number of department heads and teaching staff in (17) private colleges and universities in the middle Euphrates region in Iraq. The study sample included (133)departments heads, and (218) teaching staff in those colleges.Our paper used the questionnaire as a tool to collect data, and a number of statistical methods were used to analyze data with the help of (Smart PLS)program. The study reached the validity of the hypothesis regarding the effect of paradoxical leadership behaviors on strategic agility . The study introduced a number of recommendations related to its topic, including the necessity of adopting a set of paradoxical behaviors by leaders to enhance strategic agility in private universities and colleges.
Abstract: In this paper, we will employ one of the factors reduction methods SCAD with the regression model of factorial experiments with two levels of degree〖 2〗^4, as this method was compared with previous methods, and the MSE criterion was employed to compare the methods, as simulation methods and real data showed that the proposed method had its results better .
Abstract: One of the most prevalent illnesses in today's world is viral hepatitis, and there are several mathematicalmethods to determine the most important factors that lead to the infection with this disease. In this paper, the MCPmethod is used to select the most important factors ( variables ) that lead to this injury, where simulation is used tocompare this method with some penalty methods (lasso, adaptive lasso and MCP). Using the MSE (mean squareerror) and was applied to the real data.
Abstract: This study aims to illustrate the influence of green production dimensions on the attainment of sustainable development, to enhance the efficiency of industrial entities. This trend is deemed essential in safeguarding the environment against pollution and waste generated by manufacturing procedures, particularly in light of technological advancements and the obstacles encountered by these organizations in implementing significant modifications and use them As an effective means towards obtaining environmentally friendly products, The problem of the study is what is the relationship between the green production dimensions and sustainable development and the impact that it can have on it. The significance of this study lies in its emphasis on encouraging factory management to remain abreast of environmental shifts by devising innovative measures to minimize waste and emissions stemming from production procedures, while also engaging in waste recycling, and avoiding material waste and excessive energy consumption. In order to attain the study's objectives, a 32-item questionnaire was utilized. The study sample consisted of 60 participants who were selected from different departments of the Diwaniyah tires factory. Two primary hypotheses were formulated in accordance with the aim of the investigation. To scrutinize the outcomes and validate the conjectures, a series of statistical techniques were employed utilizing the statistical software (SPSS.vr.26) and (AMOS.vr.26). The study's findings indicate a significant correlation and causal relationship between the dimensions of green production and sustainable development. The factory's application of the dimensions of green production will be sufficient to reduce the pollution rate in pursuit of sustainable development, and enable it to be innovative in product development processes in a way that enhances environmental, social and financial performance at the same time, as well as attracting new customers.
Abstract: The formulas of contemporary international economic relations take two traditional forms, which are represented by the movement of international trade, in both its commodity and service parts, while the modern one is embodied in the movements of capital and people internationally, the importance of research is concentrated in the extent of the ability of the state's government programs to deepen its economic relations with its regional and international surroundings. In order to clarify the formulas and indicators of contemporary international economic relations, the research was divided into three sections, the first dealt with international trade in goods and services; and the second section dealt with the movement of capital internationally and direct foreign investments by reviewing relevant data, and the third topic dealt with the movement of people internationally. The study came out with a set of conclusions and recommendations.Among the most prominent conclusions that came in agreement with the validity of the research hypothesis, is that the historical legacy of the developed countries made them impose, in many cases, the formulas of contemporary international economic relations.
Abstract: The research aims to address the concept of fair value accounting according to International Financial Reporting Standard No. (13) with regard to accounting measurement and disclosure. And the principle of historical cost refers to events that took place in previous periods far from reality, so the information is old and shady, and specialists in the accounting profession had to find suitable alternatives to keep pace with the development and change in the economic conditions accompanying the contemporary business environment, so this research came to clarify the role of measurement Accounting disclosure according to the fair value principle improves the quality of financial reporting, and thus influences the administrative decision-making process. The research was applied in three banks listed in the Iraq Stock Exchange, which are the Middle East Investment Bank, the Khaleeji Commercial Bank and the Commercial Bank of Iraq for the years (20117-2021), where the profit multiplier model was used for the period (2017-2021) to measure the fair value of the shares of these banks, then The quality of financial reporting was measured using the (Chen, 2016) model, as the nature of the correlation and impact relationship between fair value accounting and the quality of financial reporting for these banks was determined during this period. The research reached a set of conclusions, the most important of which was that the importance of fair value accounting emerged through the changes that would make the financial statements more useful and transparent about the financial situation in the business environment as well as enhancing confidence through the presentation and accounting disclosure of the financial statements, as the financial reporting aims to Providing useful information to current and prospective users to assist them in making their various operational and strategic decisions, as well as helping to provide the necessary information for estimating future operational, investment and financing cash flows. Measuring and disclosing fair value can help improve the quality of financial reporting by providing appropriate information. And reliable can help meet the needs of users of accounting information .
Abstract: The research aims to explain the effect between the independent variable of destructive leadership, represented by its dimensions (administrative ineffectiveness, harshness of personal relationships, laissez-faire management, hesitation/retirement from work), and the dependent variable (administrative decisions). The research followed a descriptive and analytical method, and the researchers used the questionnaire as the main tool for collecting data, by selecting a random sample size of (120) respondents, With the aim of presenting and analyzing the responses of the sample members and their perceptions of the study variables and their sub-dimensions, and testing the research hypotheses using descriptive and inferential statistics methods, as well as using personal interviews and field observations as tools to assist in collecting data, statistical programs were used. One of the most important results is the necessity of working to confront and limit the spread of work behaviors this is destructive in making the right administrative decisions that are the basis for shaping the future of the company under study. One of the most important recommendations is to completely prevent the employment of employees with destructive characteristics. However, it is also important to detect problems early and intervene to reduce their harmful effects, this means discovering destructive behaviors early in the person’s entry into work and reducing their impact, this may include providing some education and guidance regarding toxic behaviors during the first weeks of work, as well as early detection through use behavioral assessments.
Abstract: This research aims to know the role that evidence-based human resources management practices play in promoting green behaviors of employees. To achieve the research objectives, the relationship and influence between the dimensions of evidence-based human resources management practices (leadership, motivation, organizational processes, team dynamics, Turnover rate, satisfaction, training, and performance evaluation) in the dimensions of employees’ green behaviors (sustainable work, conservation behaviors, avoiding harm, influencing others, taking initiative). The methodology dealt with a group of paragraphs, the most important of which is the research problem, the content of which is that there have been increasing interests and developments recently in the sustainable human resources system. In light of this, a hypothetical diagram was built that embodies the relationship between the variables in question, and a set of main and sub-hypotheses emerged from it. In order to achieve the aforementioned research goal and answer the research questions and test the validity of its hypotheses, the study relied mainly on (the questionnaire), which is the main tool for collecting data and information, and by adopting the descriptive approach. Because of that, a random sample was chosen, representing the research community working in the Kufa Cement Factory in the Kufa Governorate. Al-Najaf Al-Ashraf, (300) questionnaires were actually distributed, and the valid questionnaires for analysis were (279) questionnaires after excluding the invalid and abnormal questionnaires. After evaluating and testing the credibility and stability of the research measurement tools, data analysis and hypotheses testing were conducted using advanced statistical tools and analysis using statistical programs (SPSS. Ver. 26.) and (AMOS. V. 25). Several conclusions were revealed, the most important of which is the presence of a statistically significant effect between... Between evidence-based human resource management practices and employees’ green behaviors, this explains that increased interest in evidence-based human resources management practices leads to enhancing employees’ green behaviors. The study recommended several recommendations, the most important of which is urging the management of the Kufa Cement Plant to pay attention to employee participation, as it has a role in promoting green behaviors for employees by providing a safe and comfortable work environment that allows them to express their opinions and suggestions and listen to their problems.
Abstract: The study aims primarily to determine the impact of content marketing on customer response from the point of view of Al-Qadisiyah University employees, based on a main problem diagnosed with several questions: To what extent is there awareness of the relationship of influence and connection between content marketing on customer response?Content marketing was adopted as an independent variable through its four dimensions represented by (relevance, credibility, attractiveness, value), while customer response was expressed as a dependent variable through its two dimensions represented by (word spoken, and intention to convert).The questionnaire form was adopted as a main tool for collecting data related to the variables of the study, as the spatial boundaries of the study were (selected colleges from Al-Qadisiyah University), while the study sample was represented by (employees of Al-Qadisiyah University), and the sample size was289), and the statistical program (SPSS.V.29) and the program (24.Amos.V) were used to test the hypotheses. The results reached by the study showed the existence of an influence and correlation relationship between the variables of the study, and the study came out with a set of recommendations.
Abstract: These crops suffer from fluctuations in production quantities, cultivated areas, and average yield productivity during the period (2004-2021). The analytical descriptive method and the standard method for measuring production volume and estimating the production functions of strategic summer agricultural crops in Iraq for the period (2004-2021) and future predictions for the volume of production of those crops, as this research dealt with two axes, the first axis included the reality of the production of strategic summer agricultural crops in Iraq and the factors influencing them for the period (2004-2021), while the second axis dealt with estimating and measuring the functions of producing summer strategic agricultural crops in Iraq for the period (2004-2021) and its future forecasts for the period (2022-2023), By using the standard model (Eveiws12) for a set of tests, during which the researcher dealt with a quarterly series of (24) observations, based on official data and statistics issued by the relevant ministries, where he used a set of standard methods and was the most important. The stability test (Extended Dickey-Fuller test, Phillips-Peron test), the cointegration test of the error correction model, and the autoregressive distributed delay (ARDL) model test. Therefore, the results of this axis were the existence of a relationship between the production quantities of strategic summer agricultural crops and the variables affecting them, As for future predictions, the study showed that the quantities of rice production are trending downward, while the yellow corn crop is trending towards an increase, which necessitated focusing on recommendations, the most important of which are: If we want to increase the volume of crop production, we have to control and control these factors now and in the future, as well as state support for farms. From providing agricultural production requirements and manufacturing them locally and preventing their import from abroad, and using modern and advanced methods of agricultural machinery and equipment, which would raise the production of summer strategic agricultural crops.
Abstract: Foreign investment is of great importance in advancing economic development in any country, as it is considered one of the basic economic activities for achieving economic growth, as it plays a role in the process of bridging the emerging financing gap between domestic savings and the necessary investment needs. The economies of the world in general and the Iraqi economy in particular and the advancement of economic sectors dependent mainly on one resource and neglecting the rest of the sectors, by providing a suitable environment to attract foreign investments, and the research problem comes that Iraq's investment environment suffers from instability as an environment that repels foreign investments. The research indicated that The methodology is: the ineffectiveness of foreign investment in Iraq and the low ability of those investments to raise the level of economic sectors and reduce the effects of inflation, the employment of manpower, and the introduction of modern technologies. The Iraqi inflation rate for the period (2004-2021) by adopting the case study method, which is the ideal method in the to study this type of investment. The research concluded that foreign investment is of great importance in advancing the development wheel in any country, as it is considered one of the basic economic activities in achieving economic growth, and plays a role in bridging the financing gap arising from the domestic savings house and the necessary investment needs. The research recommended the need to work on optimal utilization of foreign investments by drawing future plans in order to advance the reality of the activities of the economic sectors and achieve economic growth.
Abstract: The current study aims to know the strategic renewal and its impact on organizational brilliance according to the opinions of a sample of workers in private banks in the provinces of Diwaniyah and Babel in the Middle Euphrates region in Iraq. To determine the importance of the study and the nature and level of interest in the banking sector in the study sample, the questionnaire form was adopted as a main tool for all data related to the field side of the study (135) questionnaires were distributed, and after sorting and verifying the data, the number of questionnaires suitable for analysis reached (124), with a response rate of (92%). The strategic renewal variable includes two dimensions: (exploratory strategic renewal exploitative strategic renewal), While the organizational brilliance variable includes three dimensions: (leadership brilliance, service and innovation brilliance, and knowledge brilliance). The current study sought to choose a number of main and sub-hypotheses related to correlations and influence relationships between the study variables. In order to answer the questions related to the problem of the study and reach the set goals, and in order to process the data, the study used many statistical methods, the most important of which are (normal distribution, arithmetic mean, exploratory and confirmatory factor analysis, and structural equation modeling) using the statistical program SPSS.25, the Smartpls program, and the Amos v.23 program, Cronbach alpha. The results of the study showed a direct effect of strategic renewal on organizational brilliance.
Abstract: The current study aims to explore the relationship between the moderating influence of auditors' psychological characteristics, particularly narcissism, and the financial expertise of the board of directors on the auditors' expectations gap. This investigation delves into whether the financial expertise of the board of directors impacts the auditors' expectaions gap. To achieve this objective, a questionnaire was employed to test the hypotheses. The research hypotheses were assessed using a sample of 246 auditors and managers from small and medium-sized companies in Iraq, utilizing PLS software. The results revealed a positive and significant relationship between the CEO's narcissism and the auditors' expectation gap. Additionally, there was a negative and significant relationship between the financial expertise of the board of directors and the auditors' expectation gap. Furthermore, the auditor's psychological characteristics were found to moderate the impact of the financial expertise of the board of directors on the auditors' expectation gap. Notably, this moderation did not influence the relationship between the CEO's narcissism and the auditors' expectation gap. A comprehensive review of existing literature indicated a dearth of research on the role of auditors' psychological characteristics as moderators due to the narcissism and financial expertise of the board of directors on the auditors' expectations gap, particularly in emerging markets. Consequently, this study contributes to filling this research gap, offering valuable insights into the dynamics of auditors' expectations in emerging markets and advancing scientific knowledge in this domain.
Abstract: The research aims to highlight the role of Islamic banks in investment projects and their relationship to social and economic development. Islamic banks, which carry out their work and activities in accordance with Islamic law and have an effective role in the investment process, face many problems. Islamic banks face many problems, including the unsuitability of the environment, the lack of researchers and scholars interested in it, and the lack of a culture in them. just as the Central Bank deals equally with all Islamic banks and needs support and assistance, the alternative hypothesis confirms the existence of a correlation between the importance of Islamic banks and investment. The research also used a number of statistical methods, arithmetic means and standard deviation, and the research used the SPSS program for the purpose of demonstrating the impact of Islamic banks on investment. The researcher created the regression model used and the t-test values and their significance. The study reached a set of conclusions, the most important of which is that there is a positive, morally significant relationship between the importance of Islamic banks and investment, and that any increase or decrease in the importance of Islamic banks leads to an increase or decrease in investment. We reached a number of recommendations on the necessity of raising the capabilities and capacities of banking tools in Iraqi Islamic banks at all administrative and operational levels to advance the reality of financial and banking services.
Abstract: The study aims, to use the run test method, to evaluate the efficiency of the. Iraqi stock market at a weak level. The study community represents, the industrial sector of, the Iraqi stock market, and the study sample. consisted of 5 companies for two years, monthly from 1/1/2021 to 31/12/2022. The closing prices of stocks and stock, returns for banks were used, as a research sample in the Run test.The study found that the Iraqi ,stock market is efficient .at a weak level, represented ,by the research sample companies, as well as the efficiency of each. company that was researched, at a weak level. This indicates that investors cannot achieve, abnormal returns, in addition to the presence ,of a random walk in the monthly returns series .for banks and research, sample companies.The study recommended providing, complete information for companies ,listed on the stock market, responding quickly to this information, ensuring transparency. in financial transactions, as well as developing and employing, experts and improving the performance ,of companies and the economic environment.
Abstract: The study aimed to measure the spiritual marketing variable as an independent variable with its dimensions (faith, morality, realism, and humanity) consisting of (16) items, and its effect on purchase intention as a unidimensional dependent variable consisting of (10) items, determining the degree of influence between the two variables. The study was tested on a sample of workers at Al-Kafeel Specialized Hospital affiliated with the Abbasid Shrine in Holy Karbala. The study population reached (600) workers. (338) questionnaires were distributed, and (14) questionnaires that were not suitable for analysis were excluded, leaving (324) questionnaires valid for analysis. The statistician showed that the sample represented 54% of the population, and the researchers aimed to achieve five respondents for each item. The research included correlation hypotheses, and the statistical program (SPSS.V.24) was adopted to analyze the results. The research reached acceptance of all hypotheses. The research reached a set of theoretical and applied conclusions, including that spiritual marketing works to raise the level of purchase intention among patients dealing with the hospital. The ability of employees to possess the ability to adopt (faith, moral, realism, and humanity) to gain customer loyalty.
Abstract: The study aims to design and build advanced systems to control the huge amount of information necessary to manage the economic unit and to ensure good and accurate information reaches all administrative levels appropriately and at the appropriate time to use it in making good decisions, To achieve this goal, the analytical descriptive approach was used through the use of the investigation form to present the opinion of the research sample, and the results of the research have shown that the application of accounting information systems leads to an increase in the ability of the economic unit to adapt to the advanced business environment, It also shows the importance of studying just in time and focusing on it constitutes a fundamental percentage in reducing costs. It leads to important savings in addition to non-financial effects to improve the reputation of economic unity. To achieve this goal, a questionnaire was designed as a tool to collect data, Some of the statistical methods (arithmetic, standard deviation) have been relied upon, as (10) questions are made up of four axes, and the answers were designed for each five -year -old (Likert) paragraph. The study reached the budget for the value of accounting information with the cost of its preparation and distribution. It is necessary to study how to get balance of the value of accounting information with the cost of its preparation and distribution
Abstract: In this article, we estimated the spectral envelope density function using the modified Daniell Kernel function for a non-stationarity time series, we solved the non-stationary problem by dividing the spectral envelope into a number of local spectral envelopes to reduce the effect of the trend, the time series used in the this article was the sequence of the nitrogenous bases of Escherichia coli bacteria's DNA. The problem of the article is dealing with categorical data in a non-stationary time series.