THE EFFECTS OF COVID-19 OUTBREAK ON
FINANCIAL MARKETS
Ismail ÇELIK, PhD
Tayfun YILMAZ, PhD
Süleyman EMIR
Ahmet Furkan SAK
Abstract
The purpose of this paper is to measure the risks posed
by the COVID-19 outbreak on financial market indicators, which
caused uncertainty and fear all over the world. In the paper, the
Fourier KPSS unit root test, which helps to measure structural
breaks more precisely by means of the Fourier transformations
in time series, the Fourier-SHIN Cointegration Test to determine
long-term relationships between time series, and the Fourier
Granger Causality Test to determine causality relationships are
used. As a result of these tests applied on the daily price series
between 31.12.2019 and 01.05.2020, it has been found that in
the long term, the COVID-19 outbreak has a significant effect on
stock markets, crude oil representing oil markets, and fear index;
but no significant effect on Bitcoin which represents money
markets. In the short term, it is concluded that COVID-19 has had
a significant effect on stock markets, crude oil, fear index, and
Bitcoin.
Associate Professor, Department of Banking and Finance, Burdur Mehmet Akif
Ersoy University, Turkey.
Assistant Professor, Department of Business, Burdur Mehmet Akif Ersoy
University, Turkey.
Lecturer, Department of Business Administration, National Defence University,
Turkey.
Research Assistant, Department of Business, Burdur Mehmet Akif Ersoy
University, Turkey.
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Financial Studies – 4/2020
Keywords: COVID-19, Fourier Transformations, Causality,
Cointegration, Financial Markets.
JEL Classification: C58, G15.
1. Introduction
Our world has experienced many diseases, wars, and disasters
globally and regionally since its formation. Those kinds of events have
had some direct and indirect effects on humanity in the short and long
term. Although, humanity has tried to minimize the effects of such
events with the precautions taken, the effects experienced have been
removed to some extent. Even if these effects disappeared or are
eliminated, this has taken a great time.
While the effects of regional disasters experienced in the past
were felt particularly in that region, nowadays, the events and
developments in any region of the world have direct and indirect global
effects. Without a doubt, the fact that today's world has become
globalized and integrated has a significant share in this. Today, we are
fighting the epidemic of COVID-19, which has and will continue to have
global effects similar to those in the past. It is useful to give brief
information about the epidemic. The new generation coronavirus
SARS COV 2 belongs to the same family of dangerous viruses such
as MERS and SARS. However, the most crucial feature that
distinguishes SARS COV 2 from these viruses is that it can be much
more contagious and, therefore, much more deadly. While this virus is
known to be widespread among animals, it has gained the feature of
spreading between humans as it evolves, and the new disease that
emerged with this evolution has been named COVID-19. The first case
of the outbreak occurred on December 1, 2019, in Wuhan, the capital
of China's Hubei region, and on December 31, this information was
confirmed by the China office of the World Health Organization. From
December 31, 2019 to January 3, 2020, the total number of cases
reached 44, with the first death on January 11, 2020. The World Health
Organization obtained information from the Chinese Health
Commission indicating that the outbreak occurred in a seafood market
in Wuhan city and declared a pandemic on March 11, 2020 as the
outbreak turned into a global threat (WHO, 2020)
It is a fact that this epidemic will cause many economic
problems, including financial markets. The epidemic continues to
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Financial Studies – 4/2020
spread while this article is written. There is no continent in the world
where the case is not seen, and the number of countries where the
case is not seen is just a few. It is a mystery exactly how much the
outbreak will spread in the future. However, the effects of the outbreak
that has and will have on finance and other areas in the future will be
of great interest to researchers.
This study considers only the process from the beginning of the
outbreak to become a global crisis, until the completion of the study
and aims to measure the impact of the outbreak on selected financial
markets and to lead to more comprehensive studies on this subject.
It is thought that this globally threatening epidemic will have an
impact on financial markets and lead to significant economic problems.
Based on the developments in past outbreaks, it is possible to make
predictions about the effects of this outbreak.
Even a non-global outbreak has adverse effects on trade,
travel, and tourism activities in the regions affected by the epidemic
considering the examples experienced in the past. For example, during
the HIV and AIDS epidemic, there was a permanent change in
consumer behavior, and a worldwide decline in expenditures and
domestic demand posed an important challenge for the global
economy (Haacker, 2004). Therefore, such long-term outbreaks
discourage foreign investments directly and indirectly and negatively
affect financial markets. Considering all these explanations, it is clear
that global and regional outbreaks in the past brought along some
problems. These problems are as follows (Bloom et al., 2018);
•
•
•
•
•
•
•
Increase in the health system costs,
The collapse of the health system as a result of excessive
demand for it, and difficulty in dealing with even routine health
problems,
Employment losses,
Retardation in the touristic activities
Problems in transportation and education,
Decreasing mobility in financial markets and experiencing
financial losses,
Slowdown in national and international trade
The adversities similar to those listed above and maybe, even
more, will also be seen in the outbreak of COVID-19. Countries should
always be prepared to prevent an epidemic and to overcome the
problems mentioned above with minimal damage. On the bright side,
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Financial Studies – 4/2020
countries do not have to invest considerable amounts in coping with
these problems. (Fan et al., 2018).
COVID-19 has had and will have many possible effects on the
financial markets included in this study. The outbreak is likely to pose
risks to banks, which are an essential element of the money markets,
during the period of the economic downturn due to the possibility of
non-performing loans and excessive bank transactions. It is expected
that the epidemic will have a long-term impact on companies related to
financing and capital costs. As regards the impact of the outbreak on
the financial markets, looking at what effects such recent terrorist
attacks and disasters have had on the financial markets will help to
understand the possible effects of the COVID-19 outbreak we are
experiencing (Goodell, 2020). Because, from past to present, a limited
number of studies investigated the effects of epidemic diseases on
financial markets (Al-Awadhi et al., 2020). In recent studies, it has been
determined that such disasters and terrorist events have a short-term
impact on financial markets (Brounen and Derwall, 2010).
In the light of these explanations, GDP is expected to decrease
by $130 billion in Turkey, and $9.170 billion throughout the world
(McKibbin and Fernando, 2020). This situation shows that the global
epidemic of COVID-19 harms the global economy on a scale not seen
since the Great Depression and will continue to cause considerable
damage to individual livelihoods, businesses, industries and the whole
economy (Laing, 2020).
2. Literature Review
There are several studies in the literature measuring the impact
of diseases and outbreaks on the financial markets. These studies
have mostly investigated the effects of outbreaks that arose in the past
like SARS, MERS, Ebola, AIDS on financial markets. The number of
studies evaluating the impact of COVID-19, which the world is
encountering and suffering nowadays on financial markets, is not
sufficient. The main reasons behind it are that the epidemic is brand
new and the difficulties encountered in reaching enough data to do
detailed analyzes. Accordingly, the studies about the current COVID19 outbreak and past illnesses and outbreaks are stated below.
Nippani and Washer (2004) investigated the impact of the
SARS outbreak on the financial markets of Thailand, Singapore, Hong
Kong, the Philippines, Indonesia, Canada, Vietnam, and China. In the
study, t-test and non-parametric Mann-Whitney tests were performed
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Financial Studies – 4/2020
in order to compare the data obtained between June 1, 2002 and
February 25, 2003 with the S&P 1200 global index. As a result of the
analysis, it is concluded that SARS has an impact on the Chinese and
Vietnamese stock markets and no negative impact on the stock
markets of other countries.
Loh (2006) investigated to what extent the airline companies
traded in the financial markets of Taylan, China, Canada, Hong Kong,
and Singapore are affected by SARS. For this purpose, F-test, SiegelTukey, Bartlett, Levene, and Brown tests were performed by using the
data obtained from December 1, 2002 to July 5, 2003. As a result of
the analysis, it is indicated that the epidemic harmed airline companies.
Giudice and Paltrinieri (2017) examined monthly flows and
performances of 78 equity mutual funds in African countries for the
period of 2006-2015. As a result of the analyzes and examinations, it
is concluded that two significant events, which are Ebola and the Arab
Spring, have significantly affected the funds flows, fund performance,
expenses, and market returns.
Chen et al. (2018) investigated the effects of SARS by
examining the long-term relationship between the stock exchanges of
Japan, Taiwan, Hong Kong, and Singapore, and the Chinese stock
market. For the study, they conducted a cointegration test using the
weekly data from 1998 to 2008 and concluded that the SARS outbreak
weakened the long-term relationship between the four financial
markets and China.
Goodell (2020) made comments and inferences about the
economic effects of the COVID-19 outbreak considering past
epidemics and disasters. He stated that this study will shed light on
future studies on COVID-19.
Nemec and Špaček (2020) focused on the macrosocioeconomic effects of the COVID-19 pandemic. They qualitatively
examined the information contained in the restrictive regulations of
national governments, data published by government bodies,
international statistics and media articles published before June 30,
2020 to investigate the impact of the pandemic on local budgets. The
Czech Republic and Slovakia were included in the scope of the
research and they concluded that the level of financial imbalance of the
COVID-19 crisis was not proportional to the situation at the central level
and that the municipal financial resources were not proportional to their
responsibilities as stated in the constitution. They stated that the
central administration in both countries is insufficient in combating the
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Financial Studies – 4/2020
pandemic and this will cause problems in many areas, especially in
culture and sports.
Ayittey et al. (2020) discussed the possible effects of
coronavirus on China and the world. They stated that China is likely to
lose 62 billion dollars in the first quarter of the year, and the world is
expected to lose more than 280 billion dollars in the same period.
Laing (2020) examined the effect of coronavirus on certain
precious metals. In order to measure the price changes, he compared
the prices of aluminum, copper, gold, lead, nickel, and zinc for the
period between March 4, 2020 and April 2, 2020. As a result of this
comparison, it is found that the price of aluminum, copper, gold, lead,
nickel, and zinc decreased by 15%, 14%, 2%, 10%, 11%, and 6%
respectively in the period given.
Estrada et al. (2020b) investigated the impact on the
performance of ten stock markets, including the FTSE to assess the
determinants of capital market behavior in the event of an infectious
disease outbreak, COVID-19's S&P 500, TWSE, Shanghai Stock
Exchange, Nikkei 225, DAX, Hang Seng, UK-FTSE, KRX, SGX and
Malaysia. As a result of the study, the researchers stated that the
epidemic could be disastrous for all countries' economies and could
cause similar damages to the 1929 Crisis on ten major stock markets
worldwide.
Luo and Tsang (2020) investigated the impact of the COVID-19
outbreak on China and the global economy. For this purpose, in order
to estimate output loss from labor loss by using a network approach,
they looked at how the decline in the labor force in Hubei province
affects production in China through input-output relations between
states. As a result of the analysis, they concluded that the Chinese
workforce had a production loss of about 4%, and global production
decreased by 1% due to the economic contraction in China. With this
result, they stated that approximately 40% of the impact is indirect,
resulting from supply chain spreads inside and outside China.
Estrada et al. (2020a) investigated how the coronavirus
outbreak affected China's economic performance. For the research,
they developed a new model called "Massive Infections and
Contagious Diseases Economic Simulator (IMICDE-Simulator)". In the
analysis performed to investigate the effects of the coronavirus, they
used the indicators given by the simulator and carried out the analysis
in this framework. As a result of the analysis, they concluded that the
epidemic reduced the potential growth of China by 2% compared to the
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Financial Studies – 4/2020
previous year, and this is three times more negative compared to the
one experienced in SARS. Besides, they mentioned that the epidemic
could have more impact on other economies.
Cepoi (2020) tried to measure the relationship between the
news about COVID-19 and stock market returns in the six countries
most affected by the pandemic (USA, UK, Germany, France, Spain
and Italy) using a panel regression model. Stock market return (RET),
The Panic Index (PI), The Media Hype Index (HY), The Fake News
Index (FNI), The Country Sentiment Index (CSI), The Contagion Index
(CTI), The Media Coverage Index (MCI), Sovereign CDS, Gold Price,
Sentiment Index, Intercept, Lagged Returns and Observations were
used. The analysis showed that exchanges offer asymmetric
correlation with information about COVID-19, such as fake news,
media coverage or contagion. In addition, it was observed that gold
yield has a positive non-linear correlation with stock markets and gold
is a “Safe Harbor” during the down-up periods. The results showed that
more intensive use of appropriate communication channels is required
to reduce the financial turmoil associated with COVID-19.
Zeren and Hizarcı (2020) conducted the Maki Cointegration
Test using the daily data of death and case numbers between January
23, 2020 and March 13, 2020 to determine the possible effects of the
COVID-19 outbreak on the stock markets. They found a parallel
movement between the number of deaths and the financial markets
included in the research, as well as a cointegration relationship
between the daily number of cases and SSE, KOSPI, and IBEX35. As
a result, they concluded that it would be much less risky for investors
to invest in gold markets, virtual currencies, derivatives markets, or
markets of countries where the epidemic is not observed during such
crisis periods.
Wójcık and Ioannou (2020) conducted a study on the actual
and potential impact of the pandemic on financial markets and sectors
and the tendency of the epidemic to affect the financial environment.
The study stated that a financial slowdown and a steady increase in
financial-related business services are expected, but local and regional
financial centers are likely to face greater challenges than leading
international centers.
Zhang, Hu, and Ji (2020) investigated the country-specific and
systematic risks COVID-19 poses to financial markets. For this
purpose, they collected the daily data of 12 countries from February 7,
2020 to March 27, 2020, and made a correlation analysis. As a result
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Financial Studies – 4/2020
of the correlation analysis, they concluded that the epidemic increased
not only national risks but also systematic risks in the financial markets
and stated that the epidemic caused uncertainty, risk, and economic
losses on the financial markets of these countries.
Al-Awadhi et al. (2020) have investigated the effect of the
coronavirus outbreak on financial markets. They included 82
companies operating in The Hang Seng Index and Shanghai Stock
Exchange Composite Index and divided them into ten sectors
according to their fields of activity. Then, they collected daily data of
validated cases, deaths, and stock market values of companies from
January 10, 2020 to March 16, 2020. By using panel data analysis,
they concluded that the number of daily confirmed cases and daily
death cases had significant negative effects on the financial markets of
the countries included in the study.
3. Methodology
The fact that financial assets have unit roots causes permanent
effects on the value of the financial asset due to some random shocks.
Exposure of non-stationary series to shock causes high degree
fluctuations to persist (Yılancı, 2017). Therefore, revealing the
existence of the unit root gained importance, especially in the 1980s.
Failure to measure the stationary of financial time series in
which short and long-term relationships are investigated, in the
presence of structural breaks with sensitive tests may cause changes
in analysis results and unsubstantial interpretations.
As the structural changes lead to large-scale changes in the
prices of non-stationary financial assets, the need for developing unit
root tests, taking into account a series of structural breaks pioneered
by Perron (1989) has increased. Unlike Perron (1989) unit root test,
based on the assumption that structural breaks are known, Zivot and
Andrews (1992), Lumsdaine and Papell (1997), Lee and Strazicich
(2003, 2004) developed unit root tests investigating the existence of
unit root under the assumption of one or two structural breaks with an
unknown date. In particular, Lee and Strazicich (2003, 2004)
introduced the LM to eliminate the shortcomings of the ZA and LP unit
root tests stating that in ZA and LP tests, the rejection of the H0
hypothesis will not require rejecting the existence of the unit root
(Yılancı, 2009).
Although the unit root tests mentioned above, which take into
account the structural breaks, assume that the structural break dates
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Financial Studies – 4/2020
are unknown, the structural breaks of the series which are tested for
unit root existence, are determined in a preliminary form.
In ADF-type unit root tests, the null hypothesis suggests that
the series has a unit root process while in KPSS-type tests, the null
hypothesis states that the series is stationarity. KPSS type stationary
test proposed by Kwiatkowski et al. (1992) has been developed by
Becker et al. (2006). In this unit root test, structural changes are taken
into account using the Fourier function. Thanks to the Fourier functions,
changes in the series can be precisely estimated. Since the number,
structure, and position of the structural changes are difficult to predict,
the Fourier functions eliminate this imperative and allow getting better
results. The unit root, cointegration and causality tests, which enable
the coefficients to be transformed into trigonometric form with the help
of the Fourier transformations, also take into account the effects of
external shocks such as structural breaks that financial time series are
exposed to. The tests applied in the Fourier form help to make accurate
analyzes in financial time series where structural breaks are observed.
The data generation process for the stationary test developed
by Becker et al. (2006) is as follows:
𝑌𝑡 = 𝑋𝑡′ 𝛽 + 𝑍𝑡′ 𝛾 + 𝑟𝑡 + 𝜖𝑡
(1)
𝑟𝑡 = 𝑟𝑡−1 + 𝑢𝑡
(2)
where 𝜖𝑡 is a stationary process and 𝑢𝑡 is a constant variance i.i.d. is a
process.
In the first stage, in order to calculate the test statistics required
to test the stationarity hypothesis, one of the following two models is
estimated and residuals are obtained:
𝑦𝑡 = 𝛿0 + 𝛿1 𝑠𝑖𝑛 (
2𝜋𝑘𝑡
2𝜋𝑘𝑡
) + 𝛿2 𝑐𝑜𝑠 (
) + 𝑣𝑡
𝑇
𝑇
𝑦𝑡 = 𝛿0 + 𝛽𝑡 + 𝛿1 𝑠𝑖𝑛 (
2𝜋𝑘𝑡
2𝜋𝑘𝑡
) + 𝛿2 𝑐𝑜𝑠 (
) + 𝑣𝑡
𝑇
𝑇
(3)
(4)
While the stationary at level hypothesis is tested with the model
(3), the trend stationarity hypothesis is tested using the model (4).
Test statistics can be calculated with the following formula:
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Financial Studies – 4/2020
2
̃
1 ∑𝑇
𝑡=1 𝑆𝑡 (𝑘)
̃2
𝜎
𝜏𝜇 (𝑘) or 𝜏𝜏 (𝑘) = 𝑇 2
(5)
where 𝑆̃𝑡 (𝑘) = ∑𝑡𝑗=1 𝑒̃𝑗 and 𝑒̃𝑗 is the residuals from the model (3) or (4).
A non-parametric estimation of 𝜎 can be obtained by selecting
lag parameter 𝑙 and 𝑤𝑗 , 𝑗 = 1,2, … , 𝑙 as follows:
2
𝑙
𝛿 = 𝛾̃0 + 2 ∑ 𝑤1 𝛼̃𝑗
(6)
𝑗=1
where 𝛼̃𝑗 is the 𝑗. sample autocovariance of the residuals from the
model (3) or (4).
The significance of the Fourier function is tested using the F
test statistic. The F test statistic for the Fourier model with K frequency
is as follows:
𝐹𝑖 (𝑘) =
(𝑆𝑆𝑅0 − 𝑆𝑆𝑅1 (𝑘))/2
, 𝑖 = 𝜇, 𝜏.
𝑆𝑆𝑅1 (𝑘)/(𝑇 − 𝑞)
(7)
where 𝑆𝑆𝑅1 (𝑘) is the sum of the residual squares obtained from the
regression equation (7), 𝑞 is the number of explanatory variable and
𝑆𝑆𝑅0 represents the sum of the residual squares obtained from the
model in which trigonometric terms are not added. In order to use the
F test, the stationary hypothesis must not be rejected. Suitable critical
values for the F test and stationary test are included in the study of
Becker et al. (2006) as a table.
In the literature, there are numerous cointegration tests
developed by Engle-Granger (1987), Gregory-Hansen (1996),
Johansen et al. (2000), Hatemi-J (2008) and so on. However, these
tests require to determine the number and form of structural changes
previously. The new cointegration test developed by Tsong et al.
(2016) takes into account unknown form and number of structural
breaks by using the Fourier trigonometric functions. This new method
called Fourier-Shin Cointegration Test considers the cointegration
regression equation as follows:
𝑦𝑡 = 𝑑𝑡 + 𝑥𝑡′ 𝛽 + 𝑛𝑡 ,
𝑡 = 1,2, … , 𝑇
15
(8)
Financial Studies – 4/2020
where 𝑛𝑡 = 𝛾𝑡 + 𝑣1𝑡 , 𝛾𝑡 = 𝛾𝑡−1 + 𝑢𝑡 with 𝛾0 = 0, and 𝑥𝑡 = 𝑥𝑡−1 + 𝑣2𝑡 .
Here 𝑢𝑡 is an iid process with zero mean and variance 𝜎𝑢2 . Therefore,
𝛾𝑡 is a random walk with mean zero. The deterministic component 𝑑𝑡 in
Eq. (8) can be defined as follows:
𝑚
𝑑𝑡 = ∑ 𝛿𝑖 𝑡 𝑖 + 𝑓𝑡 , 𝑚 = 0 𝑜𝑟 𝑚 = 1
𝑖=0
𝑓𝑡 = 𝛼𝑘 𝑠𝑖𝑛 (
2𝑘𝜋𝑡
2𝑘𝜋𝑡
) + 𝛽𝑘 𝑐𝑜𝑠 (
)
𝑇
𝑇
(9)
(10)
where (𝑘) denotes the Fourier frequency value, 𝑡 is trend, and 𝑇
represents the sample size. The null hypothesis of cointegration
against the alternative of non-cointegration could be expressed as:
𝐻0 : 𝜎𝑢2 = 0 𝑣𝑒𝑟𝑠𝑢𝑠 𝐻1 : 𝜎𝑢2 > 0
(11)
In order to test the null hypothesis in Eq. (11), the model
described in equation (9), (10) could be rephrased as:
𝑚
𝑦𝑡 = ∑ 𝛿𝑖 𝑡 𝑖 + 𝛼𝑘 𝑠𝑖𝑛 (
𝑖=0
2𝑘𝜋𝑡
2𝑘𝜋𝑡
) + 𝛽𝑘 𝑐𝑜𝑠 (
) + 𝑥𝑡′ 𝛽 + 𝑣1𝑡
𝑇
𝑇
(12)
The FSHIN Cointegration test statistic (denoted by 𝐶𝐼𝑓𝑚 ) to test
the null of cointegration with structural breaks against the alternative of
non-cointegration is given by:
𝐶𝐼𝑓𝑚
=𝑇
−2
𝑤
̂
−2
𝑇
∑ 𝑆𝑡2
(13)
𝑡=1
where 𝑆𝑡 = ∑𝑇𝑡=1 𝑣̂1𝑡 is the partial sum of the ordinary least squares
(OLS) residuals from Eq. (12) and 𝑤12 denotes the consistent estimator
for the long variance of 𝑣1𝑡 .
In the study, the existence of the causality relationship between
variables was investigated with the Fourier Granger causality test
developed by Enders and Jones (2015). Enders and Jones (2015)
introduced a flexible Fourier form to capture changes in multiple soft
averages in a short-term VAR system. The authors limited the VAR
model by forcing the limitations envisaged by the Granger causality test
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Financial Studies – 4/2020
to take into account the effect of neglecting structural breaks in a linear
VAR model on Granger causality tests. The findings of the authors
showed that there was little interaction between the variables and that
the significant responses are such that series tend to respond only to
their own shocks.
The authors then defined the deterministic regressors as
follows:
11
𝑧𝑡 = 𝛿(𝑡) + ∑ 𝐴İ 𝑧𝑡−1 + 𝑒𝑡
(14)
1
𝛿(𝑡) = [𝛿1 (𝑡), 𝛿2 (𝑡), 𝛿3 (𝑡), 𝛿4 (𝑡)]′
(15)
and each intercept 𝛿𝑖𝑡 depends on n Fourier frequencies such that:
𝑛
𝛿𝑖 (𝑡) = 𝛼𝑖 + 𝑏𝑖 𝑡 + ∑ 𝛼𝑖𝑘 𝑠𝑖𝑛 (
𝑘=1
2𝜋𝑘𝑡
2𝜋𝑘𝑡
) + 𝑏𝑖𝑘 𝑐𝑜𝑠 (
)
𝑇
𝑇
(16)
Unlike the Granger causality results obtained from the linear VAR
model, Enders and Jones (2015) found stronger relationships and
richer sets of interactions between the variables by adding
trigonometric functions to the model.
4. Data and the Empirical Results
In this study, the effect of the COVID-19 outbreak on financial
markets is evaluated. The results and findings obtained are important
for people who play an active role in the stock market to understand
and predict stock returns and movements during the pandemic.
For this purpose, the period between 31.12.2019 and
01.05.2020 is included in the study. Daily data are used for all price
series included in the study. In order to evaluate the effects of
coronavirus on financial markets, some financial markets are included
in the research. These are; the Italian stock market (FTSE MIB), the
French stock market (CAC 40), the British stock market (FTSE 100),
the Chinese stock market (SHANGAI), and the Fear Index (VIX). In
addition, ounces of gold (OUNCE) representing the precious metal
market, crude oil (WTI) representing the energy market, and bitcoin
(BTC) representing the cryptocurrency market are among the items to
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Financial Studies – 4/2020
be examined in the study. All these elements mentioned above
constitute the dependent variables of the study.
Total Verified Number of Cases (TVNC), Total Verified Number
of Deaths (TVND), Number of Daily Cases (NDC), and Number of Daily
Deaths (NDD) are chosen as independent variables of the study. Data
on these variables are obtained from the website "ourworldindata.org".
The line graphs of Number of Daily Cases (NDC), Number of Daily
Deaths (NDD), Total Verified Number of Cases (TVNC), and Total
Number of Verified Deaths (TNVD-), which are the independent
variables of the study, are shown in Figure 1.
Figure 1
Daily price series regarding independent variables
Number of Daily Cases (NDC)
Number of Daily Deaths (NDD)
120,000
12,000
100,000
10,000
80,000
8,000
60,000
6,000
40,000
4,000
20,000
2,000
0
0
6 13 20 27 3 10 17 24 2
M1
M2
9 16 23 30 6 13 20 27
M3
6 13 20 27 3 10 17 24 2
M4
M1
Total Verified Number of Cases (TVNC)
M2
9 16 23 30 6 13 20 27
M3
M4
Total Verified Number of Deaths (TVND)
4,000,000
240,000
200,000
3,000,000
160,000
2,000,000
120,000
80,000
1,000,000
40,000
0
0
6 13 20 27 3 10 17 24 2
M1
M2
9 16 23 30 6 13 20 27
M3
M4
6 13 20 27 3 10 17 24 2
M1
M2
9 16 23 30 6 13 20 27
M3
M4
Daily price series of the study’s dependent variables which are
the Italian stock market (FTSEMIB), the French stock market (CAC40),
the British stock market (FTSE100), the Chinese stock market
(SHANGAI), the Fear Index (VIX), Bitcoin (BT-C), Ounce of Gold
(OUNCE) and Crude Oil (WTI) are shown in Figure 2.
18
Financial Studies – 4/2020
Figure 2
Daily price series regarding dependent variables
CAC40
FTSE100
FTSE_MIB
6,500
8,000
26,000
6,000
7,500
24,000
7,000
5,500
22,000
6,500
5,000
20,000
6,000
4,500
18,000
5,500
4,000
5,000
3,500
4,500
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
16,000
14,000
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
SHANGAI COMPOSITE
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
OUNCE
3,200
1,750
3,100
1,700
3,000
1,650
2,900
1,600
2,800
1,550
2,700
1,500
VIX
100
80
60
40
2,600
20
1,450
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
0
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
WTI
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
BTC
70
11,000
60
10,000
50
9,000
40
8,000
30
7,000
20
6,000
10
5,000
4,000
0
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
6 13 20 27 3 10 17 24 2 9 16 23 30 6 13 20 27
M1
M2
M3
M4
When the charts of all financial assets as of March 2020 are
analyzed, it can be seen that significant decreases occurred in all
financial markets and the VIX index increased.
In order to evaluate the effect of COVID-19 outbreak on
financial markets, the effects of changes in Number of Daily Cases
(NDC), Number of Daily Deaths (NDD), Total Verified Number of
Cases (TVNC) and Total Number of Verified Deaths (TNVD) on the
Italian stock market (FTSE_MIB), the French stock exchange
(CAC40), the British stock exchange (FTSE100), the Chinese stock
exchange (SHANGAI), the Fear Index (VIX), Bitcoin (BTC), Ounce of
Gold (OUNCE) and Crude Oil (WTI) are investigated.
19
Financial Studies – 4/2020
First of all, it is necessary to conduct a stationarity test for the
variables mentioned above. As mentioned in the methodology section,
the FKPSS unit root test is implemented in the study. In the FKPSS
unit root test, the null hypothesis is that the series is stationary. The
test results are given in Table 1.
Table 1
Fourier KPSS Unit Root Test Results
Level
lnTVNC
lnNDC
lnNDD
lnTVND
lnBTC
lnCAC40
lnFTSE100
lnFTSEMIB
lnOUNCE
lnSHANGAI
lnVIX
lnWTI
1st Diff.
D(lnTVNC)
D(lnNDC)
D(lnNDD)
D(lnTVND)
D(lnBTC)
D(lnCAC40)
D(lnFTSE100)
D(lnFTSEMIB)
D(lnOUNCE)
D(lnSHANGAI)
D(lnVIX)
D(lnWTI)
Frequency
1
1
1
1
1
1
1
1
2
1
1
1
Frequency
2
2
2
2
1
1
2
2
3
3
1
3
Min SSR
1485558
1647999
9529202
1746269
0.241005
0.096856
0.069726
0.125325
0.022441
0.021829
1105033
3823441
Min SSR
1647679
2454385
2207312
1920076
0.363565
0.066110
0.056192
0.087364
0.015825
0.019820
1140474
0.561779
FKPSS
0.511249***
0.423009***
0.470167***
0.512016***
0.218039**
0.196760**
0.235439**
0.175856**
0.754373***
0.225168**
0.172377**
0.473817***
FKPSS
0.329952
0.072922
0.086305
0.300619
0.035919
0.051429
0.124419
0.129699
0.040886
0.138465
0.052856
0.157658
KPSS
KPSS
0.387836
0.229203
0.084105
0.259411
0.123260
0.124777
0.132399
0.125102
0.035977
0.065277
0.182625
0.331187
F Stat.
60.32***
47.54***
77.38***
64.80***
123.39***
308.32***
347.18***
289.71***
33.14***
48.60***
422.29***
62.35***
F Stat.
1.895
2.935
1.374
1.906
1.906
2.152
1.812
2.105
1.443
1.352
2.305
1.052
***, ** and * represent 1%, 5% and 10% significance levels respectively. Null
Hypothesis “… is stationary”.
As can be seen in Table 1, according to the FKPSS Test results
at the level, the test statistics for all series are greater than the critical
values. Therefore, the null hypothesis stating that the series is
stationary is rejected for all series. The ability to test the significance of
trigonometric terms depends on the precondition that the null
hypothesis cannot be rejected (Yılancı, 2017). Since the null
hypothesis was rejected in level values for all series, both the FKPSS
20
Financial Studies – 4/2020
test statistics and the F test were applied for the differentiated series.
It was determined that all series were stationary after taking the first
difference. Since the test statistics are less than critical values for all
series, the null hypotheses stating that the series is stationary are not
rejected. Since it was found that trigonometric terms with the Fourier
transformation are not significant, the series are found to be stationary
at the first difference according to the standard KPSS test. In brief,
according to the results of Table 1, all series are determined to be I[1].
The Fourier – Shin Cointegration Test Results
Frequency
NDC - BTC
NDC - CAC40
NDC - FTSE100
NDC - FTSEMIB
NDC - OUNCE
NDC - SHANGAI
NDC - VIX
NDC - WTI
NDD - BTC
NDD - CAC40
NDD - FTSE100
NDD - FTSEMIB
NDD - OUNCE
NDD - SHANGAI
NDD - VIX
NDD - WTI
TVNC - BTC
TVNC - CAC40
TVNC - FTSE100
TVNC - FTSEMIB
TVNC - OUNCE
TVNC - SHANGAI
TVNC - VIX
TVNC - WTI
TVND - BTC
TVND - CAC40
TVND - FTSE100
TVND - FTSEMIB
TVND - OUNCE
TVND - SHANGAI
TVND - VIX
TVND - WTI
2
2
2
2
1
3
2
1
2
2
2
2
1
2
2
1
1
2
2
2
1
2
2
1
1
2
2
2
1
2
2
1
Min
SSR
9.805.982
3.710.850
3.296.216
4.401.541
1.090.769
3.383.122
2.382.989
5.230.376
3.668.248
7.102.348
6.077.856
1.105.621
5.262.592
1.870.958
8.594.228
2.593.334
7.333.911
2.785.453
2.273.288
3.616.061
5.092.151
2.737.019
1.050.194
3.176.993
8.765.947
2.783.411
2.273.980
3.658.908
5.805.349
3.491.393
1.119.943
3.664.198
21
Fourier
Cointeg.
Test Stat.
0.4888***
0.2029
0.1696
0.2460
0.1978**
0.2512
0.0916
0.0988
0.4804***
0.1651
0.1045
0.2526
0.2061***
0.3133**
0.2088
0.1129
0.2841***
0.2619
0.2285
0.3035**
0.1856**
0.2492
0.1130
0.1334**
0.2903***
0.2372
0.1964
0.2877**
0.1898**
0.2531
0.1153
0.1458**
Shin
Stat.
Test
0.8387***
0.2966
0.2656
0.3336**
0.5562***
0.2577
0.2628
0.3046
0.9504***
0.3168**
0.2866
0.3691**
0.6467***
0.5406***
0.4008**
0.3916**
0.9532***
0.3701**
0.3354**
0.4101**
0.7075***
0.4403**
0.3787**
0.4127**
0.9691***
0.3758**
0.3429**
0.4136**
0.7397***
0.4679**
0.4013**
0.4214**
Table 2
F Stat.
13.590***
11.3946***
14.334***
9.593***
0.503
3.802***
35.229***
2.667
46.611***
114.448***
232.315***
53.749***
4.170**
22.030***
244.647***
4.555**
12.836***
20.072***
39.524***
19.700***
4.507**
49.129***
151.003***
10.721***
9.701***
36.160***
68.761***
27.272***
4.775**
29.971***
160.686***
9.383***
Financial Studies – 4/2020
Fourier Cointeg. Critical Values
1%
5%
10%
k=1
0.198
0.124
0.095
k=2
0.473
0.276
0.200
k=3
0.507
0.304
0.225
F-Stat.
Critical
Values
1%
5%
10%
5.774
4.066
3.352
SHIN Critical Value
1%
5%
10%
0.533
0.314
0.231
***, ** and * represent 1%, 5% and 10% significance levels respectively. "null
hypothesis; “There is a significant long-term relationship between variables.”
According to the degrees of freedom associated with the
Fourier cointegration test statistics in Table 2, the results of the Fourier
cointegration test statistics for NDC-CAC40, NDC-FTSE100, NDC
FTSEMIB, NDC-SHANGAI, NDC-VIX, NDC-WTI, NDD-CAC40, NDD
FTSE100, NDD-FTSEMIB, NDD-VIX, NDD-WTI, TVNC-CAC40,
TVNC-FTSE100, TVNC-SHANGAI, TVNC-VIX, TVND-CAC40, TVNDFTSE100, TVND-SHANGAI and TVND-VIX are smaller than FSHIN
critical values. For example, the Fourier cointegration test statistic for
NDC-CAC40 (0.2029) is less than the FSHIN critical value of k=2 for
5% significance level (0,276). In this case, "H0: There is a significant
long-term relationship between variables" hypothesis could not be
rejected. It is seen that all the financial stock markets mentioned above
have a long-term relationship with daily cases/deaths (NDC and NDD)
and total cases/deaths (TVNC and TVND).
Test statistics for NDC-BTC, NDC-OUNCE, NDD-BTC, NDDOUNCE, NDD-SHANGAI, TVNC-BTC, TVNC-FTSEMIB, TVNCOUNCE, TVNC-WTI, TVND-BTC, TVND-FTSEMIB, TVND-OUNCE,
TVND-WTI are greater than the critical values with respect to degrees
of freedom. For example, the Fourier cointegration test statistic for
NDC-BTC (0.4888) is less than the FSHIN critical value of k=2 for 5%
significance level (0,276). In this case, H0 hypothesis is rejected. No
relation has been found for the cointegration results in question. Also,
according to the results of the F-statistic which shows the significance
of the trigonometric coefficients, the F-Statistics values of NDCOUNCE and NDC-WTI are smaller than the critical values. Therefore,
the H0 hypothesis of F-statistics could not be rejected, and it was
concluded that the results were not significant. The F-Statistics values
apart from NDC-OUNCE and NDC-WTI are greater than all of the
critical values, so the results are meaningful. The results obtained with
the F-Statistic are consistent with the results mentioned above, in
which case, the results of the Fourier Cointegration test statistics are
22
Financial Studies – 4/2020
reliable. For NDC-OUNCE and NDC-WTI, whose F-statistic values are
insignificant, the SHIN cointegration test was applied, and a significant
relationship between NDC and OUNCE and insignificant relationship
between NDC and WTI has been found.
Table 3
The Fourier Granger causality test results
lnNDC→lnBTC
lnNDC→lnCAC40
lnNDC→lnFTSE100
lnNDC→lnFTSEMİB
lnNDC→lnOUNCE
lnNDC→lnSHANGAI
lnNDC→lnVIX
lnNDC→lnWTI
lnNDD→lnBTC
lnNDD→lnCAC40
lnNDD→lnFTSE100
lnNDD→lnFTSEMIB
lnNDD→lnOUNCE
lnNDD→lnSHANGAI
lnNDD→lnVIX
lnNDD→lnWTI
lnTVNC→lnBTC
lnTVNC→lnCAC40
lnTVNC→lnFTSE100
lnTVNC→lnFTSEMIB
lnTVNC→lnOUNCE
lnTVNC→lnSHANGAI
lnTVNC→lnVIX
lnTVNC→lnWTI
lnTVND→lnBTC
lnTVND→lnCAC40
lnTVND→lnFTSE100
lnTVND→lnFTSEMIB
lnTVND→lnOUNCE
lnTVND→lnSHANGAI
lnTVND→lnVIX
lnTVND→lnWTI
Enders Jones Single Frequency
Wald Stat.
Asymptotic
p-value
6.606
0.010***
4.141
0.042**
4.173
0.041**
3.998
0.046**
4.613
0.032**
2.405
0.121
3.265
0.071*
5.617
0.018**
3.739
0.053*
0.611
0.434
0.382
0.536
0.638
0.424
2.604
0.107
1.292
0.256
1.407
0.236
2.479
0.115
5.577
0.018**
7.142
0.008***
3.211
0.073*
2.219
0.136
4.617
0.032**
1.987
0.159
2.198
0.138
4.480
0.034**
4.516
0.034**
4.932
0.026**
5.162
0.023**
4.792
0.029**
6.069
0.014**
3.514
0.061*
3.939
0.047**
4.160
0.041**
Bootstrap
p-value
0.010**
0.060*
0.030**
0.060*
0.030**
0.150
0.090*
0.010**
0.050*
0.420
0.530
0.350
0.110
0.170
0.200
0.110
0.000***
0.000***
0.110
0.110
0.080*
0.100
0.070
0.040**
0.050*
0.020**
0.030**
0.050*
0.020**
0.050*
0.070*
0.060*
Optimal
Frequnecy
3
2
2
2
2
2
2
3
3
3
3
3
3
3
2
3
3
2
3
3
3
3
3
3
1
2
2
2
2
1
2
1
→ refers to causality. ***, ** and * represent 1%, 5% and 10% significance levels
respectively. In this study, as T (number of samples) > 50, asymptotic p values are used
in the analysis.
23
Financial Studies – 4/2020
According to the asymptotic p-values of the Fourier Granger
Causality test given in Table 3, it has been found that there is causality
from Number of Daily Cases (NDC) to BTC at 1% significance level,
and to CAC40, FTSE100, FTSEMIB, OUNCE, WTI at 5% significance
level; from Number of Daily Deaths (NDD) to BTC at 10% significance
level; from Total Verified Number of Cases (TVNC) to CAC40 at 1%
significance level, and to BTC, OUNCE, WTI at 5% significance level,
and to FTSE100 at 10% significance level; and lastly, from Total
Number of Verified Deaths (TNVD) to BTC, CAC40, FTSE100,
FTSEMIB, OUNCE, VIX, WTI at 5% significance level, and to
SHANGAI at 10% significance level.
5. Conclusions
The COVID-19 outbreak, which started in Wuhan, China,
caused great panic and impact worldwide. The economic effects of the
pandemic. which reached almost the whole world, has become more
and more evident day by day. The COVID-19 epidemic caused a large
interruption of production in the USA and China, which are seen as the
largest economies in the world and competing with each other, as well
as other countries, and price changes in oil, gold, cryptocurrencies and
many other sectors and areas. The fact that the countries that have a
big voice in the world economy are desperate against this threat affects
and will continue to affect the whole world. It is a mystery what the
effects of COVID-19, which we are currently living in, and do not know
exactly what the effects and results will be on the financial markets in
the short and long term.
Accordingly, in this study, the effects of COVID-19, which is
accepted as a pandemic, on stock markets representing the financial
markets, the gold ounce representing the precious metals, the crude
oil representing the energy market, and Bitcoin representing the
cryptocurrency markets were investigated separately. While
performing these analyzes, in determining causal relationships or longterm relationships, the Fourier SHIN Cointegration Test and Ender and
Jones Causality Tests were used for the Fourier transformation of the
equations. As a result of the analysis, it has been found that the
COVID-19 outbreak has a significant long-term effect on stock
markets, crude oil representing the oil markets and the fear index, while
has no long-term effect on bitcoin representing money markets. As for
the short-term effects of COVID-19, it has been found that the
24
Financial Studies – 4/2020
pandemic has an effect on stock markets, crude oil, fear index, and
bitcoin.
In light of all these explanations, it has been determined that
COVID-19 has both the short and long-term effects on cryptocurrency
markets, precious metal markets, the stock indices representing
financial markets that will cause price movements.
The most important contribution of this study to the literature is
that with a limited data set of the COVID 19 process, stationarity,
cointegration, and causality relationships of the Fourier
transformations, which is a new method considering the effects of
structural shocks (smooth transition) on financial time series is used.
References
Al-Awadhi, A. M., Alsaifi, K., Al-Awadhi, A. and Alhammadi, S. (2020).
Death and Contagious Infectious Diseases: Impact of the COVID-19
Virus on Stock Market Returns. Journal of Behavioral and
Experimental Finance, 27, pp.1-5.
Ayittey, F. K., Ayittey, M. K., Chiwero, N. B., Kamasah, J. S. & Dzuvor,
C. (2020). Economic impacts of Wuhan 2019‐nCoV on China and the
World. Journal of Medical Wirology, 10.1002/jmv.25706, pp. 1-3.
Becker, R., Enders W. and Lee, J. (2006). A Stationarity Test in the
Presence of an Unknown Number of Smooth Breaks. Journal of Time
Series Analysis, 27(3), pp. 381–409.
Bloom, D. E., Cadarette, D. and Sevilla, J. (2018). New and Resurgent
Infectious
Diseases
Can
Have
Far-Reaching
Economic
Repercussions. Finance and Development, 55(2), pp. 46-49.
Brounen, D. and Derwall, J. (2010). The Impact of Terrorist Attacks on
International Stock Markets. European Financial Management, 16(4),
pp. 585-598.
Cepoi, C.O. (2020). Asymmetric Dependence Between Stock Market
Returns and News During COVID-19 Financial Turmoil, Finance
Research Letters, 36, 101658.
Chen, M.-P., Lee, C.-C., Lin, Y.-H. and Chen, W.-Y. (2018). Did the
SARS Epidemic Weaken the Integration of Asian Stock Markets?
Evidence from Smooth Time Varying Cointegration Analyisis.
Economic Research, 31, pp. 908-926.
Enders, W. and Jones, P. (2015). Grain Prices, Oil Prices, and Multiple
Smooth Breaks in a VAR. Studies in Nonlinear Dynamics &
Econometrics, 20(4), pp. 399-419.
25
Financial Studies – 4/2020
Engle R. F. and Granger C.W.J. (1987). Cointegration and Error
Correction: Representation, Estimation, and Testing. Econometrica,
55(2), pp. 251–276.
Estrada, M.A., Park, D., Koutronas, E., Khan, A. and Tahir, M.
(2020a). The Economic Impact of Massive Infectious and Congagious
Diseases: The Case of Wuhan Coronavirus. Available at SSRN:
https://ssrn.com/abstract=3533771
or
http://dx.doi.org/10.2139/ssrn.3527330
Estrada, M.A., Koutronas, E., and Lee, M. (2020b). Stagpression: The
economic and financial impact of Covid-19 Pandemic, SSRN
Electronic Journal, January 2020.
Fan, V. Y., Dean, T. J. and Summers, L. H. (2018). Pandemic Risk:
How Large are the Expected Losses? Bulletin of The World Health
Organization, 96(2), pp. 129-134.
Giudice, A. D. and Paltrinieri, A. (2017). The Impact of the Arab Spring
and the Ebola Outbreak on African Equity Mutual Fund Investor
Decisions. Research in International Business and Finance, 41, pp.
600-612.
Goodell, J. W. (2020). COVID-19 and Finance: Agendas for Future
Research. Finance Research Letters, 35, pp.101512.
Gregory A.W. and Hansen B.E. (1996). Residual-based Tests for
Cointegration in Models with Regime Shifts. Journal of Econometrics,
70, pp. 99-126
Haacker, M. (2004). The Impact of HIV/AIDS on Government Finance
and Public Services. International Monetary Fund, Washington, pp.
198-258.
Hatemi-J, A. (2008). Tests for Cointegration with Two Unknown
Regime Shifts with an Application to Financial Market Integration.
Empirical Economics, 35(3), pp. 497-505.
Johansen, S., Mosconi, R. and Nielsen, B. (2000). Cointegration
Analysis in the Presence of Structural Breaks in the Deterministic
Trend. The Econometrics Journal, 3(2), pp. 216-249.
Kwiatkowski, D., Phillips, P. C., Schmidt, P. and Shin, Y. (1992).
Testing the Null Hypothesis of Stationarity Against the Alternative of a
Unit Root: How Sure Are We that Economic Time Series Have a Unit
Root?. Journal of Econometrics, 54(1-3), pp. 159-178.
26
Financial Studies – 4/2020
Laing, T. (2020). The Economic Impact of the Coronavirus 2019
(Covid-2019): Implications for the Mining Industry. The Extractive
Industries and Society, (access date 16.05.2020), pp. 1-4.
Lee, J., and Strazicich, M. C. (2003). Minimum Lagrange Multiplier
Unit Root Test with Two Structural Breaks. Review of Economics and
Statistics, 85(4), pp. 1082-1089.
Lee, J., and Strazicich, M. C. (2004). Minimum LM Unit Root Test with
One Structural Break. Manuscript, Department of Economics,
Appalachian State University, 33(4), pp. 2483-2492.
Loh, E. (2006). The Impact of SARS on the Performance and Risk
Profile of Airline Stocks. International Journal of Transport Economics,
33(2), pp. 401-422.
Lumsdaine, R.L. and Papell, D.H. (1997). Multiple Trends and the Unit
Root Hypothesis. The Review of Economics and Statistics, 79, pp.
212–218.
Luo, S. and Tsang, K. P. (2020). How Much of China and World GDP
Has the Coronavirus Reduced? Available at SSRN 3543760, pp. 116.
McKibbin, W. and Fernando, R. (2020). The global macroeconomic
impacts of COVID-19: Seven scenarios, (access date 02.03.2020)
https://www.brookings.edu/wpcontent/uploads/2020/03/20200302_COVID19.pdf, pp. 1-43.
Nemec, J. and Špaček, D. (2020), The Covid-19 Pandemic and Local
Government Finance: Czechia And Slovakia. Journal of Public
Budgeting, Accounting & Financial Management.
Nippani, S. and Washer, K. M. (2004). SARS: a Non-event for Affected
Countries' Stock Markets? Applied Financial Economics, 14(15), pp.
1105-1110.
Perron, P. (1989). The Great Crash, the Oil Price Shock and the Unit
Root Hypothesis. Econometrica, 57, pp. 1361–1401.
Tsong, C. C., Lee, C. F., Tsai, L. J. and Hu, T. C. (2016), The Fourier
Approximation and Testing for the Null of Cointegration, Empirical
Economics, 51(3), pp. 1085-1113.
WHO. (2020). Novel Coronavirus (2019-nCoV) Situation Report 1.
pp.1-5.
Wójcık, D. and Loannou, S. (2020). COVID-19 and Finance: Market
Developments So Far and Potential Impacts On The Financial Sector
27
Financial Studies – 4/2020
and Centres. Journal of Economic and Social Geography, 111(3), pp.
387-400.
Yılancı, V. (2009). Yapısal Kırılmalar Altında Türkiye için İşsizlik
Histerisinin Sınanması. Doğuş Üniversitesi Dergisi, 10(2), pp. 324335.
Yılancı, V. (2017). Analysing the relationship between oil prices and
economic growth: A fourier approach. Ekonometri ve İstatistik eDergisi, 27, pp. 51-67.
Zeren, F. and Hizarcı, A. E. (2020). The impact of COVID-19
coronavirus on stock markets: evidence from selected countries.
Muhasebe
ve
Finans
İncelemeleri
Dergisi,
3(1),
DOI:10.32951/mufider.706159, pp. 78-84.
Zhang, D., Hu, M. and Ji, Q. (2020). Financial Markets Under the
Global Pandemic of COVID-19. Finance Research Letters, (access
date 16.04.2020), pp. 1-14.
Zivot, E. and Andrews, D.W.K. (1992). Further Evidence on the Great
Crash, the Oil-price Shocks, and the Unit-Root Hypothesis. Journal of
Business and Economic Statistics 10, pp. 251–270.
28