ABSTRACT
The COVID-19 pandemic brings significant effects to the global stock market, including Indonesia. This study investigates the behavior and fluctuation of Jakarta Composite Index (JKSE) before the COVID-19 pandemic arises (2018–2019) and 2 years during the COVID-19 pandemic (2020–2021) and its alignment with the government policy in the energy sector. This study will use the JKSE data before and during the Covid-19 pandemic. The study showed that before COVID-19 pandemic, the JKSE was in normal conditions and showed an increasing trend. However, the study found anomalies in the JKSE volatility when COVID-19 pandemic was officially announced in Indonesia during 1st quarter 2020. This study is able to find the forecasted next 30 days best models that can describe the pattern of JKSE data are AR (2)–GARCH (1,1) models for the closing price of JKSE data before the COVID-19 pandemic and AR (5)–GARCH (1,1) models for the closing price of JKSE data during the COVID-19 pandemic. With the government economic recovery program related to the energy sector, this study was able to forecast the next 30 days for the closing price of JKSE during COVID-19, which showed the improvement of JKSE into the small increasing trend. These findings are expected to increase public investor trust, especially foreign investors investing their money in the JKSE. The positive trend in JKSE will ensure the government continues its economic policy recovery plan. © 2023, World Scientific and Engineering Academy and Society. All rights reserved.
ABSTRACT
The coronavirus disease epidemic has been increasing rapidly, and it still has been in a state of concern since the first suspected case on December 1st, 2019, in Wuhan, Hubei Province, China. This study aims a dynamic model development for the coronavirus disease epidemic and to analyze its stability. The nonlinear differential system in the SEIQR model has five variables, namely Susceptible, Exposed, Infected, Quarantined, and Recovered. The model development was carried out by adding self-prevention parameters. The Basic Reproductive Number is obtained from the model by using the Next Generation Matrix method. Stability analyses for disease-free equilibrium (DFE) and model endemic equilibrium were conducted to observe system dynamics. DFE is stable if the basic reproduction number is less than unity and unstable if more than unity;the endemic point is stable if the basic reproduction number is more than unity and unstable if it is less than unity. The Lyapunov method is used to determine the global stability of the system. The dynamic system is globally asymptotically stable if the value of the scalar function must be positive and its first derivative must be negative. Numerical simulations are carried out to verify the proposed mathematical model. The parameter model was obtained by matching the SEIQR model with data on cases of the spread of the coronavirus in Central Java Province, Indonesia. In the results obtained R0 = 4.656556046 > 1 so that it can be declared endemic. © 2023 American Institute of Physics Inc.. All rights reserved.
ABSTRACT
Rice food security can be realized through increased production of irrigated rice fields. Still, floods and droughts due to extreme weather and the Covid-19 pandemic can threaten food production and security. This study aimed to determine the relationship between the participation of rice farmers in managing water resources on rice production during the Covid-19 pandemic. The study was conducted during the 2020 Covid-19 pandemic in South Konawe Regency, Southeast Sulawesi Province. The research population is all farmers who are members of the water-using farmers' association, 130 farmers. The sample will be selected using a simple random sampling method for 39 people. Variables of lowland rice farmers' participation in water resource management include planning, attendance, provision of fees, security and maintenance of water resources and lowland rice farming production. The data were analyzed using Chi-Square analysis. The results of this study indicate that the participation of rice farmers in managing water resources on rice production during the covid 19 pandemic in the form of planning, attendance, procurement of fees, and security in managing water resources is significantly related to lowland rice production during the Covid-19 pandemic so that Partially the higher the participation of farmers in managing water resources can increase the output of lowland rice and the availability of rice is always available to maintain regional food security.
ABSTRACT
The research was conducted to examine the effect of the consumers’ product familiarity on the purchase intention in fruits and vegetables in Malang city during the COVID-19 pandemic. The judgment sampling method was used to select the 176 respondents based on the purchasing criteria from either the online and offline market at least twice or more. The data were analyzed using multivariate data analysis with partial least squares structural equation modeling (PLS-SEM). The findings showed that product knowledge had a great influence on the familiarity with the product. Consumers were aware of the food safety provided by the company while purchasing online. In addition, the familiarity of the products also brought a positive influence on purchase intention. The social influence and preference of other people became a factor considered by the consumers in purchasing the fruits and vegetables. So, the company should improve the marketing and branding strategies of the products by continually prioritizing the safety of the consumers in accordance with the health protocols.