Dampak Pengumuman Covid-19 Terhadap Return Saham: Penelaahan Beberapa Sektor Industri

This Research is an event study that examine abnormal return difference before and after first announcement of covid-19 case in Indonesia. This Study use daily closing price data to calculate returns. We use 30 days estimation period and 20 days window period. The data collection method is purposive sampling. There are 64 companies that meet the establish criteria. Wilcoxon signed rank test and paired sample t-test were used to examine the difference in abnormal return before and after the covid-19 first case announcement in Hotel, Restaurant & Tourism, Banking and telecommunication sector. This study found that there was no difference in abnormal returns before and after the announcement of the first Covid-19 case in Hotel, Restaurant & Tourism and Banking sector. Furthermore, this study found differences in abnormal return before and after the announcement of the first covid 19 case in telecommunication sector. How to Cite:Sari, L., & Bone, H. (2021). Dampak Pengumuman Covid-19 Terhadap Return Saham: Penelaahan Beberapa Sektor Industri. Akuntabilitas: Jurnal Ilmu Akuntansi, 14(2), 269-278.

The Momentum Gap and Return Predictability

The formation period return difference between past winners and losers, which I call the momentum gap, negatively predicts momentum profits. I document this for the U.S. stock market and find consistent results across 21 major international markets. A one-standard-deviation increase in the momentum gap predicts a 1.25$\%$ decrease in the monthly momentum return after controlling for existing predictors. This predictability extends up to 5 years for static momentum portfolios, consistent with time-varying investor biases. Following the simple real-time strategy of investing in momentum only when the momentum gap is below the 80th percentile delivers a Sharpe ratio of 0.78.

Investor sentiment and the time-varying sustainability premium

Studies show the inconclusive results regarding the relation between corporate social and environmental responsibility (CSR and CER) and expected returns. We argue that the reason for these mixed results is that the sustainability premium (i.e., the return difference of high-intensity minus low-intensity CSR/CER firms) is time-varying and correlated with investor sentiment. We find that high-intensity CSR (CER) firms have a monthly excess return that is 0.70 (0.88) p.p. higher following periods of low investor sentiment as compared to periods of high sentiment. Given that standard pricing factors cannot fully explain the abnormal returns caused by investor sentiment on the sustainability premium, we propose a sustainability pricing factor, estimated as the second principal component of portfolios sorted based on environmental and social variables, which corrects this mispricing.

Negative feedback

Negative feedback is an essential constituent of any control system. It is illustrated for the case of an electronic voltage amplifier. Formal definitions are given of positive and negative feedback. Feedback can be used to adjust the amplifier's frequency response. Distortion, meaning generation of new and unwanted frequencies (harmonics, sums, differences), is reduced by a factor equal to the “return difference”.

Performance Of Auto-Callable Reverse Convertibles, Information Disclosure Prescribed By Regulation S-K Change In 2013 Under U.S. Security Act: An Empirical Study

This thesis studies the effect of the estimated value disclosure imposed in 2013 on the realized return of the auto-callable reverse convertibles (ACRCs) in the U.S. retail market. The sample of this study consists of about 3,700 issues of ACRCs during the period from 2011 to 2015, which is collected from the Edgar database of the U.S. Security and Exchange Committee (www.sec.gov). The comparison between product realized return and the return of underlying assets reveals that the ACRCs are underperformed by 5% on average, while further analysis shows that the return difference was broadened after the disclosure regulation. It is found that the statistical attributes of the underlying assets are critical to the product performance while they are hidden by the issuer of ACRCs. The disclosure regulation is presumed to enhance information disclosure and to further protect the investors, but the deteriorated performance of ACRCs indicates a failure of the regulation. To protect the anonymity and confidentiality, the identity of the issuer of ACRCs in our sample is removed without compromising the validity of our research. The original data is available upon request.

Performance Of Auto-Callable Reverse Convertibles, Information Disclosure Prescribed By Regulation S-K Change In 2013 Under U.S. Security Act: An Empirical Study

This thesis studies the effect of the estimated value disclosure imposed in 2013 on the realized return of the auto-callable reverse convertibles (ACRCs) in the U.S. retail market. The sample of this study consists of about 3,700 issues of ACRCs during the period from 2011 to 2015, which is collected from the Edgar database of the U.S. Security and Exchange Committee (www.sec.gov). The comparison between product realized return and the return of underlying assets reveals that the ACRCs are underperformed by 5% on average, while further analysis shows that the return difference was broadened after the disclosure regulation. It is found that the statistical attributes of the underlying assets are critical to the product performance while they are hidden by the issuer of ACRCs. The disclosure regulation is presumed to enhance information disclosure and to further protect the investors, but the deteriorated performance of ACRCs indicates a failure of the regulation. To protect the anonymity and confidentiality, the identity of the issuer of ACRCs in our sample is removed without compromising the validity of our research. The original data is available upon request.

Optimization of Stock Portfolios Using Goal Programming Based on the Kalman-Filter Method

Long-term stock investment development is carried out by means of portfolio optimization. Selection of stocks for portfolios is not only based on high-value stock prices but also takes into account their fluctuations. Estimation of future stock price fluctuations has an indirect impact on future portfolio formation. This research has implemented the Kalman filter method to obtain the best estimation results from various stock prices with a high degree of accuracy. The results are then used to form a stock portfolio on the basis of Goal Programming. This study has compared the optimization results with the real value of stock prices. The results obtained, Kalman filter-based Goal Programming is more effective for predicting future portfolios compared to the Goal Programming method with a return difference of Rp. 178,039,848. This suggests that optimization with the Kalman Filter-based Objective Programming can be used as a tool to determine future stock portfolios.

Time-varying Response Analysis of Spur Gear System

In this paper, a space-driven two-stage spur gear system is taken as the research object, and a 10 DOF dynamic model is established. Considering the high load characteristics of the space drive system and the time-varying stiffness and tooth clearance of the gear system, a nonlinear dynamic response analysis was performed. The characteristics of the vibration acceleration, shock and transmission error of the gear system are studied in this paper. This paper analyzes the relationship between backlash and return difference, and derives the theoretical formula between the two. The time-varying stiffness was corrected to make the theoretical model closer to reality. The research in this paper enriches the study on space drive systems and high load gear systems.

Dynamic Response Analysis of Spur Gear System with Backlash

There are few studies on space-driven gear systems in the existing literature. In this paper, a spacedriven two-stage spur gear system is taken as the research object, and a 10 DOF dynamic model is established. A nonlinear dynamic response analysis was performed. The backlash was introduced into the dynamic model, and the time-varying stiffness was corrected to make the theoretical model closer to reality. By comparing two kinds of dynamic response curves with and without return difference, it was illustrated that the influence of return difference on dynamic transmission error in a gear system. The results obtained in this paper provide a reference and basis for subsequent research.

Risk Factors of Collateralized Loan Obligations and Corporate Bonds

Structured products like collateralized loan obligations (CLOs) tend to offer significantly higher yield spreads than corporate bonds (CBs) with the same rating. At the same time, empirical evidence does not indicate that this higher yield is reduced by higher default losses of CLOs. The evidence thus suggests that CLOs offer higher expected returns compared to CB with similar credit risk. This study aims to analyze whether this return difference is captured by asset pricing factors. We show that market risk is the predominant risk factor for both CBs and CLOs. CLO investors, however, additionally demand a premium for their risk exposure towards systemic risk. This premium is inversely related to the rating class of the CLO.