Explained variance plot. Source: authors (2023).

Explained variance plot. Source: authors (2023).

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Financial bubble prediction has been a significant area of interest in empirical finance, garnering substantial attention in the literature. This study aims to detect and forecast financial bubbles in the Vietnamese stock market from 2001 to 2021. The PSY procedure, which involves a right-tailed unit root test to identify the existence of financial...

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Financial bubble prediction has been a significant area of interest in empirical finance, garnering substantial attention in the literature. This study aimed to detect and forecast financial bubbles in the Vietnamese stock market from 2001 to 2021. The PSY procedure, which involves a right-tailed unit root test to identify the existence of financia...
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... Ultimately, the use of AI-based predictive models allows for the identification of correlations between sentiment shifts and nonlinear price behavior. (Tran et al., 2023) argue that employing deep learning models to capture investor behavior during market crises yields more representative results compared to conventional statistical methods. ...
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In recent years, retail investor participation in Southeast Asian capital markets has surged, contributing to increased market volatility and making sentiment analysis a critical factor in understanding price dynamics. This study investigates the relationship between social media sentiment and stock market fluctuations by focusing on Twitter data during periods of market volatility in Indonesia, Thailand, and Malaysia. The objective is to examine how collective investor emotions, as expressed through social media, correlate with daily stock index movements. Employing an exploratory quantitative approach, the study integrates Natural Language Processing (NLP) methods, both lexicon-based tools such as VADER and advanced transformer-based models like BERT and GPT, to classify over 150,000 tweets into positive, negative, and neutral sentiments. Sentiment scores were then aggregated and statistically tested using Pearson correlation with daily stock index returns, specifically the IDX Composite, SET Index, and FTSE Bursa Malaysia. The findings reveal a significant negative correlation between negative sentiment and market returns, particularly in the IDX Composite (r = -0.61, p < 0.05), indicating that pessimistic sentiment is associated with market downturns. Thailand’s SET Index and Malaysia’s FTSE Index showed moderate to weak negative correlations, with r = -0.43 and r = -0.27, respectively. These results highlight the sensitivity of emerging markets to emotionally driven retail behavior. The study concludes that AI-based sentiment analysis offers a valuable early warning tool for market volatility and can complement traditional financial indicators. It recommends developing AI-based sentiment dashboards and enhancing digital financial literacy to mitigate emotional reactivity among retail investors.
... Οι μέθοδοι μηχανικής μάθησης μπορούν να χειριστούν μεγάλα, πολύπλοκα σύνολα δεδομένων και να αποκαλύψουν κρυφά μοτίβα που μπορεί να χάνουν από τις παραδοσιακές στατιστικές μεθόδους. • Μάθηση χωρίς επίβλεψη: Οι αλγόριθμοι της συγκεκριμένης κατηγορίας δεν απαιτούν δεδομένα με ετικέτα και είναι ιδιαίτερα χρήσιμοι για τον εντοπισμό ανωμαλιών σε οικονομικά δεδομένα (Tran et al. 2023). Τεχνικές όπως η ομαδοποίηση (π.χ. ...
... Εντοπίζοντας ασυνήθιστα πρότυπα στις δραστηριότητες των δεικτών, τις ροές συναλλαγών των εταιριών ή στην κερδοφορία, οι επενδυτές μπορούν να διαφοροποιήσουν τις επενδύσεις απομονώνοντας τα χρηματοοικονομικά οχήματα που εμφανίζουν έντονες διακυμάνσειςανωμαλίες (Koyuncugil and Ozgulbas 2012;Vanini et al. 2023). Για παράδειγμα, κατά τη διάρκεια της χρηματοπιστωτικής κρίσης του 2007-9, τα ιδρύματα που χρησιμοποιούσαν ισχυρά συστήματα διαχείρισης κινδύνου βασιζόμενα σε ανίχνευση ανωμαλιών ήταν σε καλύτερη θέση για να μετριάσουν την επερχόμενη κατάρρευση (Tran et al. 2023). ...
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... Of course, this behavior further increases the price and patterns of the herding behavior of noise traders. Tran et al. (2023) define bubbles that are primarily driven by irrational investor behavior as classical. Ideally, rational arbitrageurs aim to exit the market just before the crash occurs. ...
... The primary focus of numerous studies concerns the identification of bubble conditions and volatility spillovers and undertaking crash forecasts (Lleo and Ziemba 2019;Yousaf and Hassan 2019). Tran et al. (2023) highlight that there is still a lack of a clear-cut definition of a bubble crash in the literature. Sornette (2009) defines crashes based on anomalous price patterns. ...
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... The slow response of housing supply to market demand allows bubbles to grow and potentially burst, causing significant economic disruptions. Recent trends in housing markets in various global cities, marked by substantial price surges amid economic uncertainties, have renewed concerns about forming new bubbles and the effectiveness of existing strategies to address them [5][6][7]. Considering the significant risks associated with housing market bubbles and the limitations of current knowledge and policy tools, accurate prediction and effective management of these bubbles are crucial. 8 ...
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It is known that there is a phenomenon in the economy when the basic value of any tangible or intangible asset differs significantly from its market value, and the growing demand causes an increase in prices. Thus, trading in significant volumes of such assets is carried out at an inflated price, which in turn creates financial bubbles. The theory of efficient markets, present in information sources, states that the available asset prices are always in line with market requirements and take everything into account, but at the same time, it is assumed that market participants act rationally when making their decisions. However, markets are ruled by people, and as sociological studies show, all people are irrational to one degree or another in their actions. To date, there are no clear and effective tools that allow predicting and preventing the formation of financial bubbles with sufficient accuracy, and experts offer expert judgments about the risks of a bubble based on the analysis of financial time series and the comparison of the expected market with the available data of previous crisis situations. The work offers an overview of information sources, which consistently present the essence and prerequisites of the appearance of financial bubbles, the process of their formation, their impact on economic indicators both at the global level and on the economy of individual countries. Also, the considered works describe in detail the behavioral model of the financial bubble, the supply and demand function, the general equation of the asset price, and the dynamics of behavioral contagion of the market population. An overview of the behavioral mathematical model of the financial bubble is presented separately. The article argues the relevance of creating informational methods for forecasting the emergence of financial bubbles, as well as building a model capable of demonstrating trends, not only of ordinary bubbles, but also of serial bubbles. Using the Python programming language, auxiliary libraries and frameworks, with the application of the indicated behavioral model of the financial bubble, data simulation was carried out and a number of interactive visualizations of the process of their formation, development and disappearance were built. Also, the obtained results make it possible to assert that people, even without professional knowledge in the field of information technologies and programming, can create sufficiently productive information systems for analyzing financial market data.
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Стаття є оглядово-інформаційним викладенням матеріалу з використання моделей машинного навчання для прогнозування фінансових показників з можливістю покращення ухвалення рішень з метою формування збалансованого портфеля акцій. Об’єднання глибокого аналізу з машинним навчанням, використовуючи методи лінійної регресії, дерев рішень, випадкових лісів та платформ автоматичного навчання, є потужним інструментом для передбачення ринкових трендів та стратегічних рухів, а також тестування гіпотез. Особлива увага приділяється аналізу ефективності різних методів машинного навчання в умовах невизначеності та турбулентності ринку. Використання моделей штучного інтелекту, дозволяє враховувати залежності у фінансових даних. На основі проведених досліджень визначаються основні напрями подальших дій у цій сфері, включаючи впровадження інформаційних моделей у практичну діяльність фінансових інститутів.
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This study meticulously examines market bubbles within specific sectors of the National Stock Exchange (NSE) over the period from January 2017 to December 2023, employing robust methodologies like RADF, SADF, and GSADF tests. The analysis, centered on 11 sectoral indices, integrates GSADF values with RADF and SADF, offering nuanced perspectives that underscore the sector-specific nature of bubbles. Notably, the study highlights bubble occurrences during the 2020 global crisis due to pandemic, emphasizing their dynamic and diverse manifestations amid the pandemic. Exclusive identification of bubbles in NSE IT, NSE Metal, and NSE Pharma enriches the strategic insights available to investors, facilitating informed decision-making and risk management. The sector-wise approach contributes to a holistic understanding of market dynamics, providing investors with valuable tools to navigate the intricacies of the financial landscape. Future research avenues may delve into regulatory impacts on sector-specific bubbles and explore the interplay between macroeconomic indicators and sectoral bubbles, offering deeper insights into market dynamics.