1 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning: Predicting Stock Market Performance Through Investor's Sentiment Analysis by News Analytics Mohotarema Rashid Department of Information Science, University of North Texas 2 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Abstract Stock Market performance prediction is a complicated task. Because there are no straightforward rules to predict the stock market's performance, market performance is affected by so many variables. Investors' sentiment is one of the variables. This paper aims to capture investors' sentiments by analyzing news headlines. The author use mixed method study to predict the performance of the stock market of NYSE (New York Stock Exchange) In addition, this study explains investors' sentiment through the lens of prospect theory. Keywords: stock market performance prediction, NLP, deep learning, investor's sentiment, machine learning, artificial intelligence, prospect theory 3 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning: Predicting Stock Market Performance Through Investor's Sentiment Analysis by News Analytic Analyzing human psychology is not easy because how people perceive information when it comes to decision-making is challenging. Based on that, scholars have been interested in how people make their decisions. In the era of Machine Learning (ML), Artificial Intelligence (AI), and big data, people are exploiting opportunities to make better decisions that were not common in the early 19s. With the advent of the interdisciplinary field like Information Science (IS), researchers applied information science theory in other domains and vice versa. Since there is no specific area that IS encompasses, it posits a huge opportunity for IS researchers to explore different research areas with great impact. That being said, in a broad sense, IS deals with aspects of processes of the information life cycle. Information Science is at the intersection of people, information, and technology concerned with the body of knowledge needed to understand problems and aims at improving the decisionmaking procedure of both individuals and organizations. The interdisciplinary aspect of information science was addressed by Williams (1998). To solve the problem, like what to do with the information, he mentioned that information science creates a unified place using theories, techniques, and technologies of versatile fields. At the same time, he gave examples of such areas: computer science, library science, management science, and many more. Since information is the product of almost every field, as a convergence point of many disciplines, information science deals with collecting, retrieving, processing, and extracting meaningful ideas from information. The convergence point helps us broaden our view about how information can be obtained and 4 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning processed so that individuals and organizations can benefit from the science that can enable people to make optimal decisions. Bates & Maack (2009) connected three things: technology, human, and information. Being a business major and having experience as a faculty in the business discipline, I was always passionate about combing my business knowledge with technical knowledge. Before pursuing a Ph.D. in IS, I had a minimal background in the technical field. But, since I mentioned that IS is a field where researchers from different fields collaborate, I found a way to combine my knowledge with the IS field. In the era of big data, Machine Learning (ML) and Artificial Intelligence (AI) information are generated every Nano second, which opens the door to extracting meaningful knowledge from that information. The stock market is where scholars from different fields amalgamate, making this domain an interdisciplinary field. Stock market performance prediction through a different kind of information has long been practiced among researchers. But predicting the performance of a complex market like the stock market is difficult because of the unavailability of black-and-white rules. Among the variables that affect stock market performance, some of them can be quantified and some of them cannot be quantified. We can divide the variables broadly into two factors. Earnings, board of structures, and specific news regarding companies are considered the company's internal factors (Jawahar et al., 2020), and macroeconomic environment, government policy, and, most importantly, investors sentiment are regarded as company external factors (AlTamimi et al., 2011). Investors' sentiment is one of the key components that can shape the performance of the stock exchange. Among the variables that affect the performance of the stock exchange, investors' sentiment is crucial, shaping the stock exchange's performance (Sohangir, 2018). 5 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Because investors are the people who ultimately make decisions about buying and selling stocks, which ultimately shape the performance of the share market, investors react to the information they read, hear and share. Since most of the information about companies, markets, and macroeconomic situations is published online and in printed media, investors' sentiments are affected. Lillo et al. (2015) suggested that the literature related to news impact on investors' behavior is not massive. Barber and Odean (2008) found that investors frequently discuss the news published in online and print media, and they concluded that investors' sentiment is spiked by sensitive news about the company. Nofsinger (2001) stated that in USA if a news is published in Wall Street journal both institutional investors and individual investors react to that information. Efficient Market Hypothesis (EMH) developed by Fama (1970) states that the stock price should reflect all the information available. Still, this theory was challenged by Kahneman and Tversky (1979) by saying that in stock price movement, investors' perception of company-specific information does matter. Since investors are not highly rational, quantifying investors' sentiment is challenging. That narrowed my research interest to analyzing investors' behavior through news analytics. Analyzing the stock market through news analytics is not new (Nemes & Kiss, 2021; Khalil & Pipa, 2022; Oncharoen & Vateekul, 2018; Li et al., 2014). As a result, this paper focuses on analyzing investors' sentiment through news headline analytics, so it is imperative to explain what we mean by investors' sentiment. Investor sentiment is not straightforward, and in existing literature, the definition of investor sentiment is rarely addressed. Zhang (2008) came up with an understandable definition of investor sentiment. He argued that investors' sentiment indicates market participants have notions regarding future earnings in terms of some pre-specified standard. That standard reflects the value the investors place on the underlying assets. In traditional 6 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning behavioral finance, the conventional model could not capture how investors' sentiment drives the stock exchange performance (Barberis, 1998). But the model he developed answers the crucial questions about investors' weight on the specific news. Investors show under-reaction to company earnings declarations but over-reaction towards a pool of good and bad information about the company. Guo et al. (2017) state that specific news spreads rapidly with the development of communication methods among investors. Due to the spread of the information, individual investors buying and selling decisions are affected. They concluded that sentiment drives the stock market when many investors' interests align with each other. Due to the availability of unstructured textual, massive data machine-learning techniques come into play. The ML and AI model analyzes stock exchange based on placing past data as input and predicting the future as output. Khalil and Pipa (2022) claim that the news analytics approach is in the initial stage and an underexplored area. Combining deep learning models and Natural language processing can advance this field. With the massive amount of data, this paper's focus is to develop a structured Natural Language Processing (NLP) technique to capture investors sentiment through analysis of news headlines. Problem Statement: Conducting NLP tasks need a massive amount of data to train the model. And sometimes, the word meaning might be changed in terms of the domain. "Underestimate" is a negative word, but in the case of the share market, "underestimated stock" seems a positive word. Agarwal (2022) claimed that the main challenge in the NLP task is to identify and predict the rare and unseen words; for that purpose, domain-specific knowledge is a prerequisite, which demands a domainspecific sentiment index with domain-specific words. Traditional ML models, like word-to-vector and bags of words, suffer from the problem mentioned by Agarwal (2022). 7 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Traditional Techniques like Natural Language Processing Has Shortcomings: Domain-based Word Meanings can be different Traditional model suffers from the wrong prediction of unseen and rare word Research Question The shortcomings of the traditional ML model can be overcome by employing deep learning techniques. Oncharoen & Vateekul (2018) claim that conventional NLP methods, like word embedding, suffer from the problem of sparsity in the dataset. They employed a deep learning model on the dataset of Reuters, Reddit, Intrino and reported that deep learning models like CNN and LSTM give better prediction power. Correia et al. (2022) described the process of deep neural networks producing sentiment and proposed a novel approach like a deep learning-based classification framework for stock market sentiment prediction. They reported the accuracy level on training data as around 73% and on test data as around 69%. Since I intend to develop and apply domain-based sentiment analysis and overcome the shortcomings of the traditional NLP model by employing deep learning techniques that led me to generate the below-mentioned research questions: • How does the news-headlines affect the investors sentiment? • Does domain specific sentiment analysis outperform general sentiment analysis? • And what is the best algorithm for predicting stock market performance? 8 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Hypothesis In combination with the deep learning model, NLP can predict stock market performance with optimal accuracy. Investors sentiment can be captured through news analytic approach. Literature review It's not entirely novel to think about using text analysis to study the financial markets, and sentiment analysis's influence on them is well known. According to a research by Klein and Prestbo (1974), which demonstrates that a negative financial news story can impact the markets. They also concluded that content of the news report and performance of the market are strongly correlated. Engle and Ng (1993) put out the idea of a news impact curve as a way to use news to describe market phenomena. Guo et al. (2017) compared sentiment of stock market on different period in China and he concluded that sentiment data can be a great indicator of performance of stock market. But they concluded that always investors sentiment cannot be a greater indicator of market performance rather it depends on the market specific factors. By developing a novel framework Wuthrich et al. (1998) predicted the performance of stock market through analyzing financial news. They concluded that investors concentrate on the financial stories of the specific company. As a result, it is well accepted that investors pay great deal of attention to the news headlines (Melvin & Yin, 2000). Wang et al. (2020) developed a sentiment analysis to provide insights in implementing effective public health initiatives. Their study data collected from a Chinese social media website and they divided sentiment into positive, 9 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning negative and neutral and extracted the summary of the theme by using TF-IDF (term frequencyinverse document frequency) model. Chan & Chong (2017) extracted insights from unstructured data like textual data and found the trends of financial market. They developed a novel approach called Sentiment Analysis Engine(SAE) based on linguistic analysis. Then extended their model to not only in token or word level but also in phrase level. And their model outperformed the traditional Bag of Words (BoW) model. They concluded that sentiment analysis is helpful to analyze stock market index albeit such sentiments and stock market index are not perfectly correlated. Corriea et al. (2022) mentioned that combination with deep learning and deep learning can give insights in case of extract insights. In this study the authors showed how deep learning reacts to different contexts. They provided a generalized deep learnings classifications model to analyze financial sentiments. In their study Convolutional Neural Network (CNN) outperformed among the several deep learning model and attained accuracy of around 73% on training data and 69% accuracy on test data. Das et al. (2022) stated that the prediction of stock market is a very challenging task because of the heterogeneous components affect the stock market. They predicted the performance of stock market using public sentiment and analyzed those sentiments through Long and Short Term Memory Network (LSTM). They collected data from Newspaper and Facebook and used seven sentiment analysis tools like VADER (Valence Aware Dictionary for Sentiment Reasoning), Logistic Regression, Loughran–McDonald, Henry, TextBlob, Linear SVC (Support Vector Machine), and Stanford, they have concluded that Linear SVC contributed towards a large number of accuracy. 10 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Kalyani et al. (2016) incorporated Efficient Market Hypothesis (EMH) stated by Fama (1970) that market price of the stock should be reflected all the available information in the market. Through their study they tried to assess the relationship among financial news and stock market prediction. They have used three classification models like Naïve Bayes, Random Forest and Support Vector Machine (SVM). And they have concluded that Random Forest and Support Vector Machine attained greater accuracy. Biswas (2020) mentioned that according to financial researchers, news articles, blogs, and stock market predictions are significant themes that influence many businesses' revenues. He used past online news to track the stock market trends by using several machine learning algorithm and concluded that the stock market experts have a big influence on the stock market investors. Schumaker & Chen (2009) analyzed 9211 financial news and stock quotes from S&P 500 for five weeks and predicted discrete numeric prediction through Support Vector Machines. The authors developed a novel system design called AZFinText system design. To analyze the texual data the authors used three Natural Language Processing (NLP) techniques Bag of Words, Named Entities and Noun Phrases. They concluded that in terms of texual representation proper noun scheme outperformed other techniques. Li et al. (2011) focused on the accuracy of the machine learning model by accumulating the information that are latent in market news and stock exchange performance. They used a technique called multi-kernel learning technique to predict the Hong Kong Stock Market. Usmani & Shamsi (2021) developed a survey of the techniques that have been used in financial domain to predict the stock market price. Through their survey framework the authors articulated the pros and cons of the present machine learning models. 11 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Financial sentiment through news headlines is not new in the literatures. In the era of big data and machine learning, an unstructured data like text data posits a huge opportunity for the researchers to exploit the opportunities. As a result, this paper aim is to shed light on the investors sentiment, which ultimately shape the performance of stock exchange. Conceptual Framework Since the problem I have identified that deals with human psychology while making decisions, peoples decisions making behavior and Investors decision making behavior can be explained by Prospect Theory developed by Kahneman & Tversky (1979). This theory deals with explaining people’s decision making under risky circumstances. The theory comes into play when expected utility theory developed by Von Neuman and Morgenstern (1953) could not fully explain the decision making choice of individual. Expected utility theory just showed if there are set of choice for human to make, optimal decision would be that decision which would maximize the satisfaction of the decision maker. Individual choose the decisions by quantifying the outcomes of each decisions by probability of the frequency of that outcome. This theory does not take into account the cognitive limitation of human being (Sebora & Cornwall, 1995). Prospect theory shed light on the irrational part of the human being. The difference between prospect theory and utility theory is that under utility theory individual makes decisions in terms of the final wealth and probability of an outcome where in prospect theory individual makes decisions in terms of the perceived value he/she gives on an outcome. This theory based on three principles. They are: i. Individuals perceived gain and loss depends on his or her reference point 12 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Under this principle how individual makes decision depends on the perception of the individual. For example, On the same course someone is happy with securing D and other student is not happy with securing B. The underlying cause is the reference point. The person who secured D his target was to just pass the course on the other hand the person who secured B his target was to secure A on that particular course. ii. Individual adopts a risk-averse strategy when it comes to perceived gains and a riskseeking strategy when it comes to perceived losses. Under this principle individual underestimate those outcomes of which he is not certain of. And when individual makes decision in terms of profit they will prefer certain profit to more profit with possibility of potential loss. For example, if an investor is given two options: Option 1: gain profit of $10 with no potential loss Option 2: gain profit of $30 with potential loss According to prospect theory individual will prefer option 1 , because in terms perceived gain investor shows risk aversion behavior. But when it comes to perceived loss, an individual behaves in a completely different way. Consider the two options that follow, for instance Option 1: a $10 loss with a guaranteed amount and no potential gain Option 2: Potential gain with infinite loss According to prospect theory, in the aforementioned scenario, the person will exhibit a risktaking attitude and select option 2. iii) individual is very sensitive towards loss 13 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Under this principle individual puts more emotion when he experienced loss. Same amount of loss cannot compensate with same amount of gain. For example, the feeling of loss of $50 cannot compensate the gain of $50. Let’s elaborate this principle with additional example: If Individual is given two options: Option 1: Having $ 100 Option 2: Having $200 at first place then take away $100, and ultimately left with $100 Though the net worth in the above two options are same but individual will prefer option 1. Different fields have used prospect theory. The study of information systems has made great use of it. Prospect theory is used by disciplines that study human psychology, decision-making, and behavior to explain unique behavior. One of the best models for describing the activities of particular decision-makers is prospect theory (Wang, 2021). This theory is well known for predicting future stock market returns and various market phenomena. The expectations of expected utility theory frequently diverge sharply from the prospect theory-captured irrational risk attitudes of individual investors. My research problem is capturing investors' sentiments by evaluating news headlines, and this research demands a theory that can forecast investors' psychology. The prospect theory holds that investors are risk-averse when it comes to possible gain and risk-seekers when it comes to potential loss. So, through my analysis, I hope to demonstrate whether investors are buying safe stocks during bullish market conditions and investing in risky stocks during bearish market conditions. Prospect theory has long been employed in the financial industry to describe how investors behave in the stock market (Barberis, 2013). Payne et al. (1984) used utility theory and prospect theory to analyze the choices made by more than 100 American managers. Their findings align with the principles of prospect theory. 14 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Using various case studies, Lee and Park (2019) assessed user experience and examined the prospect theory's validity. Additionally, their findings are consistent with prospect theory's tenets. Figure 1: Conceptual Framework Prospect theory addresses the loss aversion behavior of investors. Experts of stock market stated that loss aversion have been practicing by investors after pre COVID era. In COVID period investors experienced loss significantly. As a result, through guidelines of the prospect theory I would implement a mixed method study to test the validity of the prospect theory. I would also test whether demographic trends among investors influence the loss aversion among investors. Since prospect theory states that investors make their decisions in terms of their emotional weight given to the specific situation and their perception. So through interviews and semi structured questions, I would try to extract those information, on which specific news investors put more weight and how that affects their buying and selling pattern of stock, which can shape the performance of the stock market. 15 Revisiting Prospect Theory in the Era of Artificial Intelligence and Machine Learning Then I will cross check the findings of qualitative study with the quantitative study. By applying ML and deep learning technique to news headline I would extract meaningful insights and will compare the result and test the validity of the theory, which will lead me to answer my research questions. Conclusion Predicting stock market performance through newspaper headlines has gained attention among researchers. Textual data is unstructured but in the era of AI, ML, big data it posits huge opportunity for the researchers to exploit those textual data through AI, ML techniques. A theoretical integration with the AI, ML can give us greater insight regarding a volatile market like stock market. As a result, this study use prospect theory as a guideline which prescribes investors decision making pattern certain circumstances. 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