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In this paper, we analyze the trading patterns of investors around the bubble events selected for stocks traded in Korean Stock Market from 1999 to 2013, whose holding period returns exceed 200% for 250 trading days prior to the event and then drop subsequently below -50% thereafter for the next 250 trading days. We examine whether individual investors, commonly known as noise traders, drive the bubbles, and whether institutional investors and foreign investors, known as informed traders, take an arbitrage position to shrink the pricing errors or ride the bubbles to maximize their profits. We also examine whether individual investors suffer losses due to their disposition effect even after the bubble bursts.

Major findings of this paper are as follows : First, we find that individual investors are actually shown to drive the bubbles in our full sample, whereas the burst of the bubbles are largely driven by institutional investors and foreign investors. In particular, it is shown for large-cap stocks that foreign investors take the lead in raising the price at an early stage of the bubbles and then institutional investors follow them until the bubble peak point. Second, for mid-cap and large-cap stocks, institutional investors are found to ride the bubbles from about 75 days prior to the bubble peak point, when foreign investors reverse their trades and start selling to realize profits. Such bubble riding behavior of institutional investors is consistent with the synchronization risk model of Abreu and Brunnermeier (2002, 2003), where it is optimal for informed traders to ride the bubbles until all of informed traders start selling at the bubble peak point. Third, individual investors are found to suffer losses as they keep buying the bubble stocks even after the bubble bursts due to their disposition effect.

This paper attempts to provide novel approaches and tools for the analysis and measurement of stock bubbles.

The study is based on the perspective of a generalized virtual economy and the circulation process of accumulation strengthening and exclusion in the stock noise and is based on the symmetric chain model of the evolutionary game of combination of stock markets. Based on the stable ratio of the rational and irrational investors and the asymptotically stable strategy of the model in the two cases, the paper uses the improved classic model of noise trading (DSSW) to calculate the irrational bubbles on the Shanghai stock market.

The paper shows that the more irrational investors are, the higher the irrational bubbles are.

The method exposed in the paper can be used to study the formation mechanism of the stock market bubble, to analyze the impact of investors' behaviours, to measure the size of irrational bubbles and to put forward some reasonable policy recommendations and preventive measures.

The paper succeeds in pointing out a new stock market's irrational bubble calculation model on the basis of evolutionary game chain structure, and thus measures the size of the Shanghai stock market bubble and makes some tentative research and discussion about the evolution law of the stock market's irrational bubble.

The paper aims at studying numerically a vapour bubble growth in uniformly superheated liquid.

Time dependent mathematical and numerical models are developed. Based on the Stefan boundary condition, the rate of heat transfer at the vapour‐liquid interface and the rate of bubble growth are calculated.

It is found that, at the initial stage of bubble growth, both the growth rate and the mean Nusselt number at bubble interface have the maximum values, then they decrease with time; the rate of bubble growth also has a significant effect on bubble deformation; the growth tends to keep the bubble at its initial shape. In addition, the growth and deformation of a vapour bubble have much influence on temperature propagation in the vicinity of the bubble‐liquid interface; the temperature wake at the rear of the bubble occurs at high Reynolds number but does not appear at low Reynolds number.

The paper is based on the authors' original work, focusing on the behaviour of a vapour bubble in uniformly superheated liquid–an issue of importance in the field of boiling and two phase flow.

Cavitation bubbles cannot be avoided in the hydraulic system. Because of instability of flow and variation of water pressure, the jet often occurs in a bubble collapse. This study aims to accurately predict the shape, velocity and time of the resulting jet, so as to inhibit cavitation erosion.

In the study, a theoretical model of cavitation bubbles in the water has been developed by applying a periodic water film pressure into the Rayleigh–Plesset equation. A fourth-order in time Runge–Kutta scheme is used to obtain an accurate computation of the bubble dynamic characteristics. The behavior of the proposed theory is further simulated in a high-speed photography experiment by using a cavitation bubble test rig. The evolution with time of cavitation bubbles is further obtained.

A comparison with the available experimental results reveals that the bubble evolution with time has a duration of about 0.3T0, that well predicts the expanding and compressing process of cavitation bubbles. The results also show that the initial bubble radius in the water influences the moving velocity of the bubble wall, whereas the perturbation frequency of the water pressure has less effect on the velocity of the bubble wall.

A theoretical model well predicts dynamic characteristics of cavitation bubbles. The bubble evolution with time has a duration of about 0.3T0, Initial bubble radius influences the velocity of bubble wall. Perturbation frequency has less effect on the velocity of bubble wall.

This paper aims to carry out numerical study on growth of a single bubble from a curved hydrophilic surface, in nucleate pool boiling (NPB). The boiling performance associated with NPB on a curved surface has been analyzed in contrast to a plane surface.

Commercial software ANSYS Fluent 2021 R1 has been used with its built-in feature of interface tracking based on volume of fluid method. For water as the working fluid, the effect of microlayer evaporation underneath the bubble base has been included with the help of user-defined function. The phase change behavior at the interface of vapor bubble has been modeled by using “saturated-interface-volume” phase change model.

An interesting outcome of the present study is that the bubble departure gets delayed with increase in curvature of the heating surface. Wall heat flux is found to be higher for a curved surface as compared to a plane surface. Effect of wettability on the time for bubble growth is relatively more for the curved surface as compared to that for a plane surface.

Effect of surface curvature has been investigated on bubble dynamics and also on temporal variation of heat flux. In addition, the impact of surface wettability along with the surface curvature has also been analyzed on bubble morphology and spatial variation of heat flux. Furthermore, the influence of wall superheat on the bubble growth and also the wall heat flux has been studied for fixed angle of contact and varying curvature.

The consumption of bubble tea is a huge phenomenon in Southeast Asia, and many bubble tea stores have been decorated uniquely in an attempt to attract more consumers. Hence, the purpose of this study is to investigate the influence of servicescape on experiential value and its influence on consumers' responses (i.e. eWOM, revisit intentions and willingness to pay a price premium) based on the Stimulus-Organism-Response framework.

This research project gathered survey data from 289 consumers of bubble tea. The collected data underwent analysis employing a statistical technique known as partial least squares structural equation modelling to examine and understand the relationships between different variables within the dataset, offering insights into consumer behaviour and preferences regarding bubble tea consumption.

The results show that factors such as facility aesthetics, seating comfort and cleanliness positively affect experiential value. However, layout accessibility and signs and symbols do not affect experiential value. In addition, experiential value positively affects eWOM, revisit intentions and willingness to pay a price premium.

The importance of servicescape in physical stores within the restaurant setting has been extensively documented in existing literature. However, there is a notable lack of research addressing the influence of servicescape on consumer responses, particularly within the bubble tea context. This study stands out as one of the few endeavours to examine the impacts of servicescape on consumer responses within the bubble tea industry.

This study aims to explore a novel framework for housing price bubbles in the Turkish economy during the pandemic. It examines the probability of housing bubble formation relative to the pre-pandemic period and identifies possible determinants of housing bubbles in the Turkish economy.

In this study, a two-stage novel estimation method is applied. In the first stage, bubble periods are identified through the right-tailed supremum augmented Dickey–Fuller test. In the second stage, the determinants of these bubbles are identified, and the housing bubble determinants during the COVID-19 pandemic are compared to the pre-pandemic period.

The findings indicate that there is an asset price bubble in the housing market during the pandemic period. Furthermore, mortgage credit expansion, mortgage credit rates and the depreciation of the Turkish Lira against the USD could increase housing bubble formation. However, housing sector sales to foreign investors do not contribute to housing bubble formation during the pandemic in the Turkish housing market.

To the best of the author’s knowledge, this is the first study to address the relative determinants of housing bubbles in an emerging market context during the pandemic.

The recent Russia–Ukraine conflict highlights the geopolitical importance of natural gas, especially in Europe. In this light, this study examines the impact of the Russia–Ukraine conflict on the spread of price bubbles from European natural gas to international energy prices.

The Generalized Supremum Augmented Dickey-Fuller (GSADF) test is employed to detect the occurrence of price bubble episodes while the Dynamic Logit Model is used to examine price bubble contagion between the two markets. Further, a tri-variate VAR model is used to examine the determinants of the price bubble.

The findings reveal multiple bubble episodes in both European natural gas and international energy prices. Further, evidence of bilateral contagion between European natural gas and the international energy market is found. In addition, the Russia–Ukraine conflict triggers price bubble episodes in both markets. Finally, a counterfactual analysis suggests that the conflict increases the bubble contagion from the European natural gas market to the international energy market by about 40%. These findings imply that the Russia–Ukraine conflict is a significant driver of high upside risks to bubble occurrence and subsequent contagion to both European natural gas and international energy prices.

To the best of our knowledge, this study contributes new empirical evidence that the Russian–Ukrainian conflict significantly impacts the spread of price bubbles from the European natural gas market to international energy markets.

This chapter presents several approaches for identifying and dating the speculative bubble on real estate market. Using the real estate price index (IPAI), statistical and structural approaches were combined in order to detect the existence of a bubble on the Moroccan real estate market. The results obtained affirm that the Moroccan real estate market experienced a speculative bubble during the period 2006–2008 explained mainly by the boom of credit during the same period. The use of the Markov switching model affirmed that the speculative bubble on Morocco is cyclic and consequently corroborates the critic formulated by Evans (1991) concerning the traditional approaches for the detection of financial bubbles. Thus, the analysis of the series of the bubble, extracted using the Kalman filter, affirms the existence of two regimes, namely an explosive regime and a normal regime. The first regime describes the periods of explosion of the bubble and lasts for about 9 quarters, while the second, lasting for 14 quarters, describes the periods of return to the average cycle.

The ups and downs of the stock markets are consistently in the news. All things considered, there's no end to reporting the trajectory of volatility. Wide value changes in stock prices are a daily event in any stock market as speculators respond to monetary, business, and political situations. The main question is − did the Indian stock market develop a speculative bubble during the time of the US subprime crisis? Also, in terms of knowledge gained for an investor or a policy maker, we ask the following question: As to what extent are speculative bubbles predictable during a financial crisis? Knowledge gained by investors is also a part and parcel of an applied knowledge economy in a broader dimension.

In this chapter, the authors use a speculative bubble tracker, based on a Wiener stochastic process, to check for the existence of speculative bubbles during the 2008–2009 US subprime crisis. The data used in the study are daily SENSEX values (i.e., combination of stock prices of 30 well-established, most actively traded stocks of financially sound companies listed in the Bombay Stock Exchange) for the period between December 2007 and December 2009. Using such forms of daily data, the authors trace out the price movements using a Brownian motion equation and hence, try to correlate the stock price fluctuations with fluctuations in the crisis index (as put together by the authors) in the Indian context. Interestingly, for India, such a speculative bubble was prevalent during the time period considered pertaining to the 2008 US subprime crisis.

Summing up, the implication in terms of knowledge gained is particularly of interest for the portfolio managers who are engaged in devising diversification strategies for their portfolios.