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Mining sequential patterns in large databases has become an important data mining task with broad applications, such as business analysis, web mining, security, and bio‐sequences analysis. The purpose of this paper is to propose the notion of condensed frequent sequential pattern base (SP base) with guaranteed maximal error bound.

A subset of frequent sequential patterns is computed, and then used to approximate the supports of arbitrary frequent sequential patterns with guaranteed maximal error bound, because in many applications it is sufficient to generate only frequent sequential patterns with support frequency in close‐enough approximation instead of in full precision.

The concept of condensed frequent SP base is introduced, and an efficient algorithm for mining condensed SP bases is developed.

A condensed frequent SP base can significantly reduce the set of sequential patterns that need to be mined, stored, and analyzed, while providing guaranteed error bound for frequencies of sequential patterns not in the base.

A much smaller base of patterns can help users to comprehend the mining results. Computing a much smaller pattern base also leads to better efficiency.

The paper shows that by adopting a novel pruning technology, the algorithm out‐performs the previous work by one order of magnitude.

In this study, the authors investigate methods of sequential analysis to test prospectively for the existence of a unit root against stationary or explosive states in a p-th order autoregressive (AR) process monitored over time. Our sequential sampling schemes use stopping times based on the observed Fisher information of a local-to-unity parameter. In contrast to the Dickey–Fuller (DF) test statistic, the sequential test statistic has asymptotic normality. The authors derive the joint limit of the test statistic and the stopping time, which can be characterized using a 3/2-dimensional Bessel process driven by a time-changed Brownian motion. The authors obtain their limiting joint Laplace transform and density function under the null and local alternatives. In addition, simulations are conducted to show that the theoretical results are valid.

The online crowdsourcing has been widely applied in the practice. The purpose of this paper is to investigate the all-pay auction contest in crowdsourcing, wherein a seeker posts a task online and the solvers decide whether to participate in the contest and in what extent to spend efforts on their submissions.

The authors specifically consider two classic contest formats: simultaneous contest and sequential contest, depending on whether the solver can observe the prior solvers’ submissions before making her own effort investment decision or not. They derive both seeker’s and solver’s equilibrium decisions and payoffs under different contest formats, and show that they vary significantly according to the number and the average skill level of solvers.

The results show that a solver would always invest more on her submission under simultaneous contest than under sequential contest, as she cannot confirm how other solvers’ submissions would be. This subsequently intensifies the market competition and brings down a solver’s average payoff under simultaneous contest. Although the simultaneous contest gives rise to a higher expected highest quality of all submissions, it also requires the seeker to spend more search cost to identify the best submission. Therefore, when the number of solvers is high or the average skill level is low, the seeker prefers sequential contest to simultaneous contest. The results also show an analogous preference over two formats for the platform.

This paper investigates two formats of all-pay auction contest in crowdsourcing and evaluates them from the perspective of solvers, seekers and platforms, respectively. The research offers many interesting insights which do not only explain the incentive mechanisms for solvers under different contest formats, but also make meaningful contributions to the seeker’s or the platform’s adoption strategies between two alternative contest formats in crowdsourcing practice.

The purpose of this paper is to detect different behavioral groups and the dominant patterns of customer shifts between segments of different values over time.

A new hybrid methodology is presented based on clustering techniques and mining top-k and distinguishing sequential rules. This methodology is implemented on the data of 14,772 subscribers of a mobile phone operator in Tehran, the capital of Iran. The main data include the call detail records and event detail records data that was acquired from the IT department of this operator.

Seven different behavioral groups of customer shifts were identified. These groups and the corresponding top-k rules represent the dominant patterns of customer behavior. The results also explain the relation of customer switching behavior and segment instability, which is an open problem.

The findings can be helpful to improve marketing strategies and decision making and for prediction purposes. The obtained rules are relatively easy to interpret and use; this can strengthen the practicality of results.

A new hybrid methodology is proposed that systematically extracts the dominant patterns of customer shifts. This paper also offers a new definition and framework for discovering distinguishing sequential rules. Comparing with Markov chain models, this study captures the customer switching behavior in different levels of value through interpretable sequential rules. This is the first study that uses sequential and distinguishing rules in this domain.

This paper seeks to challenge the traditional wisdom that sheds light upon sequential entry modes in developed countries by exploring the dynamic entry mode choice in sequential foreign direct investment (FDI) in emerging economies.

A review of the literature on the entry mode choice is undertaken. Based on analysing two related theories consisting of the knowledge‐based theory of the firm and organizational learning theory, entry mode choices in sequential FDI in emerging economies are investigated using both an internationalisation process model and the capability‐developing perspective, and exclusive propositions are put forward accordingly. Then, these propositions are tested on the context of China with the methodology of paired‐samples t‐tests.

Based on macro‐level longitudinal data in China from 1979 to 2005, the choice of entry mode in sequential FDI in emerging economies is inconsistent with the capability‐developing theory of the firm, but is consistent with the international process model.

This study provides four practical implications. First, managers intending to invest abroad need to consider the cost and return of a specific entry mode. Second, knowledge about host markets has a more important effect on entry mode choice in emerging markets than MNCs' internal organizational capabilities. Third, MNCs adopt sequential investment in emerging economies, in which they adopt joint ventures in earlier entries and then shift to green‐field investment in later entries. Fourth, experiential learning, which consists of learning about host markets and local partners' skills, is emphasized in sequentially entering emerging markets.

This paper expands the research scope of previous studies that either explore a static choice of entry mode in foreign markets or only examine the entry mode choice in sequential FDI in developed countries. Taking into consideration the dynamic choice of entry modes, the paper studies sequential FDI in emerging economies, which throws light upon theoretical analysis of sequential FDI in China, and which has practical implications for foreign firms that are interested in China and planning to enter China's markets.

Purpose – Land assembly can mitigate the negative environmental impacts of land fragmentation on urban areas, agriculture, and wildlife. However, the assembler faces several obstacles including transactions costs and the strategic bargaining behavior of landowners. The purpose of this chapter is to examine how the order of bargaining and the nature of contracts may impact the land assembler's problem.

Methodology – We develop theoretical predictions of subjects' behavior and compare these to behavior in a laboratory land-assembly game with monetary incentives.

Findings – Sellers bargain more aggressively when bargaining is sequential compared to simultaneous. Noncontingent contracts increase bargaining delay and the likelihood of failed agreements. Buyers and sellers act more aggressively when there are multiple bargaining periods, leading to significant bargaining delay. When a seller has an earnings advantage in the laboratory, it is the first seller to bargain in noncontingent contract treatments. In sequential bargaining treatments, most sellers preferred to be the first seller to bargain.

Research limitations – Our laboratory experiments involved only two sellers, complete information, and costless delay. Land assembly in the field may involve many sellers, incomplete information, and costly delay.

Practical implications – Some of our results contradict conventional wisdom and a common result from the land-assembly literature that it is advantageous to be the last seller to bargain, a so-called “holdout.” Our results also imply that fully overcoming the holdout problem may require subsidies or compulsory acquisition.

Originality – This chapter is one of the first to experimentally investigate the land-assembly problem, and the first to specifically examine the role of bargaining order and contract type.

Massively parallel desktop computing capabilities now well within the reach of individual academics modify the environment for posterior simulation in fundamental and potentially quite advantageous ways. But to fully exploit these benefits algorithms that conform to parallel computing environments are needed. This paper presents a sequential posterior simulator designed to operate efficiently in this context. The simulator makes fewer analytical and programming demands on investigators, and is faster, more reliable, and more complete than conventional posterior simulators. The paper extends existing sequential Monte Carlo methods and theory to provide a thorough and practical foundation for sequential posterior simulation that is well suited to massively parallel computing environments. It provides detailed recommendations on implementation, yielding an algorithm that requires only code for simulation from the prior and evaluation of prior and data densities and works well in a variety of applications representative of serious empirical work in economics and finance. The algorithm facilitates Bayesian model comparison by producing marginal likelihood approximations of unprecedented accuracy as an incidental by-product, is robust to pathological posterior distributions, and provides estimates of numerical standard error and relative numerical efficiency intrinsically. The paper concludes with an application that illustrates the potential of these simulators for applied Bayesian inference.

The purpose of this paper is to extend two‐dimensional sequential uniform design and present three‐dimensional sequential uniform design which can optimize the problem of determining the extreme value of three‐factor polynomial.

Since there are limitations in two‐dimensional sequential uniform design, three‐dimensional sequential uniform design introduced in this paper is to arrange the experimental points by U₉(9³) uniform design table and to determine the maximum of the experimental values according to the demand. It is proven that the convergence of the experimental central point's sequence and that it can optimize the problem of determining the extreme value of no‐cross term quadratic polynomial monotone function class and the corresponding conditions are also proven. Taking the no‐cross term quadratic polynomial monotone function as an example, the superiority of it is testified.

Three‐dimensional sequential uniform design can optimize the problem of determining the extreme value of three‐factor polynomial. It can get higher precision and better convergence but do fewer experiments than general uniform design.

A very effective method in resolving the problem of selecting optimum on multi‐dimensional space.

A new method of three‐dimensional sequential uniform design which can get higher precision and better convergence is presented.

This paper aims to study the sampling methods (or design of experiments) which have a large influence on the performance of the surrogate model. To improve the adaptability of modelling, a new sequential sampling method termed as sequential Chebyshev sampling method (SCSM) is proposed in this study.

The high-order polynomials are used to construct the global surrogated model, which retains the advantages of the traditional low-order polynomial models while overcoming their disadvantage in accuracy. First, the zeros of Chebyshev polynomials with the highest allowable order will be used as sampling candidates to improve the stability and accuracy of the high-order polynomial model. In the second step, some initial sampling points will be selected from the candidates by using a coordinate alternation algorithm, which keeps the initial sampling set uniformly distributed. Third, a fast sequential sampling scheme based on the space-filling principle is developed to collect more samples from the candidates, and the order of polynomial model is also updated in this procedure. The final surrogate model will be determined as the polynomial that has the largest adjusted R-square after the sequential sampling is terminated.

The SCSM has better performance in efficiency, accuracy and stability compared with several popular sequential sampling methods, e.g. LOLA-Voronoi algorithm and global Monte Carlo method from the SED toolbox, and the Halton sequence.

The SCSM has good performance in building the high-order surrogate model, including the high stability and accuracy, which may save a large amount of cost in solving complicated engineering design or optimisation problems.

Is non‐sequential internationalization process solely technology enabled or a product of mutually interdependent forces? This paper aims to show that even though the sequential approach in the process model is intuitively appealing, not all firms follow such a path. Hence, integrated framework to explain how the international market entry process has changed with respect to the sequential approach is presented.

The data banks of the Swedish Trade Council and the Chambers of Commerce are used to identify small and medium‐sized enterprises (SMEs) with between 50 and 250 employees (in compliance with European Union's definition of SMEs). Data are collected through the use of questionnaires and in‐depth interviews from 60 Swedish SMEs operating in other countries and foreign SMEs operating in Sweden that tends not to develop in incremental stages with respect to their international.

Some of the findings are: that the sequential model is by no means reflective of, or appropriate for all firms' approaches to international business; the usefulness gained by using an international network approach to study the international activity of a firm; and the interplay between the identified driving forces behind a non‐sequential internationalization process.

Even though market entry patterns of firms investigated demonstrate a non‐sequential internationalization process, they are still within the general theoretical framework where the basic assumption of the sequential internationalization model can maintain its validity. Firms are indeed exposed to irrecoverable transaction costs that hamper their behaviours and complicate export supply responses in international markets. However, the magnitude of the costs and speed of internationalization is dependent on the ability of the firms to take advantage of the enablers of non‐sequential internationalization pattern. This is particularly important for firms to and from developing countries and emerging markets and their propensities to succeed in their internationalization endeavours.

Knowledge acquired from the empirical study of firms that tend not to develop in incremental stages with respect to their international activities, and therefore start international activities by entering very distant markets and multiple countries right from birth without prior experience, is used to develop an integrated framework which aptly depicts that non‐sequential internationalization process is not solely enabled by technology, as commonly envisaged in literature, but a product of mutually interdependent forces. Consequently, this study provides a holistic view on the driving forces behind the rapid internationalization process encountered by many SMEs today.