Browsing by Subject "Mergers and acquisitions"

Now showing 1 - 5 of 5

Open Access
Cournot competition in networked markets
(ACM, 2014) Bimpikis, K.; Ehsani, S.; İlkılıç, Rahmi
The paper considers a model of competition among firms that produce a homogeneous good in a networked environment. A bipartite graph determines which subset of markets a firm can supply to. Firms compete a la Cournot and decide how to allocate their production output to the markets they are directly connected to. We assume that markets have inverse linear demand and firms have quadratic production costs. First, we show that the resulting Cournot game has a unique equilibrium for any given network and provide a characterization of the production quantities at equilibrium. Our results identify a close connection between the equilibrium outcome and supply paths in the underlying network structure. In particular, we show that whether two firms see their output in different markets as strategic substitutes or complements depends critically on the paths between those markets in the line graph induced by the original bipartite network. Armed with a characterization of the equilibrium supply decisions, we explore the effect of changes in the network structure on firms' profits and consumer welfare. First, we study the question of a firm entering a new market. We show that entry may not be beneficial for either the firm or the consumers as such a move affects the entire vector of production quantities. The firm might face a more aggressive competition in its original markets due to its entry to a new market. Moreover, the effect on other firms and consumers also depends on their location in the network. This is in stark contrast with standard results in Cournot oligopoly where entry implies more competition in the market and thus higher consumer welfare. Similarly, the effect of a merger between two firms on profits and overall welfare largely depends on the structure of competition in the original Cournot market. In particular, we show that insights from analyzing mergers in a single market do not carry over in a networked environment. Market concentration indices are insufficient to correctly account for the network effect of a merger and one should not restrict attention to the set of markets that the firms participating in the merger supply to. Finally, we study the operations of a cartel including the entire set of firms. We show that the cartel maximizes its profits by appropriately segmenting the markets among its members so that a firm supplies solely to the ones allocated to it, and we provide an algorithm that computes the optimal production quantities for each firm in the cartel. © 2014 Authors.
Open Access
Decoding strategies at the relay with physical-layer network coding
(Institute of Electrical and Electronics Engineers, 2012) Bhat, U.; Duman, T. M.
A two-way relay channel is considered where two users exchange information via a common relay in two transmission phases using physical-layer network coding (PNC). We consider an optimal decoding strategy at the relay to decode the network coded sequence during the first transmission phase, which is approximately implemented using a list decoding (LD) algorithm. The algorithm jointly decodes the codewords transmitted by the two users and sorts the L most likely pair of sequences in the order of decreasing a-posteriori probabilities, based on which, estimates of the most likely network coded sequences and the decoding results are obtained. Using several examples, it is observed that a lower complexity alternative, that jointly decodes the two transmitted codewords, has a performance similar to the LD based decoding and offers a near-optimal performance in terms of the error rates corresponding to the XOR of the two decoded sequences. To analyze the error rate at the relay, an analytical approximation of the word-error rate using the joint decoding (JD) scheme is evaluated over an AWGN channel using an approach that remains valid for the general case of two users adopting different codebooks and using different power levels. We further extend our study to frequency selective channels where two decoding approaches at the relay are investigated, namely; a trellis based joint channel detector/physical-layer network coded sequence decoder (JCD/PNCD) which is shown to offer a near-optimal performance, and a reduced complexity channel detection based on a linear receiver with minimum mean squared error (MMSE) criterion which is particularly useful where the number of channel taps is large.
Open Access
Inventory performance with pooling: evidence from mergers and acquisitions
(Elsevier, 2015) Çömez-Dolgan, N.; Tanyeri B.
Theoretical studies show that compared to decentralized inventory management, (i) pooling inventories for different demand sources decreases the optimal safety stock, which in turn decreases inventory costs and (ii) the decrease in stock is related to the correlation between the different demand sources and variabilities of demands. Mergers and acquisitions (M&A) provide a business context to investigate the effects of correlation and variability of the merging firms' demands on potential improvements in inventory performance through inventory pooling. While merging firms may not fully centralize their inventory decisions, the coordination of inventory and supply chain decisions may result in synergies. Using firm-level data for 270 same-industry mergers carried out in U.S. between 1981 and 2009, we find that the inventory turnover of bidder and target firms improves (relative to firms in their industry) following the successful completion of mergers. The improvement in turnover is especially pronounced in deals where the demand of bidder and target firms are negatively correlated prior to the merger. Our results provide novel empirical support for the predictions of theoretical models on inventory economies in M&A.
Open Access
Şirketler hukuku düzenlemeleri çerçevesinde yapısal değişikliklerde rekabet yasağı
(2022-12) Akıncı, Dilara
Temelini Anayasa’nın 167.maddesinden alan rekabet yasağı kurumu, 6102 sayılı Türk Ticaret Kanunu (TTK) hükümlerine de konu olmuş ve böylelikle şirketler hukukunda yerini almıştır. Şirket menfaatinin ve dolayısıyla şirket ile hukuki ilişki içerisinde bulunan diğer menfaat sahiplerinin korunmasına hizmet eden rekabet yasağı düzenlemeleri ile kanun koyucu, yönetici veya ortakların şirketi zarara uğratacak iş ve işlemlerden kaçınmasını amaçlamaktadır. Bu kapsamda çalışmamızda ilk olarak rekabet yasağının getiriliş amacı (ratio legis) ve diğer kavramlar ile olan farkları ortaya konmuş daha sonra TTK’daki düzenlemeler şirket türleri bakımından ayrı şekilde incelenmiştir. Her ne kadar yasağın uygulanışı bakımından her şirket türüne ilişkin farklılıklar bulunsa da rekabet yasağına ilişkin düzenlemelerin belirli ilkeler üzerine temellendirildiği görülmektedir. Buna göre rekabet yasağı, emredici nitelikte olmadığından, yasağın kaldırılmasına veya kapsamının değiştirilmesine imkân tanınmıştır. Yine yasağın taraflar arasında akdedilecek bir sözleşme ile düzenlenmesi mümkündür. Ancak yasağın dar yorumlanması esas olduğundan, anayasa madde 48’de düzenlenen çalışma ve sözleşme yapma özgürlüğünün gereğinden fazla sınırlandırılmasını hukuk düzeni himaye etmemektedir. Aynı şekilde sözleşme yoluyla düzenlenen yasaklar sözleşme özgürlüğü sınırlarına tâbidir. Her ne kadar yasak asıl olarak şirketlerin gündelik işlemlerini yürütmesini güvence altına alıyorsa da yapısal değişiklik işlemlerinde de varlığını sürdürmektedir. Bu kapsamda çalışmamızda yapısal değişiklik süreçlerinde yasağın kapsamının ne şekilde değişeceği çeşitli ihtimaller dahilinde ortaya konmaktadır. Nihayetinde yapısal değişiklik süreçlerinde de şirketlerin menfaatinin korunması önem arz ettiğinden, rekabet yasağının bu süreçte şirket menfaatine olan etkisi, birleşme devralma, bölünme ve tür değiştirme işlemleri bağlamında incelenmiştir.
Open Access
SONIC: streaming overlapping community detection
(Springer, 2016) Sarıyüce, A. E.; Gedik, B.; Jacques-Silva, G.; Wu, Kun-Lung; Catalyurek, U.V.
A community within a graph can be broadly defined as a set of vertices that exhibit high cohesiveness (relatively high number of edges within the set) and low conductance (relatively low number of edges leaving the set). Community detection is a fundamental graph processing analytic that can be applied to several application domains, including social networks. In this context, communities are often overlapping, as a person can be involved in more than one community (e.g., friends, and family); and evolving, since the structure of the network changes. We address the problem of streaming overlapping community detection, where the goal is to maintain communities in the presence of streaming updates. This way, the communities can be updated more efficiently. To this end, we introduce SONIC—a find-and-merge type of community detection algorithm that can efficiently handle streaming updates. SONIC first detects when graph updates yield significant community changes. Upon the detection, it updates the communities via an incremental merge procedure. The SONIC algorithm incorporates two additional techniques to speed-up the incremental merge; min-hashing and inverted indexes. Results show that SONIC can provide high quality overlapping communities, while handling streaming updates several orders of magnitude faster than the alternatives performing from-scratch computation.