A Quantitative Study of Teacher Perceptions of Professional Learning Communities' Context, Process, and Content Daniel R. Johnson Seton Hall University and date this document only when revisions have been completed. Please return this form to the Office of Graduate Studies Massively Multiplayer Online Games (MMOGs) routinely attract millions of players but little empirical data is available to assess their players’ social experiences. In this paper, we use longitudinal data collected directly from the game to examine play and grouping patterns in one of the largest MMOGs: World of Warcraft. Our observations · The third and final existing study to be outlined is the study, “Internet dating: a British survey” conducted by Barrie Gunter of University of Leicester. This study aims to examine the growing phenomenon of online dating and was widespread in nature, surveying over 3, participants residing in the UK
Landmark study on 11, couples pinpoints what dating apps get so wrong
Applied Network Science volume 4Article number: Cite this article. Metrics details. Cryptocurrencies as a new way of transferring assets and securing financial transactions have gained popularity in recent years. Transactions in cryptocurrencies are publicly available, hence, statistical studies on different aspects of these currencies are possible. However, previous statistical analysis on cryptocurrencies transactions have been very limited and mostly devoted to Bitcoin, with no comprehensive comparison between these currencies.
In this study, we intend to compare the transaction graph of Bitcoin, Ethereum, Litecoin, Dash, and Z-Cash, with respect to the dynamics of their transaction graphs over time, and discuss their properties. In particular, we observed that the growth rate of the nodes and edges of the transaction graphs, and the density of these graphs, are closely related to the price of these currencies.
We also found that the transaction graph of these currencies is non-assortative, i. addresses do not tend for transact with a particular type of addresses of higher or lower degree, and the degree sequence of their transaction graph follows the power law distribution. Cryptocurrencies have made it possible for a financial system to perform transactions without the need for a centralized authority while keeping the transaction details and money generation clear and publicly available.
All transaction information of a cryptocurrency is usually stored in a distributed public ledger, quantitative study on online dating dynamics blockchain. The tasks of recording, updating, and maintaining the blockchain is the responsibility of network users for each coin, whose identities are unknown, and rewards have been created to provide them with sufficient incentives to do so, making the network up and running.
Although the system is running by anonymous people, due to computational infeasibility of forging digital signatures and security of cryptography algorithms, transaction alteration is almost impossible.
This level of security is guaranteed by cryptographic algorithms, and as long as these algorithms are secure, cryptocurrencies integrity is protected. Bitcoin is the first cryptocurrency created by an anonymous person or group of people by the nickname Satoshi Nakamoto, which established a decentralized money transfer system using blockchain Nakamoto Subsequently, other cryptocurrencies, which are usually referred to as altcoins, were created by adding more capabilities and offering alternative design criteria.
Ethereum was introduced by Vitalik Buterin in and is the first blockchain-based distributed computing platform to consider the concept of exe- cutable smart contracts Buterin It is one of the most influential and widely-used cryptocurrencies introduced after Bitcoin, quantitative study on online dating dynamics. Litecoin is also one of the earliest cryptocurrencies that is technically very similar to Bitcoin and has only slight differences with it Litecoin For example, Litecoin uses the Scrypt hash function instead of SHA for proof of work, and records transactions in the blockchain four times faster than Bitcoin.
Litecoin is created as a hard fork of Bitcoin, and has a separate blockchain. Dash is another cryptocurrency which is quite similar to Bitcoin and uses the X11 hashing algorithm for proof of work Duffield and Diaz Similar to Litecoin, Dash quantitative study on online dating dynamics a separate blockchain, with transactions speed 4 times faster than Bitcoin.
Z-Cash is a highly secure cryptocurrency that uses zero-knowledge proofs, as a result of which privacy and anonymity of users is significantly enhanced Hopwood et al. In all of the mentioned cryptocurrencies, the ability to transfer money is the basic and common core capability. Using the blockchain data of each of these currencies, the transactions in which they occur can be accessed. As a result, it is possible to analyze transactions in these currencies from different aspects and perform a variety of statistical analyses on them.
In particular, it is possible to examine a real network of financial transactions for each cryptocurrency. In this paper, the financial exchange network of the five aforementioned cryptocurrencies has been studied and several statistical metrics and network measures are calculated, and their meanings are discussed. From a perspective, this financial exchange network can be seen as a social network, quantitative study on online dating dynamics.
In social networks, nodes are individuals, and the edges between them can be friendships or other social relationships. In the transaction graph of a cryptocurrency, vertices are accounts or addresses in the currency network, and the edges between them are transactions between those accounts. Since these accounts have hidden identities, they do not represent the true identities of individuals.
Note that a person can create multiple accounts, and it is almost impossible to link these accounts, and detect that they belong to the same individual. There are graph analytics methods and heuristics to link some of the accounts Nickbut since these techniques are prone to errors and cannot detect all related accounts, we do not use any quantitative study on online dating dynamics these methods for linking accounts and merging their corresponding nodes in the transaction graph.
Our contributions can be summarized as follows:. We compare the structural properties of the transaction graphs of five widely-used cryptocurrencies. We discuss the relation between the transaction graph properties with technical aspects and historical events of each coin. We investigate the evolution of the transaction graph over time and quantitative study on online dating dynamics the effect of supply and demand, and price of each coin on the transaction graph.
Various studies have been conducted on cryptocurrency transaction networks from different perspectives. Among these studies, there is no comprehensive review, and most of them have focused on one or two specific coins, especially Bitcoin and Ethereum, and used outdated blockchain data which does not cover recent developments in the field.
In most of these studies the transaction graph is investigated statically and its dynamics and evolution over time are not considered. We have categorized related work by the cryptocurrencies they have reviewed:. Ron and Shamir inanalyzed the bitcoin transaction graph statically. In another study on Bitcoin, Maesa et al.
They analyzed the distances between nodes and studied graph metrics such as density and phenomena like the rich-get-richer phenomenon Di Francesco Maesa et al.
But these studies are only limited to Bitcoin, and with modern wallets and the advent of mixers Mixing servicethe deanonymization heuristic has become ineffective.
In another related work by Fleder et al. Their analysis and calculations on the transaction graph is limited, and their deanonymization heuristic is no longer valid due to the existence of mixers. Kondor et al. also conducted a study on the Bitcoin transaction graph, which examined how the Bitcoin transaction graph evolved, quantitative study on online dating dynamics, but their study is limited to Bitcoin Kondor et al.
In a study by Chen et al. They did not examine the money flow graph dynamically and also their study is limited to a few metrics. In another study by Guo et al. However, this study only deals with a small part of the blockchain at two specific time spots and is not showing the dynamics of the graph over time Guo et al.
Liang et al. inhave compared the transaction graphs of Bitcoin, Ethereum and Namecoin. Currently, Namecoin is no longer active and it is not in the list of top coins according to their market capitalization CoinMarketCap Furthermore, their study is not as comprehensive as ours and they focused on a few metrics and a limited quantitative study on online dating dynamics of cryptocurrencies.
The data used in this quantitative study on online dating dynamics were obtained directly from the blockchain of the cryptocurrencies. There are several ways to get these information, and we used two different methods for data collection. For Bitcoin, Ethereum, Litecoin, and Dash, we obtained blockchain data from their peer-to-peer network using their client software. These data are stored in binary format and needed to be converted into human-readable formats such as comma-separated values CSV for further analysis.
These binary data can be converted by parsers which output several large CSV files. These files contain each transaction details including the timestamp, the number of inputs and outputs of the transaction, the incoming and outgoing addresses, and other related information which is stored in the blockchain.
We used Ethereum ETL for EthereumRusty Blockparser for Litecoin RustyBlockparser a modified version of bitcoin core for Bitcoin citebitcoinparser We also made a custom parser for parsing Dash blockchain. To build the transaction graph, we need database operations like Join and Select. Due to the high volume of data, we used Apache Sparkwhich is one of the most well-known big data processing tools, to perform these operations ApacheSpark It has a programming interface called PySpark for Python language that can optimize SQL statements runs on bulk data PySpark To obtain Z-Cash blocks, we used JSON API of SoChain SoChainan online blockchain explorer, which provided the information of all blocks in JSON format and then the transaction graph was constructed SoChain The blockchain structure for each of these cryptocurrencies is different, but some are very similar.
For example, the Bitcoin and Litecoin blockchains are very similar, but the Ethereum blockchain has a completely different structure because of its nature and sophistication. But in all of them, the transaction information is contained within the blocks. In each block, a certain number of transactions can be placed. In general, blockchains can be divided into two categories: UTXO Unspent transaction output -based and account-based. In the UTXO-based blockchains, each transaction input is linked to an output of a previous transaction.
In other words, current transactions in a block are spending the outputs of previous transactions and generating new outputs to be spent in subsequent transactions.
In the outputs of the transactions, quantitative study on online dating dynamics, the addresses to which the output values belong are placed. But in the account-based blockchains, the addresses of the incoming and outgoing accounts are explicitly stated. The blockchain of Bitcoin, Litecoin, Z-Cash, and Dash use UTXO-based output types, and each transaction contains several inputs and outputs. But in Ethereum, whose blockchain is account-based, each transaction has quantitative study on online dating dynamics one input and one output.
In a transaction graph, nodes are accounts addresses, and the edges are the transactions between these accounts.
In this study, we considere a transaction graph as an unweighted undirected graph, but in some analyses, we use a directed version of that graph. Given that each block of the blockchain has a timestamp, we have divided the timeline into monthly intervals and created a transaction graph for each month that only includes the transactions in the blocks of that month.
To make a transaction graph from a set of quantitative study on online dating dynamics, we place one edge from each input address and to each output address in transactions in the graph.
For Coinbase transactions, that include the block generation reward given to the miners and the inputs do not refer to a previous transaction outputs, we considered a supernode as its input and one edge of that supernode to each miner address. For example, in Fig. Generation of a transaction graph. a An example of a transaction with 3 Inputs and 2 Outputs. b Transaction graph based on the transaction in Fig. where V i is the set of nodes of MTG i, quantitative study on online dating dynamics.
where E i is the set of edges of MTG i. There are various metrics for quantitative comparison between transaction graphs of different cryptocurrencies. As mentioned earlier, the transaction graph can be viewed as a social network graph, and all metrics that can be calculated on social networks can also be studied for the transaction graph, quantitative study on online dating dynamics.
We use the most common metrics that are meaningful in the context of transaction graphs and has a relation with technical details and historical events in the timeline of each coin, quantitative study on online dating dynamics. Given the large size of these gigantic graphs, we only investigate the metrics that might be calculated in an acceptable period of time. In what quantitative study on online dating dynamics, we introduce the metrics that are calculated on the cryptocurrencies transaction graph in this study.
Clustering coefficient shows the tendency of graph vertices to create a cluster with other vertices in the graph, and is defined as:.
Meeting online leads to happier, more enduring marriages | University of Chicago News
Massively Multiplayer Online Games (MMOGs) routinely attract millions of players but little empirical data is available to assess their players’ social experiences. In this paper, we use longitudinal data collected directly from the game to examine play and grouping patterns in one of the largest MMOGs: World of Warcraft. Our observations · The study pooled data from 43 separate studies and 11, couples who were interviewed at least twice (the interval between interviews ranged from two months to four years, depending on the study Author: Emma Betuel However, our study is the largest RT3D trans‐thoracic echocardiography study to date, and suggests that future prospective studies with technically challenging sequential valvular, annular, and MR measurements should shed light on the mechanism by which FMR repair succeeds or fails
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