ABSTRACTStating the requirements for systems or business processes as a hierarchical collection of English text that can only be analyzed/ verified by human inspection has proven time and again to be labor intensive and generally, inadequate. Projects employing a traditional document‐centered system engineering approach have experienced significant numbers of mis‐interpretations of the customer's requirements, or late‐detected design errors results in increased costs, schedule slips, reduced capability, or canceled programs. We have historically fixed requirements problems, that should have been understood and resolved early, during integration and test where it is more costly to identify and fix. Now that computerized system engineering support tools are available on the engineer's desktop, the leading edge aerospace/commercial corporations are transitioning from a document‐centered to a model‐driven system engineering approach to developing, analyzing, and managing explicit system/process specifications. Information and operational models (of varying levels of detail) not only aid in the understanding and communication of intentions such that incorrect assumptions can be eliminated early, they directly support the development of system verification plans.

If individual ballots are not pivotal and turning out is costly, why do many citizens in transitioning democracies vote? Prior approaches highlight psychological and material incentives that increase turnout. We argue that, beyond individual utility maximization, voting also reflects a person's investment in collective goods in which communities must cooperate and coordinate to mobilize members. Citizens therefore turnout, at least in part, to avoid negative social sanctions resulting from perceptions of strong community expectations and monitoring capacity. We test our predictions with original survey data from Afghanistan's 2010 parliamentary elections. We find avoidance of negative payoffs from social sanctioning drives mobilization and that sanctioning declines in areas of stronger social capital. Strength of ethnic attachments and vote-buying do not consistently increase turnout for marginal voters.

Scholars debate whether and how campaigns influence political behavior and electoral outcomes. No consistent theoretical framework, however, defines, measures, and analyzes election-related content from within the media's coverage, particularly in emerging democracies. We apply machine learning techniques on texts from nearly 100,000 news articles during South Africa's 2014 election, and use a theoretically-informed classification of election coverage to demonstrate how the conceptual scope of elections shapes voters' campaign information environment. Our results produce distinct representations of political actors and institutions during elections: a narrow classification provides heuristics cuing race, party, and incumbent performance; a broad definition reflects policy and service concerns parties debated. Topic models and word vectors show that campaign content clusters with parties and their associations with government performance and policies, but candidates vary in how much distinct coverage they obtain on valence issues. We provide methods and evidence to replicably study electoral news coverage across developing countries.

ABSTRACTMost system engineers today use graphical representations of a system to communicate its functional and data requirements. The most commonly used representations are the Function Flow Block Diagram (FFBD), Data Flow Diagram (DFD), N2 Chart, IDEF0 Diagram, and Behavior Diagram (BD). This paper discusses the characteristics of each and shows how they are related.

Using data from a UCLA survey of adults living in transition economies in Eastern Europe that was carried out in 1993, we explore the potential impact of property destruction, confiscation, and collectivization experiences on the inter-generational transmission of patience across the populations of transition economies in Eastern Europe. To do so, we make use of an index of impatience constructed from each individual’s decision to purchase expensive consumer (luxury) items. We find some evidence that offspring from families suffering property losses are more impatient than others. Second, given that the results differ across countries, a single explanation such as the intergenerational transmission of impatience is insufficient.

International development agencies invest heavily in institution building in fragile states, including expensive interventions to support democratic elections. Yet little evidence exists on whether elections enhance the domestic legitimacy of governments. Using the random assignment of an innovative election fraud-reducing intervention in Afghanistan, we find that decreasing electoral misconduct improves multiple survey measures of attitudes toward government, including: (1) whether Afghanistan is a democracy; (2) whether the police should resolve disputes; (3) whether members of parliament provide services; and (4) willingness to report insurgent behavior to security forces.

Having been declared the winner of the 2013 Kenyan presidential election, Uhuru Kenyatta pronounced the polls a ‘triumph of democracy’. But to many commentators they were anything but. Prior to the election localized violence undermined the willingness of citizens to engage in the political process in a number of areas. During the campaign, the Jubilee Alliance manipulated ICC allegations against Kenyatta and his running mate to push a divisive ‘them against us’ rhetoric that depicted their main rival, Raila Odinga, as a national traitor scheming with foreign powers to undermine Kenyan sovereignty. For their part, Odinga’s supporters emphasized the need to prevent the Kikuyu and Kalenjin – the two groups most strongly represented in the Jubilee Alliance – from securing the presidency again. As the political temperature increased, there was little space for reconciliation and nation building. Moreover, while polling day passed without incident, the electoral system fell apart as soon as the counting process began. New technology introduced as a check against rigging failed at every turn, while the Electoral Commission displayed a worrying lack of capacity. Combined with the fact that Kenyatta only narrowly cleared the 50% 1 hurdle, these failings encouraged Odinga to reject the results. But unlike in 2007, the opposition took their protest to the Courts, not the streets, and the country remained peaceful. This round table will review the main themes of the election, and consider their implications for ethnic violence, economic development, the implementation of the new constitution, and the campaign against Kenya’s culture of impunity.

This paper introduces and applies an EM algorithm for the maximum-likelihood estimation of a latent class version of the grouped-data regression model. This new model is applied to examine the effects of college athletic participation of females on incomes. No evidence for an “athlete” effect in the case of females has been found in the previous work by Long and Caudill [12], Henderson et al. [10], and Caudill and Long [5]. Our study is the first to find evidence of a lower wage for female athletes. This effect is present in a regime characterizing 42% of the sample. Further analysis indicates that female athletes in many otherwise low-paying jobs actually get paid less than non-athletes.

In a shocking victory in Ghana’s 2008 presidential election, the opposition National Democratic Congress (NDC) prevailed over the incumbent New Patriotic Party (NPP) by one-half of one percentage point, after trailing far behind the NPP according to most opinion polls. What were the attributes of voters for each party? Standard theories about elections in Africa suggest that they are little more than ethnic headcounts and that parties typically are a thin cover for ethnicity. Data from a survey we conducted shortly before the 2008 seriously challenges this view. The NDC and the NPP drew support from a range of ethnic groups and there was little evidence of ethnic block voting. Moreover, while supporters of each party do not fit a clear ethnic profile, they possess strong beliefs about the parties. In addition, in the final weeks of the election, a sizable proportion of the electorate remained undecided and was amenable to voting for either party. For these reasons we contend that the perceptions of the NDC and the NPP shaped the outcome of Ghana’s 2008 election far more than the ethnic identity of its candidates.

The goal of this paper is to introduce a partially adaptive estimator for the grouped-data regression model based on an error structure described by a mixture of two normal distributions. The model we introduce is easily estimated by maximum likelihood using the EM algorithm adapted from the work of Bartolucci and Scaccia (Comput Stat Data Anal 48:821–834, 2005). The partially adaptive estimator is applied to data used by Long and Caudill (Rev Econ Stat 73:525–531, 1991) to examine the impact of intercollegiate athletics on income. We estimate a variation of the original regression model and find that there is a considerable financial advantage for those male athletes now working in business management. This finding is consistent with the idea that athletes acquire team-building and organizational skills that are helpful in business.

This paper contributes to the growing literature examining how students' grades on in-class exams are affected by their scores on out-of-class homework assignments. Our major finding, that exam grades and homework scores are positively related, is what educators might have anticipated, yet surprisingly there is little published research that has documented a link between student learning and out-of-class exercises. Our study's results justify the suggestions of Grove and Wasserman (2006) and Hansen, Salemi, and Siegfried (2002) that principles students be given more opportunity to practice economic analysis.

AbstractThis basic tutorial identifies the elements and benefits of a complete, proven model‐based system engineering process, and demonstrates its tailorability and value for project success using vignettes from an information management system and a sample System of Systems (SoS) application. The tutorial illustrates how the model‐based system engineering process supports both document‐driven and model‐based paradigms, whether in top‐down, middle‐out, or reverse engineering environments. It discusses how to know when each element of the process has been completed, and how to develop and validate functional and physical architectures using executable architectures. The requirement for concurrent engineering, the onion model, and synchronization of models and data are presented.The participants will be introduced to a flexible system engineering process suitable for system development tasks across the complexity spectrum. In addition to the process description, the tutorial will include a sample solution to illustrate the recommended techniques, views, completion conditions, and products of an MBSE system development methodology. It will also include examples of the development of graphical views commonly used by practitioners of DoDAF and SysML approaches.This tutorial is focused on highlighting how the use of model‐based systems engineering can meet the government requirements for delivering architecture framework products while allowing the engineering organizations (industry and government) to successfully perform the systems engineering required to develop an executable design.

The use of state tax rates to provide a source of variation in the tax price of deductible goods and services may lead to biased estimates if other important state characteristics are not held constant. Omitting public welfare expenditures and religious membership is found to have little effect on the estimated price elasticity of charitable contributions. In contrast, the sensitivity of interest deductions to tax rate (price) changes is overstated when state differences in housing market characteristics are ignored.

AbstractIt comes as no surprise that incorporating an existing component into a system means you save in having to develop the component yourself—savings in schedule and development costs. What often is surprising is the impact that incorporating an existing component has on the system engineering process.This paper reviews the system engineering process and shows where the incorporation of COTS (Commercial‐off‐the‐shelf) and GOTS (Government‐off‐the‐shelf) fits into the process. It discusses the savings you get from a COTS component as well as the cost of these savings. Also described are the issues of interfaces and life cycle maintenance and modification. Once you incorporate a COTS component, how do you handle the upgrades to the COTS? Before jumping in to take advantage of COTS products, take time to consider whether the system and design process are robust enough to handle the additional constraints.

The systems engineering process as described in many books, however many minor variations may exist, is perceived by most members of INCOSE as an obvious way to pursue the development of solutions to complex problems. At the same time, most members are aware and concerned that few companies practice its precepts with total success. This paper makes the claim that sound system engineering knowledge exists but is not often well applied in practice as a premise of a study to seek out the reasons for this schism with the goal being an eventual closure of it. This paper, therefore, is an introduction to an extended activity planned by the authors.

The relationship between marginal tax rates and taxable income is analyzed with a large cross section of income tax returns filed by individuals who face different marginal tax rates because of state income tax differentials. The empirical results suggest that an increase in the marginal tax rate reduces taxable income primarily because taxpayers claim larger deductions. High-income taxpayers are found to be more responsive to tax rate changes than lower-income individuals. The findings are compared to those of other recent studies incorporating a wider range of taxpayer responses to tax rate changes than considered in this study.

Earnings differentials between state government and private industry employees are estimated for each state using 1990 Census data. Female employees in most state governments receive higher earnings than comparable private sector employees, whereas the opposite result applies to males. However, the size of the state government earnings advantage or penalty is not uniform across states for either sex. The relative earnings of state employees increase with their membership in unions and with the revenues generated by state government’s tax and financing policies .

The Tar Reform Act of 1986 combined a variety of base-broadening and base-reducing reforms with reductions in the number and levels of marginal income tar rates. An important feature of this legislation is its effect on vertical tar equity. After examining individual income tar returns filed in 1983 and 1988, this article concludes that the progressivity of the federal income tax was increased by tar reform.