Showing papers on "Proxy (statistics) published in 2015"

Night-time light data: A good proxy measure for economic activity?

Abstract: Much research has suggested that night-time light (NTL) can be used as a proxy for a number of variables, including urbanization, density, and economic growth. As governments around the world either collect census data infrequently or are scaling back the amount of detail collected, alternate sources of population and economic information like NTL are being considered. But, just how close is the statistical relationship between NTL and economic activity at a fine-grained geographical level? This paper uses a combination of correlation analysis and geographically weighted regressions in order to examine if light can function as a proxy for economic activities at a finer level. We use a fine-grained geo-coded residential and industrial full sample micro-data set for Sweden, and match it with both radiance and saturated light emissions. We find that the correlation between NTL and economic activity is strong enough to make it a relatively good proxy for population and establishment density, but the correlation is weaker in relation to wages. In general, we find a stronger relation between light and density values, than with light and total values. We also find a closer connection between radiance light and economic activity, than with saturated light. Further, we find the link between light and economic activity, especially estimated by wages, to be slightly overestimated in large urban areas and underestimated in rural areas.

Device management proxy for secure devices

Abstract: A hardware device architecture is described that improves security and flexibility in access to hardware device settings. A device management proxy service is digitally signed and granted access to device settings. Applications are then digitally provisioned by the proxy service and only validated signed requests from applications are permitted to change hardware device settings. Further granularity over hardware device settings is achieved through user accounts and groups established by the applications.

The Impact of Uncertainty Shocks under Measurement Error: A Proxy SVAR Approach

Abstract: A growing literature considers the impact of uncertainty using SVAR models that include proxies for uncertainty shocks as endogenous variables. In this paper, we consider the impact of measurement error in these proxies on the estimated impulse responses. We show via a Monte Carlo experiment that measurement error can result in attenuation bias in impulse responses. In contrast, the proxy SVAR that uses the uncertainty shock proxy as an instrument does not suffer from this bias. Applying this latter method to the Bloom (2009) data set results in impulse responses to uncertainty shocks that are larger in magnitude and more persistent than those obtained from a recursive SVAR.

A sharper image? Estimates of the precision of nighttime lights as a proxy for economic statistics

Abstract: Much aggregate social-science analysis relies upon the standard national income and product accounts as a source of economic data. These are recognized to be defective in many poor countries, and are missing at the regional level for large parts of the world. Using updated luminosity (or nighttime lights) data, the present study examines whether such data contain useful information for estimating national and regional incomes and output. The bootstrap method is used for estimating the statistical precision of the estimates of the contribution of the lights proxy. We conclude that there may be substantial cross-sectional information in lights data for countries with low-quality statistical systems. However, lights data provide very little additional information for countries with high-quality data wherever standard data are available. The largest statistical concerns arise from uncertainties about the precision of standard national accounts data.

Outsourcing Shareholder Voting to Proxy Advisory Firms

Abstract: This paper examines the economic consequences of institutional investors outsourcing research and voting decisions in public company elections to proxy advisory firms. We investigate the implications of these decisions in the context of shareholder say-on-pay voting required in 2011 under the Dodd-Frank Act. We find three primary results: proxy advisory firm recommendations have a substantive impact on say-on-pay voting outcomes, a substantial number of firms change their compensation programs in the time period before formal shareholder votes in a manner consistent with the features known to be favored by proxy advisory firms in an effort to avoid negative voting recommendations, and the stock market reaction to these compensation program changes is statistically negative. These results suggest that outsourcing voting to proxy advisory firms appears to have the unintended economic consequence that boards of directors are induced to make choices that decrease shareholder value.

Direct voting and proxy voting

Abstract: I develop a hybrid of direct democracy and representative democracy in which each citizen may vote directly on each issue, or delegate his vote on any issue to a representative (that is, a proxy) of his own choosing. I construct both an axiomatic argument for such a system and an argument based on its ability to ameliorate the information problems inherent in both direct and representative democracy. I also propose practical measures for implementation, including new variations on existing proxy system proposals. These new variations include a ‘Dodgsonesque’ procedure, a proportional agenda-setting procedure, a provision for virtual committees, and a provision for continual consideration of issues.

Endpoint management system providing an application programming interface proxy service

Abstract: An endpoint management and proxy system is described, by which users can manage and enable exposure of application programming interfaces ("APIs") usable to cause execution of program code on a remote or third party system. Systems and methods are disclosed which facilitate the handling of user requests to perform certain tasks on remote systems. The endpoint management system allows the application developer to define and specify a first proxy API which maps to a second API associated with the remote system. The endpoint proxy system receives requests to execute the proxy API, determines the API mapping, and sends one or more backend API requests to execute program codes by the associated remote systems. Responses from the remote systems are received by the endpoint proxy system which parses and/or transforms the results associated with the response and generates an output result for response back to the user computing systems.

Dieting: proxy or cause of future weight gain?

Abstract: The relationship between dieting and body mass has a long and controversial history. This paper aims to help resolve this issue by making two key distinctions. The first is between dieting as a cause of weight gain/regain and as a proxy risk factor for identifying non-obese individuals prone to weight gain for reasons other than dieting. The second is between the body mass that is attained following one or more weight loss/regain cycles and the body mass that might have been reached had dieting never been undertaken. Evidence is reviewed on the relation between recent diet-induced weight loss and sustained weight loss (weight suppression), on the one hand, and weight regain, on the other hand. Furthermore, the reason that a history of dieting in non-obese individuals reflects a susceptibility to future weight gain is explained. It is concluded that (i) diet-induced weight loss hastens weight regain but a history of weight loss diets does not cause weight gain beyond that which would occur in the absence of dieting, and (ii) weight loss dieting in non-obese individuals does not cause future weight gain but is simply a proxy risk factor reflecting a personal vulnerability to weight gain and living in an obesogenic environment.

Managerial Activeness and Mutual Fund Performance

Abstract: A closet indexer is more likely to meet a value-weighted investment benchmark by value weighting the portfolio. Following this intuition, we introduce a simple measure of active management, the absolute difference between the value weights and actual weights held by a fund, summed across its holdings. This proxy captures managerial skill: active funds outperform passive ones by 2.5% annually. Compared with known measures of skill, our proxy robustly predicts fund flows, asset growth, factor-adjusted performance, and value added. Its predictive ability is orthogonal to that of other measures and is robust to controlling for volatility timing, past performance, and style. (JEL G10, G12, G14, G20, G23)

Differences in proxy-reported and patient-reported outcomes: assessing health and functional status among medicare beneficiaries

Abstract: Proxy responses are very common when surveys are conducted among the elderly or disabled population. Outcomes reported by proxy may be systematically different from those obtained from patients directly. The objective of the study is to examine the presence, direction, and magnitude of possible differences between proxy-reported and patient-reported outcomes in health and functional status measures among Medicare beneficiaries. This study is a pooled cross-sectional study of a nationally representative sample of community-dwelling Medicare beneficiaries from 2006 to 2011. Survey respondents can respond to the Medicare Current Beneficiary Survey either by themselves or via proxies. Health and functional status was assessed across five domains: physical, affective, cognitive, social, and sensory status. Propensity score matching was used to get matched pairs of patient-reports and proxy-reports. After applying the propensity score matching, the study identified 7,780 person-years of patient-reports paired with 7,780 person-years of proxy-reports. Except for the sensory limitation, differences between proxy-reported and patient-reported outcomes were present in physical, affective, cognitive, and social limitations. Compared to patient-reports, a question regarding survey respondents’ difficulties in managing money was associated with the largest proxy response bias (relative risk, RR = 3.83). With few exceptions, the presence, direction, and magnitude of differences between proxy-reported and patient-reported outcomes did not vary much in the subgroup analysis. When there is a difference between proxy-reported and patient-reported outcomes, proxies tended to report more health and functional limitations among the elderly and disabled population. The extent of proxy response bias depended on the domain being tested and the nature of the question being asked. Researchers should accept proxy reports for sensory status and objective, observable, or easy questions. For physical, affective, cognitive, or social status and private, unobservable, or complex questions, proxy-reported outcomes should be used with caution when patient-reported outcomes are not available.

The Performance of School Assignment Mechanisms in Practice

Abstract: Theory points to a potential trade-off between two main school assignment mechanisms; Boston and Deferred Acceptance (DA). While DA is strategy-proof and gives a stable matching, Boston might outperform DA in terms of ex-ante efficiency. We quantify the (dis)advantages of the mechanisms by using information about actual choices under Boston complemented with survey data eliciting students' school preferences. We find that under Boston around 8% of the students apply to another school than their most-preferred school. We compare allocations resulting from Boston with DA with single tie-breaking (one central lottery; DA-STB) and multiple tie-breaking (separate lottery per school; DA-MTB). DA-STB places more students in their top-n schools, for any n, than Boston and results in higher average welfare. We find a trade-off between DA-STB and DA-MTB. DA-STB places more students in their single most-preferred school than DA-MTB, but fewer in their top-n, for n >= 2. Finally, students from disadvantaged backgrounds benefit most from a switch from Boston to any of the DA mechanisms.

The Disciplinary Effects of Proxy Contests

Abstract: Using a manually collected data set of all proxy contests from 1994 through 2012, I show that proxy contests play an important role in hostile corporate governance. Target shareholders benefit from proxy contests: the average abnormal returns reach 6.5% around proxy contest announcements. Proxy contests that address firms' business strategies and undervaluation are most beneficial for shareholders. In contrast, proxy contests that aim at changing capital structure and governance do not lead to higher firm values. Relative to matching firms, future targets are smaller, they have higher stock liquidity, higher institutional and activist ownership, lower leverage and market valuation, and higher investments. While most of these characteristics predict proxy contests in time-series, prior to proxy contests targets also experience poor stock performance, decreases in investments, increases in cash reserves and payouts to shareholders, and increases in management's entrenchment. These changes in corporate policies are consistent with targets' attempts to affect the probability of a proxy contest.

The impact of bank size on profitability“an empirical study on listed jordanian commercial banks”

Abstract: This study is aimed to investigate the effect of bank size on its profitability for Jordanian listed commercial banks within different size bank categories. Data for Jordanian commercial banks for the years from 2007 up to 2012 were used to classify banks for three categories according to their asset size, in respect to their Total Assets. Profitability was measured by Return on Equity (ROE) as dependent variables. The study is constructed to reveal if there is a statistical difference in profitability according to size. Simple regression was applied by using dummy variables for categories to proxy asset size. The results of the study revealed a significance difference in the profitability of these different sized banks.

Economic development and market potential: European regional income differentials, 1870-1913

Abstract: This dissertation examines the extent to which proximity to markets - as measured by market potential, the trade cost-weighted sum of surrounding regions’ GDP - can explain late-nineteenth century Europe’s regional per capita income differentials. The research questions are: (1) was the spatial distribution of regional income random; (2) how helpful are traditional explanations - coal and institutions - of regional income; (3) how helpful is market potential when controlling for traditional explanations; and (4) did market potential have an effect on other determinants of income? This dissertation finds that: (1) the distribution of regional per capita income increasingly concentrated in the northwest; that there was little tendency to income convergence; and regional inequalities were higher within than between countries; (2) while a measure of regional institutions is correlated with income, simple distance-to-coal and a cost-to-coal measures are not; (3) market potential has a significant effect on income; foreign market potential more so than domestic; and increasing core relative to peripheral market potential results in perpherial income losses; and (4) changes in literacy rates, a proxy for human capital, responded to changes in market potential. In conclusion, a new economic geography framework with market potential at its core fits the historical experience well. Certain regions performed better than others generally because they had cheaper access to markets. At the start of the period, trade costs were high, and so economic activity - long concentrated in Britain - was spread out more or less evenly across the Continent. By the end of the period, when trade costs dropped dramatically, economic activity concentrated in the northwest of Europe at the cost of the periphery.

Services within reverse proxy servers

Abstract: Embodiments of the invention provide techniques for processing messages transmitted between computer networks. Messages, such as requests from client devices for web services and other web content may be transmitted between multiple computer networks. Intermediary devices or applications such as proxy servers may receive, process, and transmit the messages between the communication endpoints. In some embodiments, a reverse proxy server may be configured to dynamically generate Representational State Transfer (REST) services and REST resources within the reverse proxy server. The REST services and REST resources within the reverse proxy server may handle incoming requests from client devices and invoke backend web services, thereby allowing design abstraction and/or enforcement of various security policies on the reverse proxy server.

Influence of Public Opinion on Investor Voting and Proxy Advisors

Abstract: Institutional investors vote corporate proxies on behalf of underlying investors and beneficiaries. We show a strong relation between this voting and public opinion on corporate governance (as reflected in media coverage and surveys), with similarly strong results for voting by mutual funds. We also find that proxy advisors’ recommendations are associated with public opinion. Our results suggest that institutional investors and proxy advisors pay attention to the changing opinions of their beneficiaries and shareholders, as reflected in their voting decisions, and that the proxy voting process serves as a channel for the public to influence corporate behavior.

Identifying Structural Vars with a Proxy Variable and a Test for a Weak Proxy

Abstract: This paper develops a simple estimator to identify structural shocks in vector autoregressions (VARs) by using a proxy variable that is correlated with the structural shock of interest but uncorrelated with other structural shocks. When the proxy variable is weak, modeled as local to zero, the estimator is inconsistent and converges to a distribution. This limiting distribution is characterized, and the estimator is shown to be asymptotically biased when the proxy variable is weak. The F statistic from the projection of the proxy variable onto the VAR errors can be used to test for a weak proxy variable, and the critical values for different VAR dimensions, levels of asymptotic bias, and levels of statistical significance are provided. An important feature of this F statistic is that its asymptotic distribution does not depend on parameters that need to be estimated.

Effects of categorization method, regression type, and variable distribution on the inflation of Type‐I error rate when categorizing a confounding variable

Abstract: The loss of signal associated with categorizing a continuous variable is well known, and previous studies have demonstrated that this can lead to an inflation of Type-I error when the categorized variable is a confounder in a regression analysis estimating the effect of an exposure on an outcome. However, it is not known how the Type-I error may vary under different circumstances, including logistic versus linear regression, different distributions of the confounder, and different categorization methods. Here, we analytically quantified the effect of categorization and then performed a series of 9600 Monte Carlo simulations to estimate the Type-I error inflation associated with categorization of a confounder under different regression scenarios. We show that Type-I error is unacceptably high (>10% in most scenarios and often 100%). The only exception was when the variable categorized was a continuous mixture proxy for a genuinely dichotomous latent variable, where both the continuous proxy and the categorized variable are error-ridden proxies for the dichotomous latent variable. As expected, error inflation was also higher with larger sample size, fewer categories, and stronger associations between the confounder and the exposure or outcome. We provide online tools that can help researchers estimate the potential error inflation and understand how serious a problem this is. Copyright © 2014 John Wiley & Sons, Ltd.

Institutions and Growth: A GMM/IV Panel VAR Approach

Abstract: Both sides of the institutions and growth debate have resorted largely to microeconometric techniques in testing hypotheses. In this paper, I build a panel structural vector autoregression (SVAR) model for a short panel of 119 countries over 10 years and find support for the institutions hypothesis. Controlling for individual fixed effects, I find that exogenous shocks to a proxy for institutional quality have a positive and statistically significant effect on GDP per capita. On average, a 1 percent shock in institutional quality leads to a peak 1.7 percent increase in GDP per capita after six years. Results are robust to using a different proxy for institutional quality. There are different dynamics for advanced economies and developing countries. This suggests diminishing returns to institutional quality improvements.

Data query method and system and storage medium

Abstract: The present disclosure discloses a data query system, method, and storage medium. The data query system includes a proxy server and at least one proxy client. The proxy server is disposed on a server that serves as a data provider, and is configured to provide the proxy client with a data delivery service. The proxy client is disposed on a client that serves as a data user, and is configured to obtain data from the proxy server and save the data and provide a data query service. The proxy client thus includes a data obtaining module, a data query module, and a second shared memory. Accordingly, the present disclosure further discloses a data query method. The present disclosure has a simple structure, achieves fast data update, requires a low deployment cost, saves bandwidth resources, and achieves excellent service performance.

Web-Based Assessment of Outcomes After Subarachnoid and Intracerebral Hemorrhage: A New Patient Centered Option for Outcomes Assessment

Abstract: Clinical outcomes are typically assessed by trained staff. We tested the hypothesis that outcomes reported by the patient or a caregiver on the web would be correlated with a validated interview. We assessed surviving patients with intracerebral and subarachnoid hemorrhage at 1- , 3- , and 12-month follow-up with a validated interview for the modified Rankin Scale (mRS, a validated ordinal scale from 0, no symptoms to 5, severe disability). Health-related quality of life (HRQoL) was assessed on the web with NIH Patient-Reported Outcomes Measurement Information System (PROMIS) and Neuro-QOL using computer adaptive testing by the patient, proxy reporting by a caregiver, or proxy entry by study staff. A coincident mRS and HRQoL assessment was available for 149 (71 %) of 209 patients at one, three, or 12 months. There were 89 assessments with proxy entry by study staff, 89 by the patient on the web, and 58 with proxy report by a caregiver on the web. PROMIS physical function assessments were completed in median of 4 questions, and T scores were associated with the mRS (P < 0.001), regardless of respondent. Mean T scores in every category of the mRS were different from every other category (P ≤ 0.003 for all). Results were similar for Neuro-QOL mobility. Web-based HRQoL assessment with NIH PROMIS and Neuro-QOL is feasible and correlated with a validated interview for the mRS. T scores distinguished between individual categories of the mRS, detecting modest differences in physical function and mobility HRQoL that are difficult to detect with the mRS. PROMIS and Neuro-QOL provide powerful and sensitive outcomes for potentially large cohorts.

A Proxy Identifier Based on Patterns in Traffic Flows

Abstract: Proxies are used commonly on today's Internet. On one hand, end users can choose to use proxies for hiding their identities for privacy reasons. On the other hand, ubiquitous systems can use it for intercepting the traffic for purposes such as caching. In addition, attackers can use such technologies to anonymize their malicious behaviours and hide their identities. Identification of such behaviours is important for defense applications since it can facilitate the assessment of security threats. The objective of this paper is to identify proxy traffic as seen in a traffic log file without any access to the proxy server or the clients behind it. To achieve this: (i) we employ a mixture of log files to represent real-life proxy behavior, and (ii) we design and develop a data driven machine learning based approach to provide recommendations for the automatic identification of such behaviours. Our results show that we are able to achieve our objective with a promising performance even though the problem is very challenging.

Re-Encryption Verifiability: How to Detect Malicious Activities of a Proxy in Proxy Re-Encryption

Abstract: In this paper, we introduce a new functionality for proxy re-encryption (PRE) that we call re-encryption verifiability. In a PRE scheme with re-encryption verifiability (which we simply call verifiable PRE, or VPRE), a receiver of a re-encrypted ciphertext can verify whether the received ciphertext is correctly transformed from an original ciphertext by a proxy, and thus can detect illegal activities of the proxy. We formalize the security model for a VPRE scheme, and show that the single-hop uni-directional PRE scheme by Hanaoka et al. (CT-RSA 2012) can be extended to a secure VPRE scheme.

Do the Rich Save More? Evidence from Canada

Abstract: This paper provides new evidence on the long-standing question of whether more affluent households save a larger fraction of their income. The major difficulty in empirically assessing the relationship between incomes and saving rates is to construct a credible proxy for long-run income—purged of transitory fluctuations and measurement error. The Canadian Family Expenditure Survey provides us with both unusually good data on savings rates and potential predictors with which we can construct reliable long-run income proxies. Our empirical analysis suggests that the estimated relationship between saving rates and long-run incomes is sensitive to the predictor used to proxy long-run income. Nevertheless, our preferred estimates indicate that, except for poorest households (who simply do not save), saving rates do not differ substantially across predicted long-run income groups.