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295,414 result(s) for "Proxies"
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Behind the Scenes: The Corporate Governance Preferences of Institutional Investors
We survey institutional investors to better understand their role in the corporate governance of firms. Consistent with a number of theories, we document widespread behind-the-scenes intervention as well as governance-motivated exit. These governance mechanisms are viewed as complementary devices, with intervention typically occurring prior to a potential exit. We further find that long-term investors and investors that are less concerned about stock liquidity intervene more intensively. Finally, we find that most investors use proxy advisors and believe that the information provided by such advisors improves their own voting decisions.
Proxy design: a method for involving proxy users to speak on behalf of vulnerable or unreachable users in co-design
PurposeDesigning digital artifacts is not a linear, straightforward process. This is particularly true when applying a user-centered design approach, or co-design, with users who are unable to participate in the design process. Although the reduced participation of a particular user group may harm the end result, the literature on solving this issue is sparse. In this article, proxy design is outlined as a method for involving a user group as proxy users to speak on behalf of a group that is difficult to reach. The article investigates the following research question: How can roleplaying be embedded in co-design to engage users as proxies on behalf of those who are unable to represent themselves?Design/methodology/approachThe article presents a design ethnography spanning three years at a cancer rehabilitation clinic, where digital artifacts were designed to be used collaboratively by nurses and patients. The empirical data were analyzed using content analysis and consisted of 20 observation days at the clinic, six proxy design workshops, 21 telephone consultations between patients and nurses, and log data from the digital artifact.FindingsThe article shows that simulated consultations, with nurses roleplaying as proxies for patients ignited and initiated the design process and enabled an efficient in-depth understanding of patients. Moreover, the article reveals how proxy design as a method further expanded the design. The study findings illustrate: (1) proxy design as a method for initiating design, (2) proxy design as an embedded element in co-design and (3) six design guidelines that should be considered when engaging in proxy design.Originality/valueThe main contribution is the conceptualization of proxy design as a method that can ignite and initiate the co-design process when important users are unreachable, vulnerable or unable to represent themselves in the co-design process. More specifically, based on the empirical findings from a design ethnography that involved nurses as proxy users speaking on behalf of patients, the article shows that roleplaying in proxy design is a fitting way of initiating the design process, outlining proxy design as an embedded element of co-design.
Assessing 5 years of GOSAT Proxy XCH.sub.4 data and associated uncertainties
We present 5 years of GOSAT XCH.sub.4 retrieved using the \"proxy\" approach. The Proxy XCH.sub.4 data are validated against ground-based TCCON observations and are found to be of high quality with a small bias of 4.8 ppb (∼ 0.27 %) and a single-sounding precision of 13.4 ppb (∼ 0.74 %). The station-to-station bias (ameasure of the relative accuracy) is found to be 4.2 ppb. For the first time the XCH.sub.4 / XCO.sub.2 ratio component of the Proxy retrieval is validated (bias of 0.014 ppb ppm.sup.−1 (∼ 0.30 %), single-sounding precision of 0.033 ppb ppm.sup.−1 (∼ 0.72 %)). The uncertainty relating to the model XCO.sub.2 component of the Proxy XCH.sub.4 is assessed through the use of an ensemble of XCO.sub.2 models. While each individual XCO.sub.2 model is found to agree well with the TCCON validation data (r = 0.94-0.97), it is not possible to select one model as the best from our comparisons. The median XCO.sub.2 value of the ensemble has a smaller scatter against TCCON (a standard deviation of 0.92 ppm) than any of the individual models whilst maintaining a small bias (0.15 ppm). This model median XCO.sub.2 is used to calculate the Proxy XCH.sub.4 with the maximum deviation of the ensemble from the median used as an estimate of the uncertainty. We compare this uncertainty to the a posteriori retrieval error (which is assumed to reduce with sqrt(N)) and find typically that the model XCO.sub.2 uncertainty becomes significant during summer months when the a posteriori error is at its lowest due to the increase in signal related to increased summertime reflected sunlight. We assess the significance of these model and retrieval uncertainties on flux inversion by comparing the GOSAT XCH.sub.4 against modelled XCH.sub.4 from TM5-4DVAR constrained by NOAA surface observations (MACC reanalysis scenario S1-NOAA). We find that for the majority of regions the differences are much larger than the estimated uncertainties. Our findings show that useful information will be provided to the inversions for the majority of regions in addition to that already provided by the assimilated surface measurements.
Developing Proxies in Secondary Carbonates with Application to Enso Variability and Basin-Wide Paleo-Hydrology
This thesis develops new, and expands existing, methods of reconstructing paleoclimate from geochemical proxies hosted in secondary carbonate precipitates. This is done by: i) Developing a new multi-proxy approach for using lacustrine cave carbonates (LCCs) to reconstruct past shifts in precipitation-evaporation (P-E) over lake drainage basins, and ii) Investigating the suitability of speleothems as paleo-ENSO archives. Chapters 2 and 3 use modelled and measured values from LCC samples to generate a framework for understanding how Mg/Ca, U/Ca and δ44/42Ca in LCCs can be used as a combined multi-proxy approach to reconstruct past shifts in P-E. This multi-proxy approach is subsequently used to generate a novel reconstruction of P-E over the Bonneville Basin (a terminal basin in the Great Basin region of the southwestern United States), during Heinrich Stadial 1. Results suggest that moisture supply to the Great Basin region was impacted by a southwards shift of the ITCZ and variations in the elevation of North American ice sheets during Heinrich Stadial 1. Chapter 4 investigates the suitability of applying speleothem BA03 as a paleo-ENSO archive. Firstly, the impacts of age model and δ18O uncertainties on speleothem ENSO variability reconstructions are quantified. A total of eight high resolution (> 2 samples per year) δ18O time-series are then used to reconstruct shifts in ENSO variability over the Holocene. This new ENSO variability reconstruction suggests a reduction in ENSO variability during the mid-Holocene (5.68 kyr BP - 3.78 kyr BP), the termination of which coincides with the end of the so called \"4.2 Kyr Event\". This thesis advances the paleoclimate application of numerous geochemical proxies, expanding the use of precisely dated, high-resolution secondary carbonate archives.
A Reconstruction of Regional and Global Temperature for the Past 11,300 Years
Surface temperature reconstructions of the past 1500 years suggest that recent warming is unprecedented in that time. Here we provide a broader perspective by reconstructing regional and global temperature anomalies for the past 11,300 years from 73 globally distributed records. Early Holocene (10,000 to 5000 years ago) warmth is followed by ∼0.7°C cooling through the middle to late Holocene (<5000 years ago), culminating in the coolest temperatures of the Holocene during the Little Ice Age, about 200 years ago. This cooling is largely associated with ∼2°C change in the North Atlantic. Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ∼75% of the Holocene temperature history. Intergovernmental Panel on Climate Change model projections for 2100 exceed the full distribution of Holocene temperature under all plausible greenhouse gas emission scenarios.
The use of proxies and proxy-reported measures
Aims Proxy reports are often used when patients are unable to self-report. It is unclear how proxy measures are currently in use in adult health care and research settings. We aimed to describe how proxy reports are used in these settings, including the use of measures developed specifically for proxy reporting in adult health populations. Methods We systematically searched Medline, PsycINFO, PsycTESTS, CINAHL and EMBASE from database inception to February 2018. Search terms included a combination of terms for quality of life and health outcomes, proxy-reporters, and health condition terms. The data extracted included clinical context, the name of the proxy measure(s) used and other descriptive data. We determined whether the measures were developed specifically for proxy use or were existing measures adapted for proxy use. Results The database search identified 17,677 possible articles, from which 14,098 abstracts were reviewed. Of these, 11,763 were excluded and 2335 articles were reviewed in full, with 880 included for data extraction. The most common clinical settings were dementia (30%), geriatrics (15%) and cancer (13%). A majority of articles (51%) were paired studies with proxy and patient responses for the same person on the same measure. Most paired studies (77%) were concordance studies comparing patient and proxy responses on these measures. Discussion Most published research using proxies has focused on proxy-patient concordance. Relatively few measures used in research with proxies were specifically developed for proxy use. Future work is needed to examine the performance of measures specifically developed for proxies. Systematic review registration PROSPERO No. CRD42018103179
Abrupt Shifts in Horn of Africa Hydroclimate Since the Last Glacial Maximum
The timing and abruptness of the initiation and termination of the Early Holocene African Humid Period are subjects of ongoing debate, with direct consequences for our understanding of abrupt climate change, paleoenvironments, and early human cultural development. Here, we provide proxy evidence from the Horn of Africa region that documents abrupt transitions into and out of the African Humid Period in northeast Africa. Similar and generally synchronous abrupt transitions at other East African sites suggest that rapid shifts in hydroclimate are a regionally coherent feature. Our analysis suggests that the termination of the African Humid Period in the Horn of Africa occurred within centuries, underscoring the nonlinearity of the region's hydroclimate.
Tree-Ring-Reconstructed Summer Temperatures from Northwestern North America during the Last Nine Centuries
Northwestern North America has one of the highest rates of recent temperature increase in the world, but the putative “divergence problem” in dendroclimatology potentially limits the ability of tree-ring proxy data at high latitudes to provide long-term context for current anthropogenic change. Here, summer temperatures are reconstructed from aPicea glaucamaximum latewood density (MXD) chronology that shows a stable relationship to regional temperatures and spans most of the last millennium at the Firth River in northeastern Alaska. The warmest epoch in the last nine centuries is estimated to have occurred during the late twentieth century, with average temperatures over the last 30 yr of the reconstruction developed for this study [1973–2002 in the Common Era (CE)] approximately 1.3° ± 0.4°C warmer than the long-term preindustrial mean (1100–1850 CE), a change associated with rapid increases in greenhouse gases. Prior to the late twentieth century, multidecadal temperature fluctuations covary broadly with changes in natural radiative forcing. The findings presented here emphasize that tree-ring proxies can provide reliable indicators of temperature variability even in a rapidly warming climate.
Assimilation of Time-Averaged Pseudoproxies for Climate Reconstruction
The efficacy of a novel ensemble data assimilation (DA) technique is examined in the climate field reconstruction (CFR) of surface temperature. A minimalistic, computationally inexpensive DA technique is employed that requires only a static ensemble of climatologically plausible states. Pseudoproxy experiments are performed with both general circulation model (GCM) and Twentieth Century Reanalysis (20CR) data by reconstructing surface temperature fields from a sparse network of noisy pseudoproxies. The DA approach is compared to a conventional CFR approach based on principal component analysis (PCA) for experiments on global domains. DA outperforms PCA in reconstructing global-mean temperature in all experiments and is more consistent across experiments, with a range of time series correlations of 0.69–0.94 compared to 0.19–0.87 for the PCA method. DA improvements are even more evident in spatial reconstruction skill, especially in sparsely sampled pseudoproxy regions and for 20CR experiments. It is hypothesized that DA improves spatial reconstructions because it relies on coherent, spatially local temperature patterns, which remain robust even when glacial states are used to reconstruct nonglacial states and vice versa. These local relationships, as utilized by DA, appear to be more robust than the orthogonal patterns of variability utilized by PCA. Comparing results for GCM and 20CR data indicates that pseudoproxy experiments that rely solely on GCM data may give a false impression of reconstruction skill.
Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly
Global temperatures are known to have varied over the past 1500 years, but the spatial patterns have remained poorly defined. We used a global climate proxy network to reconstruct surface temperature patterns over this interval. The Medieval period is found to display warmth that matches or exceeds that of the past decade in some regions, but which falls well below recent levels globally. This period is marked by a tendency for La Niña-like conditions in the tropical Pacific. The coldest temperatures of the Little Ice Age are observed over the interval 1400 to 1700 C.E., with greatest cooling over the extratropical Northern Hemisphere continents. The patterns of temperature change imply dynamical responses of climate to natural radiative forcing changes involving El Niño and the North Atlantic Oscillation-Arctic Oscillation.