Adaptive Compression of Graph Structured Text

In this paper we introduce an adaptive technique for compressing small quantities of text which are organized as a rooted directed graph. We impose a constraint on the technique such that data encountered during a traversal of any valid path through the graph must be recoverable without requiring the expansion of data that is not on the path in question. The technique we present determines the set of nodes y which are guaranteed to be encountered before reaching node x while traversing any valid path in the graph, and uses them as a basis for conditioning an LZW dictionary for the compression/expansion of the data in x. Initial results show that our improved LZW technique reduces the compressed text size by approximately 20 % more than regular LZW, and requires only minor modifications to the standard LZW decompression routine.

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Assessing the Performance of Sampling Designs for Measuring the Abundance of Understory Plants

Accurate estimation of responses of understory plants to disturbance is essential for understanding the efficacy of management activities. However, the ability to assess changes in the abundance of plants may be hampered by inappropriate sampling methodologies. Conventional methods for sampling understory plants may be precise for common species but may fail to adequately characterize abundance of less common species. We tested conventional (modified Whittaker plots and Daubenmire and point–line intercept transects) and novel (strip adaptive cluster sampling [SACS]) approaches to sampling understory plants to determine their efficacy for quantifying abundance on control and thinned-and-burned treatment units in Pinus ponderosa forests in western Montana, USA. For species grouped by growth-form and for common species, all three conventional designs were capable of estimating cover with a 50% relative margin of error with reasonable sample sizes (3–36 replicates for growth-form groups; 8–14 replicates for common species); however, increasing precision to 25% relative margin of error required sample sizes that may be infeasible (11–143 replicates for growth-form groups; 28–54 replicates for common species). All three conventional designs required enormous sample sizes to estimate cover of nonnative species as a group (29–60 replicates) and of individual less common species (62–118 replicates), even with a 50% relative margin of error. SACS was the only design that efficiently sampled less common species, requiring only 6–11% as many replicates relative to conventional designs. Conventional designs may not be effective for estimating abundance of the majority of forest understory plants, which are typically patchily distributed with low abundance, or of newly establishing nonnative plants. Novel methods such as SACS should be considered in investigations when cover of these species is of concern

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Compilation and critical review of GMPEs for the GEM-PEER Global GMPEs Project

International audienceGround-motion prediction equations (GMPEs) relate a ground-motion parameter (e.g. peak ground acceleration, PGA) to a set of explanatory variables describing the source, wave propagation path and site conditions. In the past five decades many hundreds of GMPEs for the prediction of PGA and linear elastic response spectral ordinates have been published. We discuss the pre-selection of GMPEs undertaken within the framework of the GEM-PEER Global GMPEs Project. The pre-selection criteria adopted were consistent with the current state-of-the-art in ground-motion characterization and sought to retain only the most robust GMPEs. Consideration of broad tectonic regionalization (e.g. shallow crustal seismicity in tectonically-active areas, stable continental regions and subduction zones) was made but it was assumed (based on previous studies) that strong regional differences were not present within these tectonic classes. In total about thirty GMPEs were pre-selected for closer inspection and testing to obtain a final set of ground-motion models

Transcript: Session 2: The Problem of State Judicial Campaign “Arms Races”—What Can Be Done in the State Legislatures and State Courts?

Many years ago, when my hair was still thick, this justice spoke at a conference on state court judicial elections. I was not there, but the story goes that when it came to an audience question, an idealistic young man asked this West Virginia supreme court justice: How do you go about becoming a state supreme court justice? Do you have to go to a good law school? Do you have to become involved in the state bar association? Do you have to become involved in civic organizations? Do you have to become a trial judge, then an appellate judge, and then tender your resume to the governor and hope that merit is the measure? Is that how you have to do it? Without pausing for an ethical second, the bold justice from West Virginia said, “Money, my man, money.” This is the realist backdrop or subtext for much of the discussion about Caperton and also White. At least some of the subtext includes an animosity to judicial elections and an attempt to defang them

Transcript: Session 2: The Problem of State Judicial Campaign “Arms Races”—What Can Be Done in the State Legislatures and State Courts?

Many years ago, when my hair was still thick, this justice spoke at a conference on state court judicial elections. I was not there, but the story goes that when it came to an audience question, an idealistic young man asked this West Virginia supreme court justice: How do you go about becoming a state supreme court justice? Do you have to go to a good law school? Do you have to become involved in the state bar association? Do you have to become involved in civic organizations? Do you have to become a trial judge, then an appellate judge, and then tender your resume to the governor and hope that merit is the measure? Is that how you have to do it? Without pausing for an ethical second, the bold justice from West Virginia said, “Money, my man, money.” This is the realist backdrop or subtext for much of the discussion about Caperton and also White. At least some of the subtext includes an animosity to judicial elections and an attempt to defang them