“Why Didn’t You Just Ask?” Underestimating the Discomfort of Help-Seeking

Across four studies we demonstrate that people in a position to provide help tend to underestimate the role that embarrassment plays in decisions about whether or not to ask for help. As a result, potential helpers may overestimate the likelihood that people will ask for help (Studies 1 and 2). Further, helpers may be less inclined to allocate resources to underutilized support programs than help-seekers because they are less likely to attribute low levels of use to help-seekers’ concerns with embarrassment (Study 3). Finally, helpers may misjudge the most effective means of encouraging help-seeking behavior - emphasizing the practical benefits of asking for help, rather than attempting to assuage help-seekers’ feelings of discomfort (Study 4)

Are all fast radio bursts repeating sources?

We present Monte-Carlo simulations of a cosmological population of repeating fast radio burst (FRB) sources whose comoving density follows the cosmic star formation rate history. We assume a power-law model for the intrinsic energy distribution for each repeating FRB source located at a randomly chosen position in the sky and simulate their dispersion measures (DMs) and propagation effects along the chosen lines-of-sight to various telescopes. In one scenario, an exponential distribution for the intrinsic wait times between pulses is chosen, and in a second scenario we model the observed pulse arrival times to follow a Weibull distribution. For both models we determine whether the FRB source would be deemed a repeater based on the telescope sensitivity and time spent on follow-up observations. We are unable to rule out the existence of a single FRB population based on comparisons of our simulations with the longest FRB follow-up observations performed. We however rule out the possibility of FRBs 171020 and 010724 repeating with the same rate statistics as FRB 121102 and also constrain the slope of a power-law fit to the FRB energy distribution to be $-2.0 < \gamma <-1.0$. All-sky simulations of repeating FRB sources imply that the detection of singular events correspond to the bright tail-end of the adopted energy distribution due to the combination of the increase in volume probed with distance, and the position of the burst in the telescope beam.Comment: 10 pages, 4 figures, accepted for publication in MNRA

Galactic Archaeology and Minimum Spanning Trees

Chemical tagging of stellar debris from disrupted open clusters and associations underpins the science cases for next-generation multi-object spectroscopic surveys. As part of the Galactic Archaeology project TraCD (Tracking Cluster Debris), a preliminary attempt at reconstructing the birth clouds of now phase-mixed thin disk debris is undertaken using a parametric minimum spanning tree (MST) approach. Empirically-motivated chemical abundance pattern uncertainties (for a 10-dimensional chemistry-space) are applied to NBODY6-realised stellar associations dissolved into a background sea of field stars, all evolving in a Milky Way potential. We demonstrate that significant population reconstruction degeneracies appear when the abundance uncertainties approach 0.1 dex and the parameterised MST approach is employed; more sophisticated methodologies will be required to ameliorate these degeneracies.Comment: To appear in "Multi-Object Spectroscopy in the Next Decade: Big Questions, Large Surveys and Wide Fields"; Held: Santa Cruz de La Palma, Canary Islands, Spain, 2-6 Mar 2015; ed. I Skillen & S. Trager; ASP Conference Series (Figures now optimised for B&W printing

Table II: Baseline Values of Primary and Secondary Outcomes for Placebo and Botox Groups

Table of supplemental data to accompany an article submitted for publication by the author

Document Classification in Support of Automated Metadata Extraction Form Heterogeneous Collections

A number of federal agencies, universities, laboratories, and companies are placing their documents online and making them searchable via metadata fields such as author, title, and publishing organization. To enable this, every document in the collection must be catalogued using the metadata fields. Though time consuming, the task of identifying metadata fields by inspecting the document is easy for a human. The visual cues in the formatting of the document along with accumulated knowledge and intelligence make it easy for a human to identify various metadata fields. Even with the best possible automated procedures, numerous sources of error exist, including some that cannot be controlled, such as scanned documents with text obscured by smudges, signatures, or stamps. A commercially viable process for metadata extraction must remain robust in the presence of these external sources of error as well as in the face of the uncertainty that accompanies any attempts to automate intelligent behavior. While extraction accuracy and completeness must be the primary goal of an extraction system, the ability to detect and report questionable results is equally important for a production quality system, since it promotes confidence in the system. We have developed and demonstrated a novel system for extracting metadata. First, a document is examined in an attempt to recognize it as an instance of a known document layout. Then a template, a scripted description of how to associate blocks of text in the layout with metadata fields, is applied to the document to extract the metadata. The extraction is validated after post-processing to evaluate the quality of the extraction and, if necessary, to flag untrusted extractions for human recognition. The success or failure of the template approach is directly tied to document classification, which is the ability to match the document to the proper template correctly and consistently. Document classification in our system is implemented as a module which applies every template available in the system to a document to find candidate templates that extract any data at all. The candidate templates are evaluated by a validation module to select the best performing template. This method is called post hoc classification. Post hoc classification is not only effective at selecting the correct class but it also excels at minimizing false positives. It is, however, very sensitive to changes in the template collection and to poorly written templates. While this dissertation examines the evolution and all the major components of an automated metadata extraction system, the primary focus is on the problem of document classification. The main thrust of my research has been investigating alternative methods of document classification to replace or supplement post hoc classification. I experimented with machine learning techniques as an additional input factor for the post hoc classification script or the final validation script

A Creative Writing Honors Thesis: Guardians of Alyataus

This is a creative writing thesis. It is a novel of roughly 55,000 words that is intended for the reading audience of ages 12-16. It is in the genre of medieval/fantasy/adventure. This literary work takes its inspiration from many young adult authors and is intended to inspire youths in a way of moral development. The protagonist begins the story as someone of questionable morality, and finishes the piece a considerable more moral person. It has been made to help others learn about things such as discrimination, racism, and sexism. This novel also includes issues such as bullying and questioning of sexual orientations. This novel is meant to focus on the idea that a person is made up of the experiences he/she has endured- both the good and the bad

Tracking Cluster Debris (TraCD) – I. Dissolution of clusters and searching for the solar cradle

The capability to reconstruct dissolved stellar systems in dynamical and chemical space is a key factor in improving our understanding of the evolution of the Milky Way. Here we concentrate on the dynamical aspect and given that a significant portion of the stars in the Milky Way have been born in stellar associations or clusters that have lived a few Myr up to several Gyr, we further restrict our attention to the evolution of star clusters. We have carried out our simulations in two steps: (1) we create a simulation of dissolution and mixing processes which yields a close fit to the present-day Milky Way dynamics and (2) we have evolved three sets of stellar clusters with masses of 400, 1000 and 15 000 M⊙ to dissolution. The birth location of these sets was 4, 6, 8 and 10 kpc for the 400 and 1000 M⊙ clusters and 4, 6, 8, 10 and 12 kpc for the 15 000 M⊙. We have focused our efforts on studying the state of the escapers from these clusters after 4.5 Gyr of evolution with particular attention to stars that reach the solar annulus, i.e. 7.5 ≤ Rgc ≤ 8.5 kpc. We give results for solar twins and siblings over a wide range of radii and cluster masses for two dissolution mechanisms. From kinematics alone, we conclude that the Sun was ∼50 per cent more likely to have been born near its current Galactocentric radius, rather than have migrated (radially) ∼2 kpc since birth. We conclude our analysis by calculating magnitudes and colours of our single stars for comparison with the samples that the Gaia, Gaia-ESO and GALAH-AAO surveys will obtain. In terms of reconstructing dissolved star clusters, we find that on short time-scales we cannot rely on kinematic evolution alone and thus it will be necessary to extend our study to include information on chemical space

Low-energy electron diffraction investigation of epitaxial growth: Pt and Pd on Pd(100)

We investigate the epitaxial growth of Pt and Pd on Pd(100) via spot profile analysis using conventional low-energy electron diffraction (LEED). Despite the limited transfer width of our instrument (ca. 160 A) we resolve a central-spike and diffuse component in the spot profiles, reflecting the layer-occupations and pair-correlations, respectively;Kinetic limitations inhibit layer-by-layer growth at low temperatures. Our data suggest diffusion switches on at ca. 150 K for Pt and ca. 170 K for Pd indicating activation barriers to surface diffusion of ca. 10 and ca. 13 kcal/mol, respectively. We observe intensity oscillations of the central-spike, analogous to those measured via RHEED during MBE, even at substrate temperatures below which surface diffusion is appreciably operative. To clarify the role of diffusion in determining the resulting film morphology, we develop a growth model that incorporates the adsorption-site requirement. Our model predicts intensity oscillations, even in the absence of diffusion. The effect of diffusion is quite complex, since lateral diffusion leads to clustering, making growth less layer-by-layer like, yet interlayer diffusion generally enhances the layer-by-layer quality of the growth;Above ca. 250 K, overlayer reconstruction and/or dissolution interferes with the development of pseudomorphic layers of Pt on Pd(100). We study the homoepitaxy of Pd in a wider temperature range. In-phase LEED data suggest that in the limit of very small islands (one to a few atoms) the interlayer spacing is dependent on the number of atoms in an island. We present a new procedure to experimentally determine out-of-phase scattering conditions. At these energies, ring-structure is evident in the profiles during Pd growth between ca. 200 and 400 K. The appearance of ring-structure is correlated with the onset of diffusion. We report ring intensity oscillations as a function of coverage, which demonstrate the filling of individual layers. Growth at higher temperatures (ca. 500 K) results in step propagation , wherein deposited atoms generally migrate to existing step edges between deposition events, and nucleation of new layers proceeds only on very large terraces