On the heavy-tailedness of Student's tt-statistic

Let $\{X_i\}_{i\geq1}$ be an i.i.d. sequence of random variables and define, for $n\geq2$, T_n=\cases{n^{-1/2}\hat{\sigma}_n^{-1}S_n,\quad \hat{\sigma}_n>0,\cr 0,\quad \hat{\sigma}_n=0,}with S_n=\sum_{i=1}^nX_i, \hat{\sigma}^2_n=\frac{1}{n-1}\sum_{i=1}^n(X_i-n^{-1}S_n)^2. We investigate the connection between the distribution of an observation $X_i$ and finiteness of $\mathrm{E}|T_n|^r$ for $(n,r)\in \mathbb{N}_{\geq2}\times\mathbb{R}^+$. Moreover, assuming $T_n\stackrel{d}{\longrightarrow}T$, we prove that for any $r>0$, $\lim_{n\to\infty}\mathrm{E}|T_n|^r=\mathrm{E}|T|^r<\infty$, provided there is an integer $n_0$ such that $\mathrm {E}|T_{n_0}|^r$ is finite.Comment: Published in at http://dx.doi.org/10.3150/10-BEJ262 the Bernoulli (http://isi.cbs.nl/bernoulli/) by the International Statistical Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm

Generation of surface plasmons by electron beam excitation

We report on the first demonstration of excitation of propagating surface plasmon polaritons (SPPs) by injection of a beam of free electrons on an unstructured metal interface, providing a highly localized and intense source of plasmon waves. The plasmons were detected by a grating-assisted decoupling into light at a set of distances from the excitation point. This technique allows the high-resolution mapping of plasmon and photon emission from metal nanostructures

Visual Servoing for Floppy Robots Using LWPR

We have combined inverse kinematics learned by LWPR with visual servoing to correct for inaccuracies in a low cost robotic arm. By low cost we mean weak inaccurate servos and no available joint-feedback. We show that from the trained LWPR model the Jacobian can be estimated. The Jacobian maps wanted changes in position to corresponding changes in control signals. Estimating the Jacobian for the first iteration of visual servoing is straightforward and we propose an approximative updating scheme for the following iterations when the Jacobian can not be estimated exactly. This results in a sufficient accuracy to be used in a shape sorting puzzle.

Consequenses of a reindeer husbandry adapted forestry within a forest owner perspective

Inom större delen av norra Sverige verkar renskötsel och skogsbruk på samma marker, denna kombination av markutnyttjande kan i vissa fall leda till konflikter på grund av skogsbrukets påverkan på renens vinterbete. För att föra fram samernas talan har Svenska Samernas riksförbund gett ut policyprogrammet ”Ett renskötselanpassat skogsbruk” som ger förslag till anpassningar av skogsbrukets skötselåtgärder. Syftet med denna studie var att undersöka hur enskilda skogsägares ekonomi och möjligheter att producera virke påverkades vid en anpassning till detta policyprogram. Arbetet utfördes med hjälp av Heurekas applikation BeståndsVis genom att jämföra tre olika scenarier, med olika anpassningsgrad till policyprogrammet, på en lavrik tallmark med ståndortsindex T16 över en omloppstid. Beståndet ansågs återspegla en typisk vinterbetesmark för ren längs Öreälven inom Lycksele kommun. Det intensiva skogsbruket med contortatall gav den högsta avkastningen, men det renskötselanpassade skogsbruket lönade sig ändå bättre än det standardiserade, samt gav det högsta nettot vid föryngringsavverkning. Man kan däremot ifrågasätta föryngringskostnaderna i det renskötselanpassade skogsbruket, i och med att plantering utan markberedning inte gav en lägre plantöverlevnad, vilket inte framkommer i prognoser med BeståndsVis.Within most parts of northern Sweden reindeer husbandry and forestry works on the same type of land, this combination of land-use can in some cases lead to conflicts, because of the effects of forestry on areas used for winter grazing. In purpose to bring forward the Sámi peoples voice, the Swedish association of Sámi has given out the policy program “Ett renskötselanpassat skogsbruk” which gives suggestions for adaptions of the forestry’s management methods. The objective with this study was to investigate how a private forest owner’s economy and opportunities to produce wood for the industry, would be affected by an adaption to this policy program. The work was performed with the Heureka application StandWise by comparing three different scenarios, with different degrees of adaption to the policy program, on a lichen rich stand with Scots Pine for one rotation period. The stand was considered to represent a typical location for reindeer grazing during winter a long Öre river in Lycksele municipality. The intense forestry with lodgepole pine gave the highest revenue for one rotation period, but the reindeer adapted forestry paid off better than the standard type of forestry and gave the highest net income in clear-cutting. There are some parts of this study that can be questioned; e.g. the high plant survival in the reindeer adapted forestry which was unaffected by the fact that no scarification was applied

Fremont-Smith: The Foundations and Government: State and Federal Law and Supervision

Digimergo är en digitalisering av Emergo Train System, ett system där personal inom räddningstjänst kan öva på olika katastrofscenarion. För att göra Digimergo användbart behövdes ytterligare programvara: ett administrationsverktyg till övningar och en scenarioeditor. I det programvaruutvecklingsprojekt som denna rapport behandlar har ny programvara utvecklats och integrerats med det ursprungliga Digimergosystemet. I den här rapporten diskuteras vilka risker som existerar när ny funktionalitet skall läggas till ett gammalt projekt samt hur dessa risker kan minimeras. Rapporten undersöker också vilka utvecklingsmetoder som lämpar sig i projekt där ny funktionalitet ska läggas till befintliga system. Resultatet visar att den största risken med att utöka befintliga projekt är att underskatta tiden som krävs för att sätta sig in i projektet i fråga. Det mest effektiva sättet att minimera risken för detta är att mycket tidigt studera det tidigare arbetet och utbilda projektmedlemmarna i det gamla systemet. Ett annat angreppssätt är att välja en metod som är flexibel när det kommer till nya risker eller ändringar i projektets plan, förslagsvis iterativa metoder

Achieving accurate FTIR measurements on high performance bandpass filters

The sources of ordinate error in FTIR spectrometers are reviewed with reference to measuring small out-of-band features in the spectra of bandpass filters. Procedures for identifying instrumental artefacts are described. It is shown that features well below 0.01%T can be measured reliably

To what extent does surrounding landscape explain stand-level occurrence of conservation-relevant species in fragmented boreal and hemi-boreal forest?-a systematic review protocol

Background: Silviculture and land-use change has reduced the amount of natural forest worldwide and left what remains confined to isolated fragments or stands. To understand processes governing species occurrence in such stands, much attention has been given to stand-level factors such as size, structure, and deadwood amount. However, the surrounding matrix will directly impact species dispersal and persistence, and the link between the surrounding landscape configuration, composition and history, and stand-level species occurrence has received insufficient attention. Thus, to facilitate optimisation of forest management and species conservation, we propose a review addressing 'To what extent does surrounding landscape explain stand-level occurrence of conservation-relevant species in fragmented boreal and hemi-boreal forest?'.Methods: The proposed systematic review will identify and synthesise relevant articles following the CEE guidelines for evidence synthesis and the ROSES standards. A search for peer-reviewed and grey literature will be conducted using four databases, two online search engines, and 36 specialist websites. Identified articles will be screened for eligibility in a two-step process; first on title and abstract, and second on the full text. Screening will be based on predefined eligibility criteria related to a PECO-model; population being boreal and hemi-boreal forest, exposure being fragmentation, comparator being landscapes with alternative composition, configuration, or history, and outcome being occurrence (i.e., presence and/or abundance) of conservation-relevant species. All articles that pass the full-text screening will go through study validity assessment and data extraction, and be part of a narrative review. If enough studies prove comparable, quantitative meta-analyses will also be performed. The objective of the narrative review and the meta-analyses will be to address the primary question as well as six secondary questions, and to identify important knowledge gaps