987 research outputs found
Obergefell’s Missed Opportunity
The stock market plays a big role in our current nancial system and the uctuations onit are believed to depend on many dierent factors. One of the factors that are believedto be correlated to the stock market are macroeconomic variables, that is, variables thatindicate the status of the economical situation. Examples of such macroeconomic variablesare unemployment rate, loan interests and ination. Earlier attempts to predictthe stock market have been made by using process demanding methods such as arti-cial neural network. A multilayer perceptron is a self learning system that goes underthe category of an articial neural network. Such a network learns by being trainedon old data sets and has the capacity to identify relationships between dierent data.This method has been used in earlier studies to predict the stock market with goodresults. The problem statement of this report is to nd the optimal training interval fora multilayer perceptron on a day to day estimation of the Swedish OMXS30 index. Theinput to the algorithm consisted of 38 parameters, which in this case was a collectionof individual companies stock prices, foreign stock indexes, macroeconomic variables,previous and current values of the OMXS30 index. The results from the simulationsthat were executed on old stock data shows that 180 to 200 days of training yielded thebest results, where eight of nine periods over seven years (2007-2014) yielded prot. Theresults from the simulations during the periods with increasing index were sometimesbelow the index gain, but always with a prot. During periods of index decrease theresults were sometimes with a prot and sometimes non-prot. In the case of indexdecrease the result was always above the total index decrease. The conclusion is as theresults shows, that the optimal training interval is 180 to 200 days for the simulationsrun in the study of this report.1Aktiemarknaden spelar en stor roll i dagens finansiella system och fluktutionerna på börsen tros bero pa många orsaker. En av de saker som tros ha en koppling till börsen är makroekonomiska variabler, dvs sådana variabler som indikerar hur ekonomin mår. Exempel på makroekonomiska variabler ar arbetslöshet, räntenivåer och i nation. Andra kopplingar som tros finnas till börsens utveckling är hur individuella aktier och utlandskabörser utvecklas. Tidigare försök har gjorts att forsöka forutsäga aktiemarknaden med hjalp av beräkningskrävande metoder, t. ex. Articiella neuron nät. En flerlagers perceptronar ett självlärande system som räknas som en typ av articiellt neuron nät. Nätverket lär sig genom att tränas pa gammal data och har formåagan att hitta samband mellan olika data. I tidigare studier har denna metod använts for att förutsäga aktiemarknaden med goda resultat. Problemformulering i denna rapport ar att ta reda på vilket det optimala träningsintervallet ar för en flerlagers perceptron för att, från en dag till en annan, förutsäga indexet på Stockholmsbörsen, OMXS30. Algoritmens indata bestod av totalt 38 parametrar som i detta fall var en samling av enskilda företagsaktievärden, utländska börsers index, makroekonomiska variabler, tidigare värden på OMXS30 samt det nuvarande värdet pa börsen. Resultaten från simulationerna som kördes pa gammal aktiedata visar att 180-200 dagar är det basta träningsintervallet daatta av nio stycken perioder över sju år (2007-2014) gick med vinst. Resultaten fransimulationerna under de perioder med stigande index blev i vissa fall under index, men alltid med vinst. I perioder med avtagande index sa blev resultaten i vissa fall vinstgivande och i andra fall inte vinstgivande, men i dessa fall alltid battre an den totalaindex nedgangen. Slutsatsen ar som resultaten visar att 180-200 dagar ar det optimala träningsintervallet for de simulationer som gjordes i undersökningen i denna rapport.
Simple Bayesian testing of scientific expectations in linear regression models
Scientific theories can often be formulated using equality and order
constraints on the relative effects in a linear regression model. For example,
it may be expected that the effect of the first predictor is larger than the
effect of the second predictor, and the second predictor is expected to be
larger than the third predictor. The goal is then to test such expectations
against competing scientific expectations or theories. In this paper a simple
default Bayes factor test is proposed for testing multiple hypotheses with
equality and order constraints on the effects of interest. The proposed testing
criterion can be computed without requiring external prior information about
the expected effects before observing the data. The method is implemented in
R-package called `{\tt lmhyp}' which is freely downloadable and ready to use.
The usability of the method and software is illustrated using empirical
applications from the social and behavioral sciences.Comment: 33 pages, 1 figure, 2 appendice
The green economy and the Nordic welfare state : Reconceptualizing green economy narratives from a Nordic perspective
The green economy with its aim to combine ecological and economic objectives has gained in both significance and political contestation in recent years. In this working paper for the NOWAGG project we revisit the literature on the green economy to understand its implications from a Nordic perspective. Our ambition is to improve the conceptualization of different approaches to green the economy by subjecting them to often overlooked aspects relevant to the Nordic welfare states, including dimensions of innovation as well as social welfare. By conducting a literature review and making use of narrative policy analysis we demonstrate that a binary division, common in the academic literature and policy debate, is insufficient to grasp the nuances of the green economy. We arrive in the finding that not only ‘green growth’ and ‘beyond growth’ narratives are prevalent in academic and policy literature but also a reformist narrative in-between these two; what we refer to as a ‘transformative green economy’ narrative.This is of importance for the Nordic welfare state which arguably have the potential to incorporate a ‘third way’ to sustainable development and for greening the economy. Building on this insight and Nordic welfare state literature we suggest a conceptual framework for the economy of the green Nordic welfare state, a revised reformist narrative on the green economy. Empirically, however, the welfare states are confronted by numerous challenges and ongoing liberal transformations. Thus, it remains for future studies to conclude which green economy path the Nordic states will take and how that will affect the prospects for achieving inclusive, long-term welfare while respecting ecological limits
En majoritet av minoriteten - En intervjustudie som söker förståelse för den hazariska invandringen till Europa
In this thesis I seek to understand why a majority of the Afghans that have migrated to Europe during the last decade belong to the Hazara ethnicity. Reports claim that the situation has improved dramatically for the minority since the fall of Taliban in 2001 and there is currently no legal opportunity for refuge on the basis of ethnicity. The common understanding of security as the major driver for conflict migration consequently seem insufficient. By broadening the security approach and seeking answers in the migration theories of social networks and New Economics of Labour Migration this study enables us to further understand this seemingly enigmatic migration pattern. The method for reaching this understanding is conducting interviews with both Hazaras that have migrated and with a country-of-origin expert. When analyzing the interviews, a multifaceted migration decision becomes apparent. To understand the disproportionate migration pattern, a broader security perspective, encompassing historical traumas and discrimination, along with acknowledging the networks influence as both the cause and facilitator of further migration, is needed. In relating this to the abstract question of why people are migrating, this study promotes the continuing focus on intentions in the migration decisions to comprehend the puzzling migration patterns of the future
Модифицированные стеклопорошки для практических приложений в электронике: технология получения и управление свойствами
Материалы XV Междунар. науч.-техн. конф. студентов, аспирантов и молодых ученых, Гомель, 23–24 апр. 2015 г
Heterogeneity in direct replications in psychology and Its association with effect size
We examined the evidence for heterogeneity (of effect sizes) when only minor changes to sample population and settings were made between studies and explored the association between heterogeneity and average effect size in a sample of 68 meta-analyses from 13 preregistered multilab direct replication projects in social and cognitive psychology. Among the many examined effects, examples include the Stroop effect, the "verbal overshadowing" effect, and various priming effects such as "anchoring" effects. We found limited heterogeneity; 48/68 (71%) meta-analyses had nonsignificant heterogeneity, and most (49/68; 72%) were most likely to have zero to small heterogeneity. Power to detect small heterogeneity (as defined by Higgins, Thompson, Deeks, & Altman, 2003) was low for all projects (mean 43%), but good to excellent for medium and large heterogeneity. Our findings thus show little evidence of widespread heterogeneity in direct replication studies in social and cognitive psychology, suggesting that minor changes in sample population and settings are unlikely to affect research outcomes in these fields of psychology. We also found strong correlations between observed average effect sizes (standardized mean differences and log odds ratios) and heterogeneity in our sample. Our results suggest that heterogeneity and moderation of effects is unlikely for a 0 average true effect size, but increasingly likely for larger average true effect size
Meta-analyzing the multiverse:A peek under the hood of selective reporting
Researcher degrees of freedom refer to arbitrary decisions in the execution and reporting of hypothesis-testing research that allow for many possible outcomes from a single study. Selective reporting of results ( p-hacking) from this “multiverse” of outcomes can inflate effect size estimates and false positive rates. We studied the effects of researcher degrees of freedom and selective reporting using empirical data from extensive multistudy projects in psychology (Registered Replication Reports) featuring 211 samples and 14 dependent variables.We used a counterfactual design to examine what biases could have emerged if the studies (and ensuing meta-analyses) had not been preregistered and could have been subjected to selective reporting based on the significance of the outcomes in the primary studies. Our results show the substantial variability in effect sizes that researcher degrees of freedom can create in relatively standard psychological studies, and how selective reporting of outcomes can alter conclusions and introduce bias in meta-analysis. Despite the typically thousands of outcomes appearing in the multiverses of the 294 included studies, only in about 30%of studies did significant effect sizes in the hypothesized direction emerge.We also observed that the effect of a particular researcher degree of freedom was inconsistent across replication studies using the same protocol, meaning multiverse analyses often fail to replicate across samples.We recommend hypothesis-testing researchers to preregister their preferred analysis and openly report multiverse analysis. We propose a descriptive index (underlying multiverse variability) that quantifies the robustness of results across alternative ways to analyze the data.</p
Att reformera i NPM-anda - En studie om demokrativärdenas beaktande vid implementerandet av lean i svensk sjukvård
Den offentliga förvaltningen utgör ett viktigt möte mellan stat och samhällsmedlem. Det är därför viktigt att de värdegrunder vilka förvaltningen arbetar efter beaktas. Genom en intervju med en fokusgrupp bestående av fem personer anställda inom sjukvården har vi undersökt på vilka värdegrunder denna del av förvaltningen arbetar mot. I relation till detta har vi använt oss av Lennart Lundquists teori om vårt offentliga etos där han pekar på vilka värden förvaltningens arbete bör bygga på. Resultatet av undersökningen har visat på att alla de värden som borde tas i beaktande i offentlig verksamhet inte får det utrymme som de borde, detta på grund av ett allt för stort fokus på den ekonomiska aspekten
Two-loop amplitudes for t t ¯ H production: the quark-initiated N f -part
We present numerical results for the two-loop virtual amplitude entering the NNLO corrections to Higgs boson production in association with a top quark pair at the LHC, focusing, as a proof of concept of our method, on the part of the quark-initiated channel containing loops of massless or massive quarks. Results for the UV renormalised and IR subtracted two-loop amplitude for each colour structure are given at selected phase-space points and visualised in terms of surfaces as a function of two-dimensional slices of the full phase space
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