322,966 research outputs found
Election Forecasting Techniques - Part I
No full textThis is the first of two special issues devoted to current topics and innovative approaches in the field of election forecasting techniques. The articles included in these special issues were submitted to the journal after a call for papers was circulated in mid-2013, soliciting contributions that advance the current state of the literature and/or promote novel approaches to political opinion polling, with special emphasis on uses of forecasting techniques of election results.
The articles hosted in the two issues cover topics ranging from exit polls, explanatory statistical models based on structural variables (economic trends, government approval ratings, etc.), prediction markets, social media-based election forecasting, the web as a means to collect data on voting preferences, and measures
of forecast accuracy.
In the first contribution appearing in this issue, titled “Evolving approaches to election forecasting” (the only invited article), Jocelyn Evans examines major approaches to electoral forecasting and discusses their distinctive traits and the constraints which render them variably useful in specific research contexts. He also
addresses the growing use of forecasting tools, stressing the need to adapt techniques originally developed in order to achieve other goals and to not lose track of researchers’ major purpose when employing these techniques, which is to say a greater comprehension of how elections actually work.
As regards prediction markets, an interesting article submitted to the journal is “Accuracy and bias in European prediction markets”, by Sveinung Arnesen and Oliver Strijbis. The paper describes how prediction markets work, specifically the Iowa Electronic Markets (IEM), and provides a meta-analysis of the scores from 62 prediction market vote share contracts for elections in Switzerland, Germany, and Norway. The aim of the paper is to uncover potential biases in forecasting by comparing them with the actual results. The authors show that there is an aggregate bias in the predictions: the actual outcomes tend to have more extreme values than predicted, so that European prediction markets would be biased. Specifically, they show that small-sized vote share contracts tend to be overpredicted, and large-sized vote share contracts tend to be underestimated. The major result reported in this contribution appears to invite researchers to a cautious use of the logarithmic market scoring rule (LMSR) as an automated market maker in vote share markets.
In “Assessing correct voting: A study based on a simulation of municipal elections in Italy”, Giancarlo Gasperoni and Debora Mantovani offer an empirical application of “correct voting” to the Italian political system. The authors estimate correct voting using data collected through the development of an on-line simulation of an Italian election campaign implemented via a “dynamic process-tracing environment”. A typology of voting behaviour is then proposed which combines both correct voting models and the traditional approach distinguishing between political subculture belonging and opinion-based voting among Italian voters. Four multinomial logistic regression models are developed in which the dependent variable is the above-mentioned typology of voting behaviour; the authors use these models to test hypotheses on voting behaviour according to which voters are more likely to vote “correctly” if they express high levels of interest in politics and high degrees of political competence, and if they are “active” seekers of information during the simulated election campaign. Findings show that voters are more likely to vote correctly if they express higher levels of interest in politics, but the effect of political competence is statistically insignificant. Moreover, voters are not more likely to vote correctly if they are “generally active” seekers of flow items concerning candidates’ issues orientations, but they are more likely to vote correctly if they are “specific active” seekers of information concerning their “correct” candidates’ issue orientations.
A further article deals with “Forecasting elections with high volatility”, by Antonio F. Alaminos. In the article, Alaminos proposes the use of a combination of aggregated electoral data from the 1994 German Bundestag elections and the 1998 German Allbus social survey to estimate four probabilistic models of forecasting the German 1998 general elections. The models are built following the logic of Markov chains which, according to the author, make it possible to account for the large electoral volatility observed in the German elections across the 1990s. The forecasts based on the four models perform better than those provided by other techniques, in terms of predicting the winning party and the position of the second and third parties. In addition, the author demostrates that, among the four proposed models, the two corrected models – which assume that there are restrictions to electoral mobility – behave better than the two other pure Markov chain models, which assume that all voters can change their electoral choice.
This first issue of the double-issue set concludes with contributions drawn from a round table discussion dedicated to election forecasting, which took place on February 15, 2013, in Milan during a national conference on “The Value of Statistics for Businesses and Society: Opinion and Market Research” promoted by the Association for Applied Statistics (ASA), the Association for Market, Social, and Opinion Research (ASSIRM), the Italian Statistics Society (SIS), and the Catholic University of the Sacred Heart of Milan
Election Forecasting: A Roundtable Discussion
No full textOn the 14th and 15th of February, 2013, in Milan, the Association for Applied Statistics (ASA), the Association for Market, Social, and Opinion Research (ASSIRM), the Italian Statistics Society (SIS), and the Catholic University of the Sacred Heart of Milan promoted a national conference on “The Value of Statistics for Business and Society: Opinion and Market Research”. The conference ended with a round table discussion dedicated to “Election Forecasting”, moderated by the ASA President B. Vittorio Frosini. The round table participants included Renato Mannheimer, Maurizio Pessato, Giancarlo Gasperoni, and Stefano M. Iacus. The text provides a summary of each speaker’s comments, in some cases integrated with observations regarding more recent events. The text is part of a special issue dedicated to "Election Forecasting"
Copper(II) ions in organic synthesis. II1. Regeneration of carbonyl compounds from tosylhydrazones by hydrolysis in the presence of cupric sulphate pentahydrate
No full textEffect of copper(II) ions in organic synthesis. III. Regeneration of carbonyl compounds from some derivatives by hydrolysis in the presence of copper(II) ions
No full textSpecial Issues on "Election Forecasting Technqiues (Part II)" - Editorial
No full textShort introduction to co-edited special issue
Effect of copper(II) ions in organic synthesis. V. Regeneration of carbonyl compounds from tosylhydrazones, phenylhydrazones, hydrazones, oximes and semicarbazones by hydrolysis in the presence of copper(II) sulphate pentahydrate
No full textVoting Intention Polls in the 2019 Italian Election for the European Parliament: Methodological Quality and Predictive Capacity in Times of Populism
No full textIn May 2019, the European Parliamentary (EP) elections will take place and one year will have passed since the investiture of Italy’s current, and contentious, coalition government, sustained by an unlikely and unsteady alliance between the League (the ostensibly junior partner) and the Five-Star Movement. The government's patent populist policies and its leaders’ relentless social media campaigning have apparently engendered exceptionally high levels of public support. Current vote forecasts are favourable for both parties (but extremely so for the League); these expectations are noticeably driving policy decisions, shaping the balance of power between the two allies, fanning their Euroscepticism, and affecting the likelihood of the government’s survival until the EP election. Since Italian pollsters’ markedly failed to anticipate practically all of the most politically relevant outcomes of the 2018 national elections and significantly underestimated the strength of the two currently governing parties, it is legitimate to wonder whether current polls are reliable, i.e., whether pollsters are collectively “overcompensating” for last year’s failures and thus likely to perform badly once again. The paper intends to monitor the methodological quality (especially vis-à-vis past election campaigns) of published polls carried out during the 2019 EP election campaign in Italy (administration mode, sample size, sampling technique, weighting procedures, etc.). Moreover, polls’ predictive capacity will be assessed (primarily via examination of voter turnout expectations and, for the relationships between competing parties, via Martin et al.’s “A” measure); characteristics of better-performing polls will be identified and discussed. The role of published voting intention polls and the impact of rules regulating published polls in Italy (especially its two-week embargo) will also be explored
Towards New Hypergolic Hydrogen Peroxide-Based Bipropellants
No full textHydrogen peroxide in combination with hydrocarbons, alcohols, or amines can be considered an attractive solution for the development of storable bipropellant candidates replacing hydrazine. The non-hypergolic nature of these couples imposes the use of a mechanism of ignition, though. This raises concerns of reliability when multiple firings are planned. A modified fuel composition, demonstrating hypergolic ignition capability with hydrogen peroxide, has been recently tested at the SPLab of Politecnico di Milano. The fuel is based on ethanolamine, ethanol and a copper-based additive. The experimental test campaign has demonstrated the efficacy of the ignition process, granting an ignition delay time down to 34 ms. A parametric analysis on additive and fuel combination will be presented
Un miglioramento immeritato? La capacità predittiva dei sondaggi preelettorali e le elezioni del 2008
No full textI risultati delle elezioni parlamentari italiane del 2006 erano così incerti che nessun sondaggio pre-elettorale avrebbe potuto prevderli con precisione. In un lavoro precedente degli stessi autori, l'uso di un indice di capacità predittività - l'A di Martin e collaboratori - in relazione ai sondaggi pre-elettorali del 2001 e del 2006 aveva mostrato che questi avevano avuto prestazioni deludenti e sovrastimato i consensi per le coalizioni vincenti. In questo nuovo lavoro gli stessi autori prendono in esame i sondaggi pre-elettorali riferiti alle elezioni politiche del 2008. Nonostante diversi fattori che avrebbero potuto inficiare la capacità predittiva dei sondaggi - fra cui labrevità della campagna elettorale, una significativa ristrutturazione delle coalizioni elettorali, una diversa rilevanza dei partiti minori esclusi dalle maggiori coalizioni, l'ulteriore crescita della quota di famiglie non dodtate di utenze telefoniche di rete fissa e l'accresciuto astensionismo -- e a dispetto dell'aggravamento di alcuni problemi metodologici attinenti ai sondaggi medesimi, la capacità predittiva è migliorata rispetto al 2001 e al 2006, Inoltre, gli autori propongono un uso innovativo di A, per valutare le prestazioni dei sondaggi in merito all'allocazione dei voti *entro* le coalizioni di centro-destra e di centro-sinistra.Two years have passed since the last Italian parliamentary elections, the results of which were so close that no pre-election poll could have reliably predicted the winner. In preceding work by the two authors, a measure of predictive accuracy - Martin et al.'s A - was applied to the 2006 and 2001 Italian general elections and showed that in both instances published polls performed badly and overestimated voters' support for the winning coalition. In this new article, the authors monitor the performance of published polls conducted during the 2008 election campaign. The polls' predictive accuracy could have been further impaired, with respect to the past, by several factors: the relative brevity of the campaign; a comprehensive re-structuring of electoral alliances; the ensuing need for voters to adapt to the new scenario; the renewed relevance of smaller parties excluded from the major electoral alliances, thereby weakening the election's "bipolar" structure; an increasing telephoneinterviewing coverage error due to the high incidence of households having only mobile phones or no phone; decreasing voter turnout. Despite these potential problems and published surveys' several methodological shortcomings, predictive accuracy improved with respect to 2001 and 2006. The authors also use A in an innovative way, i.e., to assess polls performance regarding the allocation of votes within the centre-left and the centre-right coalitions
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