The Signal and the Noise: Why So Many Predictions Fail--But Some Dont Pdf, Epub, Ebook
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Psephological Fallacies of Public Opinion Polling
SPECIAL ARTICLE Psephological Fallacies of Public Opinion Polling Praveen Rai Opinion polls in India capture electoral snapshots in time he terms “survey” and “opinion poll” in India would that divulge information on political participation, have remained a professional jargon of market research industry, had it not been used for predicting election ideological orientation of voters and belief in core T outcomes. The green shoots of opinion polls to study Indian democratic values. The survey data provides for crucial national elections emerged in the 1950s, but it caught the ima- social science insights, validation of theoretical research gination of the people and became clichéd in the closing dec- and academic knowledge production. Although the ade of the 20th century. The popularity of election surveys stems from the political socialisation and crystal ball gazing media’s obsession with political forecasting has shifted curiosity of Indians to foresee the outcomes of hustings before to electoral prophecy, psephology continues to provide the pronouncement of formal results. The electoral inquisitive- the best telescopic view of elections based on the ness of the stakeholders created a large canvas of opportunity feedback of citizens. The ascertainment of subaltern for opinion-polling industry and scope for scientifi c forecasting of Indian election competitions. The proliferation of electronic opinion by surveys not only broadens the contours of media and the rapid monetisation in the 1990s provided mo- understanding electoral democracy, but also provides mentum to polling agencies to venture into opinion polling on an empirical alternative to the elitist viewpoint of national electoral politics and state election contests. The opin- competitive politics in India. -
Forecasting Elections: Voter Intentions Versus Expectations*
Forecasting Elections: Voter Intentions versus Expectations* David Rothschild Justin Wolfers Microsoft Research Dept of Economics and Ford School of Public Policy, and Applied Statistics Center, Columbia University of Michigan Brookings, CEPR, CESifo, IZA and NBER [email protected] [email protected] www.ResearchDMR.com www.nber.org/~jwolfers Abstract Most pollsters base their election projections off questions of voter intentions, which ask “If the election were held today, who would you vote for?” By contrast, we probe the value of questions probing voters’ expectations, which typically ask: “Regardless of who you plan to vote for, who do you think will win the upcoming election?” We demonstrate that polls of voter expectations consistently yield more accurate forecasts than polls of voter intentions. A small-scale structural model reveals that this is because we are polling from a broader information set, and voters respond as if they had polled twenty of their friends. This model also provides a rational interpretation for why respondents’ forecasts are correlated with their expectations. We also show that we can use expectations polls to extract accurate election forecasts even from extremely skewed samples. This draft: November 1, 2012 Keywords: Polling, information aggregation, belief heterogeneity JEL codes: C53, D03, D8 * The authors would like to thank Stephen Coate, Alex Gelber, Andrew Gelman, Sunshine Hillygus, Mat McCubbins, Marc Meredith and Frank Newport, for useful discussions, and seminar audiences at AAPOR, Berkeley, Brookings, CalTech, Columbia, Cornell, the Conference on Empirical Legal Studies, the Congressional Budget Office, the Council of Economic Advisers, Harvard, Johns Hopkins, Maryland, Michigan, MIT, the NBER Summer Institute, University of Pennsylvania’s political science department, Princeton, UCLA, UCSD, USC, and Wharton for comments. -
Citizen Forecasts of the 2008 U.S. Presidential Election
bs_bs_banner Citizen Forecasts of the 2008 U.S. Presidential Election MICHAEL K. MILLER Australian National University GUANCHUN WANG Lightspeed China Ventures SANJEEV R. KULKARNI Princeton University H. VINCENT POOR Princeton University DANIEL N. OSHERSON Princeton University We analyze individual probabilistic predictions of state outcomes in the 2008 U.S. presidential election. Employing an original survey of more than 19,000 respondents, we find that partisans gave higher probabilities to their favored candidates, but this bias was reduced by education, numerical sophistication, and the level of Obama support in their home states. In aggregate, we show that individual biases balance out, and the group’s predictions were highly accurate, outperforming both Intrade (a prediction market) and fivethirtyeight.com (a poll-based forecast). The implication is that electoral forecasters can often do better asking individuals who they think will win rather than who they want to win. Keywords: Citizen Forecasts, Individual Election Predictions, 2008 U.S. Presidential Election, Partisan Bias, Voter Information, Voter Preference, Wishful Thinking Bias in Elections. Related Articles: Dewitt, Jeff R., and Richard N. Engstrom. 2011. The Impact of Prolonged Nomination Contests on Presidential Candidate Evaluations and General Election Vote Choice: The Case of 2008.” Politics & Policy 39 (5): 741-759. http://onlinelibrary.wiley.com/doi/10.1111/j.1747-1346.2011.00311.x/abstract Knuckey, Jonathan. 2011. “Racial Resentment and Vote Choice in the 2008 U.S. Presidential Election.” Politics & Policy 39 (4): 559-582. http://onlinelibrary.wiley.com/doi/10.1111/j.1747-1346.2011.00304.x/abstract Politics & Policy, Volume 40, No. 6 (2012): 1019-1052. -
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US Presidential Elections: Why a Democrat is now favourite to win in 2020. The results of the US midterm elections are now largely in and they came as a shock to many seasoned forecasters. This wasn’t the kind of shock that occurred in 2016, when the EU referendum tipped to Brexit and the US presidential election to Donald Trump. Nor the type that followed the 2015 and 2017 UK general elections, which produced a widely unexpected Conservative majority and a hung parliament respectively. On those occasions, the polls, pundits and prediction markets got it, for the most part, very wrong, and confidence in political forecasting took a major hit. The shock on this occasion was of a different sort – surprise related to just how right most of the forecasts were. Take the FiveThirtyEight political forecasting methodology, most closely associated with Nate Silver, famed for the success of his 2008 and 2012 US presidential election forecasts. In 2016, even that trusted methodology failed to predict Trump’s narrow triumph in some of the key swing states. This was reflected widely across other forecasting methodologies, too, causing a crisis of confidence in political forecasting. And things only got worse when much academic modelling of the 2017 UK general election was even further off target than it had been in 2015. How did it go so right? So what happened in the 2018 US midterm elections? This time, the FiveThirtyEight “Lite” forecast, based solely on local and national polls weighted by past performance, predicted that the Democrats would pick up a net 38 seats in the House of Representatives. -
Ericka Menchen-Trevino
Ericka Menchen-Trevino 7/24/2020 c COPYRIGHT by Kurt Wirth July 23, 2020 ALL RIGHTS RESERVED PREDICTING CHANGES IN PUBLIC OPINION WITH TWITTER: WHAT SOCIAL MEDIA DATA CAN AND CAN'T TELL US ABOUT OPINION FORMATION by Kurt Wirth ABSTRACT With the advent of social media data, some researchers have claimed they have the potential to revolutionize the measurement of public opinion. Others have pointed to non-generalizable methods and other concerns to suggest that the role of social media data in the field is limited. Likewise, researchers remain split as to whether automated social media accounts, or bots, have the ability to influence con- versations larger than those with their direct audiences. This dissertation examines the relationship between public opinion as measured by random sample surveys, Twitter sentiment, and Twitter bot activity. Analyzing Twitter data on two topics, the president and the economy, as well as daily public polling data, this dissertation offers evidence that changes in Twitter sentiment of the president predict changes in public approval of the president fourteen days later. Likewise, it shows that changes in Twit- ter bot sentiment of both the president and the economy predict changes in overall Twitter sentiment on those topics between one and two days later. The methods also reveal a previously undiscovered phenomenon by which Twitter sentiment on a topic moves counter to polling approval of the topic at a seven-day interval. This dissertation also discusses the theoretical implications of various methods of calculating social media sentiment. Most importantly, its methods were pre-registered so as to maximize the generalizability of its findings and avoid data cherry-picking or overfitting. -
PDF Download the Signal and the Noise: Why So Many Predictions Fail
THE SIGNAL AND THE NOISE: WHY SO MANY PREDICTIONS FAIL--BUT SOME DONT PDF, EPUB, EBOOK Nate Silver | 560 pages | 03 Feb 2015 | Penguin Books | 9780143125082 | English | United States The Signal and the Noise: Why So Many Predictions Fail--But Some Dont PDF Book Basically, it's hard to predict stuff. The chance of getting a positive mammogram for a woman without cancer. Without any introduction to the subject, he claims Hume is stuck in some 'skeptical shell' that prevents him from understanding the simple, elegant solutions of Bayes. In almost every chapter following this he refers to the way that Bayesian reasoning can be used to strengthen forecasting and to overcome some of the difficulties of predicting in that area. Silver simply crunched the numbers and nailed the outcomes in every state. Vision and taste, for example, are perceptions derived from the brain's ability to discern pattern. It was published in Japanese in November One of my favorite tweets ever I don't read many tweets came from Ken Jennings on election morning of , something along t Reading Nate Silver is like exhaling after holding your breath for a really long time. Had this quote been from the introduction, and had the book given any insight into how to get beyond the platitudes, it would be the book I hoped to read. Silver's book, The Signal and the Noise , was published in September In respect of the financial crisis, he identifies various failures of prediction housing bubble, rating agencies, failure to see how it would cause a global financial crisis, failure to realise how big and deep recession would be which he largely ascribes to over-confidence and inability to forecast out of sample events.