立即打开
大选在即,两位候选人民调结果越来越接近

大选在即,两位候选人民调结果越来越接近

SHAWN TULLY 2020-11-03
美国总统大选将变得异常激烈,在选举夜之前将难分胜负。

不要低估特朗普。特朗普在搞砸了第一次辩论并感染新冠肺炎之后,他的胜选概率大降,但之后有大幅提高。这种上升的势头仍在继续,如果他的支持率继续按照这样的速度上升,美国总统大选将变得异常激烈,在选举夜之前将难分胜负。

这是西北大学(Northwestern University)数据科学家托马斯•米勒的研究结果。米勒创建了一种新方法,专门用于预测今年总统大选的结果。米勒告诉《财富》杂志:“特朗普重新开始他所擅长的造势活动之后,声望有所上升。本次大选的竞争异常激烈,双方的差距很小,但这并没有引起媒体的关注。你依旧会听到许多电视节目里大谈特谈拜登的压倒性优势,说他拿下了德克萨斯州。这是不可能的。”

米勒是西北大学数据科学项目的负责人。他曾经创建过一个类似的计算机模型,通过模拟击球手和投手之间的不同配对,预测职业棒球比赛的结果。他说该模型会模拟每一位球员的上场击球次数。“我会在正式比赛之前模拟整场比赛,看看谁能获胜,通过这种方式来确定赔率。然后我将这些赔率与博彩网站上的赔率相匹配,如果两个赔率的偏差很大,就是下注的时候。我发现在15场比赛中,可能有一两场值得下注。”

他在8月开始研究大选数据。但他并没有使用民意调查数据,或者经济状况对大选结果的影响等历史指标,尽管这是最常用的两种预测大选结果的工具。他的预测基于美国知名度最高的政治博彩网站PredictIt上发布的赔率。米勒认为,用政治赌客对候选人设定的“价格”作为指导,比受访者在接受民意调查机构的电话调查时所说的偏好更可靠。

米勒说:“投注市场提供的赔率最为可靠,因为当人们在某件事上投入真金白银的时候,你可以确信他们对这件事很有信心。如果网站上对特朗普的投注价格是40美分,拜登是60美分,而且你认为拜登胜选的概率超过0.6,你就会押注拜登。这是高效政治博彩市场的魅力所在。”米勒认为,政治期货网站能够最准确地预测“群体的智慧”。

他表示,民意调查问选民会把选票投给谁,其实是在问他们希望谁赢,“而PredictIt问的是:‘你相信谁会赢?’这个问题更一针见血。”他补充说,民意调查结果体现了几天前收集的意见,但没有体现候选人昨天的丑态,或者因为候选人在辩论中表现出色或糟糕所带来的支持率的巨大变化。他说:“我的预测结果比民意调查结果提前五天。我提前五天就知道第一次总统大选辩论的获胜者会是拜登。”民意调查结果发布的时候就已经过时。

米勒之所以信任PredictIt的赔率,是因为该网站对56个司法辖区的选举团票分别投注,包括48个“赢者通吃”的州、内布拉斯加州和缅因州的7个选区以及哥伦比亚特区。因此,他可以采用56个独立政治市场中每分钟的实时数据进行预测。他表示,PredictIt平台的流动性很高,因为该平台上有10万赌客,而且仅限于美国居民。这些人大都非常了解各县和各州本地基层的趋势导向。

他将这种方法命名为“Virtual Tout”,并在其网站上每小时更新一次预测结果。(或者通过推特账号@virtualtout发布。)米勒从PredictIt平台上提取各州市场不断变化的赔率,并把它们汇总成两个主要数据点:模型预测前副总统拜登将赢得的选举团票数,以及用百分比表示的拜登的胜选概率。米勒的网站上的一个曲线图代表了选举团票的趋势。经过米勒的方法筛选后,当PredictIt平台上各州投注窗口中的赔率更支持拜登时,曲线会上升。如果特朗普在56个地区的声望升高,就像现在一样,曲线就会下降。

图中还显示了导致选举团票数和胜选概率突然波动的重要事件。特朗普在《60分钟》(60 Minutes)节目中大发脾气或米歇尔•奥巴马在一条视频中发表了一通肺腑之言之后,这种方法在不到一个小时内显示,拜登的声望大幅提升。米勒说:“有时候我没有看新闻,但我发现时间序列出现大幅波动,然后我才会去看新闻,了解发生了什么。”

下面让我们回顾一下米勒的模型中,在第一阶段帮助拜登声望大涨的那些事件。米勒在8月初建立网站,并发现在整个8月份,围绕双方的竞选活动,拜登一直以80%至85%的胜选概率领先于特朗普(20%至15%)。到9月初,拜登依旧领先,模型预测他将获得约310张选举团票,但他要获胜还需要40张选票。从9月29日的第一次辩论开始,特朗普总统的选情变得更糟糕。米勒说:“特朗普搞砸了第一次辩论。一周后,他被确诊感染新冠病毒。我看到在消息公布之后一个小时内,拜登的选举团票数增加了四张。”这件事提醒美国人还有一场疫情正在威胁他们自身的健康和美国的经济。10月6日,特朗普神情憔悴地在沃尔特里德医院(Walter Reed)接受治疗,这时该模型预测拜登的选举团票达到326张,入主白宫的概率提高到94%。拜登似乎正在形成压倒性优势。

然后,情况发生了变化。在10月7日副总统辩论的当天,特朗普的势头开始反弹。但四天之后,《周六夜现场》(Saturday Night Live)的一段恶搞,让特朗普的上升势头戛然而止。这段喜剧节目也显示出米勒的模型对于选民情绪的快速变化极其敏感。这段节目恶搞了副总统辩论和落在彭斯头上的那只网红苍蝇,而正在与妻子吉尔观看这场辩论的拜登跳进了时间机器,变成了那只烦人的苍蝇,让人回想起电影《变蝇人》(The Fly)里变形的场面。米勒说:“从午夜左右到凌晨5点,拜登增加了多张选举团票。这肯定是因为《周六夜现场》里的恶搞。有六百万人在YouTube上观看了这段节目。有什么更能在半夜影响人们的情绪?”

苍蝇话题的影响没有持续太久。10月12日,特朗普重新开始巡回造势,在佛罗里达州斯坦福举办了一次声势浩大的集会。米勒说:“拜登的选情从此时开始进入了下行趋势。特朗普在奋起直追。他已经康复,从脸色和表现上看,他都如同获得重生一般。” 10月5日,两位候选人通过市政厅活动的隔空交锋,让拜登的声望有短暂攀升,但这种势头并未持续太久。米勒说:“两位候选人在第二次大选辩论中的表现被认为难分胜负,但特朗普上升的势头不减。”后来,特朗普在《60分钟》节目中接受莱斯利•斯塔尔采访时的糟糕表现,让他的声望严重受挫。米勒说:“女性观众认为他在羞辱一位备受尊敬的女性记者。他的表现就像是在说:‘我不在乎你,你是女人。’”拜登增加了5张选举团票,这种上升势头维持了两天。然后,特朗普止住了斯塔尔事件之后的颓势,声望又开始回升。

米勒说,在特朗普的声望恢复上升时,他就预测这种势头难以长久,而且他认为拜登的胜选概率将重新恢复到8月至9月的水平,达到80%以上,他将获得超过310张选举团票。10月28日,特朗普的胜选概率有所提升,拜登的胜选概率则下降到76.4%,选举团票为242张。到次日下午三点左右,拜登的胜选概率小幅提升到78.7%。米勒依旧认为,拜登的领先幅度将从几周前的4比1缩小到3比1。他说:“我承认民主党领先,但共和党也在努力追赶,而且这绝不是压倒性优势。特朗普绝对有胜选的可能,所有人都应该知道这一点。”(财富中文网)

翻译:刘进龙

审校:汪皓

不要低估特朗普。特朗普在搞砸了第一次辩论并感染新冠肺炎之后,他的胜选概率大降,但之后有大幅提高。这种上升的势头仍在继续,如果他的支持率继续按照这样的速度上升,美国总统大选将变得异常激烈,在选举夜之前将难分胜负。

这是西北大学(Northwestern University)数据科学家托马斯•米勒的研究结果。米勒创建了一种新方法,专门用于预测今年总统大选的结果。米勒告诉《财富》杂志:“特朗普重新开始他所擅长的造势活动之后,声望有所上升。本次大选的竞争异常激烈,双方的差距很小,但这并没有引起媒体的关注。你依旧会听到许多电视节目里大谈特谈拜登的压倒性优势,说他拿下了德克萨斯州。这是不可能的。”

米勒是西北大学数据科学项目的负责人。他曾经创建过一个类似的计算机模型,通过模拟击球手和投手之间的不同配对,预测职业棒球比赛的结果。他说该模型会模拟每一位球员的上场击球次数。“我会在正式比赛之前模拟整场比赛,看看谁能获胜,通过这种方式来确定赔率。然后我将这些赔率与博彩网站上的赔率相匹配,如果两个赔率的偏差很大,就是下注的时候。我发现在15场比赛中,可能有一两场值得下注。”

他在8月开始研究大选数据。但他并没有使用民意调查数据,或者经济状况对大选结果的影响等历史指标,尽管这是最常用的两种预测大选结果的工具。他的预测基于美国知名度最高的政治博彩网站PredictIt上发布的赔率。米勒认为,用政治赌客对候选人设定的“价格”作为指导,比受访者在接受民意调查机构的电话调查时所说的偏好更可靠。

米勒说:“投注市场提供的赔率最为可靠,因为当人们在某件事上投入真金白银的时候,你可以确信他们对这件事很有信心。如果网站上对特朗普的投注价格是40美分,拜登是60美分,而且你认为拜登胜选的概率超过0.6,你就会押注拜登。这是高效政治博彩市场的魅力所在。”米勒认为,政治期货网站能够最准确地预测“群体的智慧”。

他表示,民意调查问选民会把选票投给谁,其实是在问他们希望谁赢,“而PredictIt问的是:‘你相信谁会赢?’这个问题更一针见血。”他补充说,民意调查结果体现了几天前收集的意见,但没有体现候选人昨天的丑态,或者因为候选人在辩论中表现出色或糟糕所带来的支持率的巨大变化。他说:“我的预测结果比民意调查结果提前五天。我提前五天就知道第一次总统大选辩论的获胜者会是拜登。”民意调查结果发布的时候就已经过时。

米勒之所以信任PredictIt的赔率,是因为该网站对56个司法辖区的选举团票分别投注,包括48个“赢者通吃”的州、内布拉斯加州和缅因州的7个选区以及哥伦比亚特区。因此,他可以采用56个独立政治市场中每分钟的实时数据进行预测。他表示,PredictIt平台的流动性很高,因为该平台上有10万赌客,而且仅限于美国居民。这些人大都非常了解各县和各州本地基层的趋势导向。

他将这种方法命名为“Virtual Tout”,并在其网站上每小时更新一次预测结果。(或者通过推特账号@virtualtout发布。)米勒从PredictIt平台上提取各州市场不断变化的赔率,并把它们汇总成两个主要数据点:模型预测前副总统拜登将赢得的选举团票数,以及用百分比表示的拜登的胜选概率。米勒的网站上的一个曲线图代表了选举团票的趋势。经过米勒的方法筛选后,当PredictIt平台上各州投注窗口中的赔率更支持拜登时,曲线会上升。如果特朗普在56个地区的声望升高,就像现在一样,曲线就会下降。

图中还显示了导致选举团票数和胜选概率突然波动的重要事件。特朗普在《60分钟》(60 Minutes)节目中大发脾气或米歇尔•奥巴马在一条视频中发表了一通肺腑之言之后,这种方法在不到一个小时内显示,拜登的声望大幅提升。米勒说:“有时候我没有看新闻,但我发现时间序列出现大幅波动,然后我才会去看新闻,了解发生了什么。”

下面让我们回顾一下米勒的模型中,在第一阶段帮助拜登声望大涨的那些事件。米勒在8月初建立网站,并发现在整个8月份,围绕双方的竞选活动,拜登一直以80%至85%的胜选概率领先于特朗普(20%至15%)。到9月初,拜登依旧领先,模型预测他将获得约310张选举团票,但他要获胜还需要40张选票。从9月29日的第一次辩论开始,特朗普总统的选情变得更糟糕。米勒说:“特朗普搞砸了第一次辩论。一周后,他被确诊感染新冠病毒。我看到在消息公布之后一个小时内,拜登的选举团票数增加了四张。”这件事提醒美国人还有一场疫情正在威胁他们自身的健康和美国的经济。10月6日,特朗普神情憔悴地在沃尔特里德医院(Walter Reed)接受治疗,这时该模型预测拜登的选举团票达到326张,入主白宫的概率提高到94%。拜登似乎正在形成压倒性优势。

然后,情况发生了变化。在10月7日副总统辩论的当天,特朗普的势头开始反弹。但四天之后,《周六夜现场》(Saturday Night Live)的一段恶搞,让特朗普的上升势头戛然而止。这段喜剧节目也显示出米勒的模型对于选民情绪的快速变化极其敏感。这段节目恶搞了副总统辩论和落在彭斯头上的那只网红苍蝇,而正在与妻子吉尔观看这场辩论的拜登跳进了时间机器,变成了那只烦人的苍蝇,让人回想起电影《变蝇人》(The Fly)里变形的场面。米勒说:“从午夜左右到凌晨5点,拜登增加了多张选举团票。这肯定是因为《周六夜现场》里的恶搞。有六百万人在YouTube上观看了这段节目。有什么更能在半夜影响人们的情绪?”

苍蝇话题的影响没有持续太久。10月12日,特朗普重新开始巡回造势,在佛罗里达州斯坦福举办了一次声势浩大的集会。米勒说:“拜登的选情从此时开始进入了下行趋势。特朗普在奋起直追。他已经康复,从脸色和表现上看,他都如同获得重生一般。” 10月5日,两位候选人通过市政厅活动的隔空交锋,让拜登的声望有短暂攀升,但这种势头并未持续太久。米勒说:“两位候选人在第二次大选辩论中的表现被认为难分胜负,但特朗普上升的势头不减。”后来,特朗普在《60分钟》节目中接受莱斯利•斯塔尔采访时的糟糕表现,让他的声望严重受挫。米勒说:“女性观众认为他在羞辱一位备受尊敬的女性记者。他的表现就像是在说:‘我不在乎你,你是女人。’”拜登增加了5张选举团票,这种上升势头维持了两天。然后,特朗普止住了斯塔尔事件之后的颓势,声望又开始回升。

米勒说,在特朗普的声望恢复上升时,他就预测这种势头难以长久,而且他认为拜登的胜选概率将重新恢复到8月至9月的水平,达到80%以上,他将获得超过310张选举团票。10月28日,特朗普的胜选概率有所提升,拜登的胜选概率则下降到76.4%,选举团票为242张。到次日下午三点左右,拜登的胜选概率小幅提升到78.7%。米勒依旧认为,拜登的领先幅度将从几周前的4比1缩小到3比1。他说:“我承认民主党领先,但共和党也在努力追赶,而且这绝不是压倒性优势。特朗普绝对有胜选的可能,所有人都应该知道这一点。”(财富中文网)

翻译:刘进龙

审校:汪皓

Don't count Donald Trump out. His odds have improved substantially since bottoming after he blew the first debate and contracted COVID-19. That upward momentum is still in place, and if it continues at the same pace, the race could be too close to call by election eve.

Those are the findings of Thomas Miller, a Northwestern University data scientist who created a new methodology tailored to predicting the outcome of this presidential election. "Trump's picked up since he got back on the trail doing his thing," Miller told Fortune. "This is a very competitive race that's tightening, but the media hasn't picked up on it. You still hear lots of talk on TV about a landslide, with Biden taking Texas. That's unlikely."

Miller, director of the Northwestern data science program, created similar computer models to forecast the outcome of professional baseball games based on simulating individual matchups between batters and pitchers—every single at-bat is modeled, he says. "I play every game in its entirety before it happens, see who wins, and that's how I establish the odds. Then I match those odds with those on the betting sites, and if there’s a major divergence, that's the time to bet. I found that out of 15 games, maybe one or two are worth betting on."

In August he started crunching data on the election. But instead of using the two most common tools—weighing the polling numbers or using such historical measures as how the economy is likely to shape the outcome—he based his predictions on the odds posted on America's most prominent political gaming site, PredictIt. For Miller, the "prices" that political gamblers place on the candidates are a far more reliable guide than the preferences that respondents state in pollsters’ telephone surveys.

"These betting markets provide the best odds because when people put their own money into something, you can be sure that's what they believe," says Miller. "When Trump's posted price is 40 cents and Biden's is 60 cents, and you think Biden's chances are better than 0.6, you'll bet on Biden. That's the beauty of an efficient political marketplace." For Miller, the political futures sites best project "the wisdom of the crowd."

Miller notes that the surveys ask people whom they'll vote for, meaning whom they'd like to win: “PredictIt effectively asks, ‘Whom do you believe will win?’ That's the better question." He adds that polling results reflect opinions collected days before, and not the gaffe the candidate committed yesterday, or the big shift in support in the hours after a good or bad debate. "My results are out five days before the polls come out," he adds. "I was five days in advance knowing the first presidential debate was won by Biden." By the time they appear, polling results are already out of date.

Miller relies on PredictIt because the site takes bets on 56 separate jurisdictions awarded electoral votes: the 48 "winner-take-all" states, and seven districts in Nebraska and Maine, as well as the District of Columbia. Hence, he's able to deploy real-time, minute-by-minute data from what are effectively 56 separate political markets. He notes that the PredictIt platform is highly liquid, since it boasts 100,000 bettors, and that it's restricted to U.S. residents, many of whom are knowledgeable about the on-the-ground, bellwether trends in their counties and states.

The methodology, trademarked the Virtual Tout, updates the forecasts every hour on his website. (Or at Twitter at @virtualtout.) Miller distills the shifting odds in PredictIt’s mainly state-by-state markets into two principal data points: first, the number of electoral votes that the model forecasts Biden will win, and second, the former vice president's chance of victory, shown as a percentage. Miller’s site shows a curve representing the trend in electoral votes. The curve rises when the PredictIt odds from the state betting windows, filtered through Miller's methodology, move in Biden's favor. The trajectory descends, as now, when Trump's fortunes across the 56 markets improve.

Superimposed on the graph are important events, many of which cause an immediate spike or cratering in the candidates' electoral count and odds of winning. In less than an hour, the methodology registers Biden's bump from Trump's angry outburst on 60 Minutes or Michelle Obama's heartfelt video message. "Sometimes I haven't been listening to the news, and I see the time series move dramatically, then I turn on the news to see what made it happen," says Miller.

Let's trace the events that in the first phase measured by Miller brought a big uptick in Biden's fortunes. Miller launched the site in early August and found that Biden held an edge of 80% to 85% to Trump's 20% to 15% during the entire month that encompassed both campaigns. By early September, Biden was holding that lead, and the model gave him around 310 electoral votes, 40 more than needed for victory. Starting with the first debate on Sept. 29, things got even worse for the President. "He blew the first debate," says Miller. "A week later, he's diagnosed with COVID-19. I could see Biden's count jump by four votes within an hour of the announcement." That reminded Americans of the plague threatening their health and the economy. On Oct. 6, as Trump languished in Walter Reed hospital, Biden's numbers hit their high-water mark of 326 electoral votes and a 94% probability of taking the White House. A Biden landslide appeared to be building.

Then, the momentum shifted. The start of Trump's comeback coincided with the vice presidential debate on Oct. 7. But in a comical episode that also shows the sensitivity of Miller's model to passing changes in voters' mood, Trump suffered a blip following the Saturday Night Live skit four days later. The SNL parody of the VP debate showed the famous fly sticking to Pence's head, and Biden, who had been watching the face-off with wife Jill, jumping into a time machine to be transformed into the offending insect, recalling the metamorphosis in the movie The Fly. "From around midnight to 5 a.m., Biden gained a few votes," says Miller. "It must have been the SNL skit. Six million people viewed it on YouTube. What else would move the needle in the middle of the night?"

The fly didn't sting for long. On Oct. 12, Trump returned to barnstorming, hosting a signature raucous rally in Stanford, Fla. "The downward slope for Biden began," says Miller. "Trump's back on the trail. He's recovered and acts, and looks, reborn." The dueling town halls on Oct. 5 gave Biden a brief lift that quickly faded. "The second debate was regarded as a draw, but Trump's momentum continued," says Miller. Then Trump suffered what looked like a serious setback from his obstreperous performance in his 60 Minutes interview with Lesley Stahl. "Women viewers perceived that he was insulting a respected female journalist," says Miller. "It's as if he was saying, 'I don't care about you, you're a woman.'" Biden gained around five electoral votes and benefited for two days. Then Trump's gains got right back on the track they'd jumped after the Stahl debacle.

Miller says that when the Trump resurgence started, he expected it to be short-lived and thought that Biden would resume the 80%-plus odds and over 310 electoral votes he'd enjoyed from August through September. On Oct. 28, Trump's chances improved as Biden’s slipped to 76.4% and 242 electoral votes. By mid-afternoon the next day, Biden had gained a bit to 78.7%. Miller still puts Biden's odds of victory at 3-to-1, down from 4-to-1 a few weeks ago. "I would say the Democrats have the lead, but the Republican ticket is catching up, and this is by no means a landslide," he says. "Trump can absolutely win, and everyone should be aware of that."

热读文章
热门视频
扫描二维码下载财富APP