利用移动应用软件进行众包给心理学研究带来“大数据”

根据美国心理学协会出版的一篇文章，有这样一款节奏快速的游戏应用软件以创纪录的速度为研究人员提供了数十亿项数据，游戏中玩家扮演机场安检人员操作X光扫描仪筛查旅客的行李箱包。

这是一份发表于美国心理学会期刊《实验心理学：人类知觉与绩效》Experimental Psychology: Human Perception and Performance的报告，其主要合著者杜克大学博士史提芬R.米特罗夫Stephen R. Mitroff说：“利用真实地考验认知能力或其他大脑功能的游戏应用软件，众多的移动装置（智能手机和平板电脑等）为研究人员提供了一个令人兴奋的崭新的众包一项实验的方法。过去在实验室里耗费数十年进行研究的问题，或者说根本无法在实验室里找到现实答案的问题，现在可利用在较短时间内收集的大数据得以考察。

研究人员与这款广受大众喜爱的游戏《机场安检扫描仪》Airport Scanner的开发商Kedlin Co.协作以展示移动科技收集数据的潜力，游戏考验玩家发现并指出正在通过X光扫描仪的行李里面的违禁品的能力。玩家逐件地审视箱包，点按触摸屏指出违禁品。游戏开始时玩家日志上列举了一些常见的违禁品（如枪支，手榴弹，弹簧刀等）和非违禁品（如耳机，衣服等），随着游戏的进行，这个列表会从寥寥几项扩张到数百项。

这份报告中提到，2013年1月至2014年11月期间，这款游戏提供了从超过7百万智能手机或平板电脑的超过20亿次的考验所产生的匿名数据，一直以来米特罗夫和他在“杜克认知神经科学中心”的研究团队正在对这些数据进行分析。玩家们在这款游戏安装到智能手机或平板电脑时同意提交相关数据。

游戏中有一个研究项目是考察玩家们发现罕见物品（在少于0.1%的行李中出现）的能力。

米特罗夫说：“像这样的罕见物品出现在屏幕上，意味着你在1000次考验中才能碰到1次。在实验室环境里，需要太多次考验才能统计出如此接近现实的概率（这样的工作量对于研究人员来说过于繁重）。在大型数据集中，我们能在数百件个案中找到大约30个最罕见的目标”

通过另一个实验还发现，当两件违禁品出现在同一件箱包里时，玩家们容易漏掉1件，而两件不同违禁品出现在同一件箱包里漏掉其中1件这种情况发生的可能性大于两件相同违禁品的情况。举例来说，相对于发现一个炸弹却漏掉另一个炸弹的个案，更多的情况是玩家们发现了一罐汽油却漏掉了一个炸弹。

米特罗夫说：“尽管利用游戏界面来评估认知能力对于心理学研究领域已算不上什么创新，奇迹般的移动互联技术为大规模地研究认知过程提供了可行性。早在1998年，哈佛大学医学院博士杰瑞米M.沃尔菲Jeremy M. Wolfe就分析了1百万次考验，以研究视觉搜寻。这样庞大得足以震撼人心的数据量是历时10年收集取得的。而今天我们却能够通过《机场安检扫描仪》仅仅用1天的时间就收集到超过1百万次考验的数据。”

根据这份报告，众包的优势还包括，它是一种成本低廉的自动地连续地收集数据的方法，它还能模拟现实中的复杂情况，而这些复杂情况是在实验室里难以应对的。

然而，报告的合著者们指出，为取得用于研究的数据而采取的众包方式确实存在短板。研究人员必须具备开发充满乐趣的游戏应用软件的技能，否则就需要与游戏开发商合作。收集来的大量数据未必就是高质量的，优质数据的获得有赖于精心设计的贯穿于整个游戏的留给玩家们作答的问题。以众包方式采集数据意味着研究人员无法选择玩家。

英语原文：

Crowdsourcing with mobile apps brings ‘big data’ to psychological research

Aast-paced game app where players pretend they are baggage screening officers operating airport x-ray scanners has provided researchers with billions of pieces of data in record time, according to an article published by the American Psychological Association.

“Mobile devices offer researchers an exciting new means to crowdsource an experiment using games that are actually tests of cognition or other brain functions,” said Stephen R. Mitroff, PhD, of Duke University, lead author of the report, published in APA’s Journal of Experimental Psychology: Human Perception and Performance. “Questions that could have taken decades to answer in a laboratory setting, or that could not be realistically answered in a lab, can be examined using big data gathered in a relatively short time.”

To demonstrate the potential of mobile technology to gather data, the researchers partnered with Kedlin Co., the developer of the popular mobile app game Airport Scanner, which challenges players to identify illegal items in luggage passing through an airport x-ray scanner. Players view one bag at a time and tap their touchscreen to identify banned items. The game includes a logbook of illegal items (e.g., guns, hand grenades, switchblades) and legal items (e.g., ear phones, clothing), and the list expands from a handful of possible target items to hundreds as players progress through the game.

Between January 2013 and November 2014, the game provided anonymous data from more than 2 billion trials from over 7 million mobile devices that Mitroff and his research team at the Duke Center for Cognitive Neuroscience have been analyzing, the report said. Players consent to the data collection when installing the game on their smartphone or other hand-held device.

One research question explored through the Airport Scanner game was examining players’ ability to spot items that occurred on screen very rarely, or in less than 0.1 percent of all bags.

“When a target appears only 0.1 percent of the time, you need 1,000 trials to get just a single case of that target. Too many trials would be needed to realistically assess detection of that particular target in a laboratory setting,” Mitroff said. “With the large dataset, we were able to look at hundreds of cases for each of the nearly 30 rarest targets.”

Another experiment found that when two banned items both appeared in a bag, players were more likely to miss the second to-be-found item when the two were different than if they were identical. For example, players were more likely to miss a dynamite stick after finding a gasoline can than they were to miss a dynamite stick after first finding a dynamite stick.

“While using a game interface to assess cognitive abilities is not new to psychological research, mobile technology offers a phenomenal opportunity to examine cognitive processes on a large scale,” Mitroff said. “In 1998, 1 million trials were analyzed by Jeremy M. Wolfe, PhD, of Harvard Medical School, to understand visual search. This was a mind-blowing amount of data that took 10 years to collect. Today, we can collect over a million trials a day through Airport Scanner.”

Other advantages of crowdsourcing include that it can be a less-expensive means of collecting data automatically and continuously and that it has the ability to mimic real-world situations that are difficult to address in a laboratory, according to the report.

Crowdsourcing research data does have disadvantages, the authors noted. Researchers must have the skills to create a fun game app or they need to partner with a developer. Collecting large amounts of data may not necessarily result in high-quality data, which requires carefully developing research questions to be addressed through the game. And collecting data through crowdsourcing means researchers have no control over who is playing, they said.