Sentence retrieval is an important step in many question-answering (QA) technologies. However, characteristics of sentences and of the question-answering task itself often make it difficult to apply document retrieval techniques to sentence retrieval. The use of translation dictionaries offers one potentially useful approach to sentence retrieval, but training such dictionaries using QA corpora...

The theme of the the KDD cup 2011 challenge was to identify user tastes in music by leveraging the actual Yahoo! Music dataset. Two datasets were sampled for the raw data: The larger dataset contained 262,810,175 ratings of 624,961 music items by 1,000,990 users was created for Track1 and and a smaller dataset with 62,551,438 ratings of 296,111 music items by 249,012 was created for Track2. A d...

Spell-checking is the process of detecting and sometimes providing suggestions for incorrectly spelled words in a text. Basically, the larger the dictionary of a spell-checker is, the higher is the error detection rate; otherwise, misspellings would pass undetected. Unfortunately, traditional dictionaries suffer from out-of-vocabulary and data sparseness problems as they do not encompass large ...

Many auction settings implicitly or explicitly require that bidders are treated equally exante. This may be because discrimination is philosophically or legally impermissible, or because it is practically difficult to implement or impossible to enforce. We study so-called anonymous auctions to understand the revenue tradeoffs and to develop simple anonymous auctions that are approximately optim...

This paper investigates the composition of search engine results pages. We define what elements the most popular web search engines use on their results pages (e.g., organic results, advertisements, shortcuts) and to which degree they are used for popular vs. rare queries. Therefore, we send 500 queries of both types to the major search engines Google, Yahoo, Live.com and Ask. We count how ofte...

The goal of our research was to be able to accurately predict the outcome of every matchup in a March Madness bracket. This is an extraordinarily difficult problem because of the high amount of variance in college basketball and the sheer number of games that are played in the tournament. In the history of March Madness, no one has ever created a perfect bracket. Last year, Warren Buffett agree...

We analyze an environment in which bidders’ private values change over time due to both private investments and exogenous shocks. We demonstrate that a highlydecentralized mechanism achieves efficiency. The mechanism requires a stage of costly public announcements (i.e., signaling) to induce efficient investment. For this reason, an equilibrium selection issue arises, but can be handled by a mi...