jindřich mynarz and václav zeman | db-quiz: a dbpedia-backed knowledge game

DB-quiza DBpedia-backed knowledge gameJindrich Mynarz, Václav Zeman— University of Economics, Prague

SEMANTiCS 2016, September 12–15, 2016, Leipzig, Germany

Game mechanics

→ Play at http://mynarz.net/db-quiz

DB-quiz is a knowledge-based game inspired by the Czech TV show AZ-kvíz.

Win board fields by guessing entity’s name based on its abbreviation and description. The player who connects all sides of the triangular game board wins.

Game mechanics

Data

Game questions are automatically generated from Czech or English DBpedia.

Domains of questions are partitioned by rdf:type (such as persons or films) or by dcterms:subject (such as members of the Communist party).

Alternatively, questions can be sourced from a Google Spreadsheet.

Implementation

A single-page application developed in Clojurescript backed by a SPARQL endpoint with pre-processed data from DBpedia.

Currently, it lacks a multiplayer mode, so that players need to take turns playing in the same browser.

Source code at https://github.com/jindrichmynarz/db-quiz.

Live demo at http://mynarz.net/ db-quiz.

Problems addressed

1.

How to estimate difficulty of questions automatically?

2.

How to clean questions from spoilers that give away the answers?

Estimating difficulty of questions

We used indegree (= number of inbound links via dbo:wikiPageWikiLink to the question’s answer) as a proxy to difficulty.

We split the area under the curve of indegree distribution in a question’s domain into thirds that correspond to 3 game difficulties: easy, normal, and hard.

Removing spoilers from questions

We use the answer’s surface forms from anchor texts of inbound links (dbo:wikiPageWikiLinkText) or name-like properties (such as dcterms:title or dbo:birthName).

This way we obtain variant spellings, declinations, or aliases of the answer.

Each surface form found in the question is replaced by the answer’s abbreviation.

Evaluation

We tested the game via online user testing.

6 months worth of Google Analytics data (1401 visits from 892 users, 3514 answers for 2315 questions, 242 spoiler reports, and 138 finished game sessions).

Tracked events:

● Answer correctness: + derived answer success rate● Spoiler reports: A/B testing with/without spoilers

removed

Evaluation results

Spoilers reported approximately 4.5× more for questions without spoilers removed.

Aggregated answer

success rates:

We tested the correlation of the averaged answer success rates with indegrees and the numbers of page views.

Evaluation results

Indegree has a weak to moderate positive correlation with answer success rate. However, number of page views has a stronger correlation.

Future work

● Use page views for estimating difficulty.

● Add yes/no questions for the missed fields.

● Implement a multiplayer mode.

→ Play at http://mynarz.net/db-quiz