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The Impact of Technical Domain Expertise
on Search Behavior and Task Outcome
Julia Kiseleva, Alejandro Montes García,
Jaap Kamps, Nikita Spirin
Eindhoven University of Technology
University of Amsterdam
University of Illinois at Urbana-Champaign
WSDM Workshops ’16, San Francisco, USA
Developer
Motivation: Domain vs. Search
Expertise
Not
Developer
Developer
Motivation: Domain vs. Search
Expertise
Not
Developer
Search
Expertise
Search
Expertise
Developer
Motivation: Domain vs. Search
Expertise
Not
Developer
Search
Expertise
Search
Expertise
Technical
Expertise
Technical
Expertise
Java
Developer
Motivation: Domain vs. Search
Expertise
Not Java
Developer
Java
Expertise
Java
Expertise
Java
Developer
Motivation: Domain vs. Search
Expertise
Not Java
Developer
Java
Expertise
Java
Expertise
Expert Clicks are less
Biased
• Main: How does technical domain expertise
influence search behavior?
1. What is the impact of technical domain
expertise on the search process?
2. What is the impact of technical domain
expertise on search outcome?
Research Objectives
• Online Setup
• Technical Expertise: Java and JavaScript
• Collected Data:
oDemographic data: age, gender education level;
oSelf reported expertise in Java and JavaScript
oTest to measure expertise in Java and JavaScript
User Study Design
• 29 participants
• Education: High school 8%, Bachelor 12%, Master
56%, PhD 24%
• Age: 18-23 years 16%, 24-29 years 36%, 30-35 years
28%, 36-42, years 16%, 43-48 years 4%
User Study Data
Position Bias vs Technical Expertise
Right Answer vs Technical Expertise
• The technical domain expert's biases was less
pronounced and they tended to check the SERP's bottom
• Having a general programming expertise helped to derive
the good answers on the SERP, but the experts with high
proficiency managed to detect better answers as they dug
them from the bottom of the SERP
Conclusions

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The Impact of Technical Domain Expertise on Search Behavior and Task Outcome

  • 1. The Impact of Technical Domain Expertise on Search Behavior and Task Outcome Julia Kiseleva, Alejandro Montes García, Jaap Kamps, Nikita Spirin Eindhoven University of Technology University of Amsterdam University of Illinois at Urbana-Champaign WSDM Workshops ’16, San Francisco, USA
  • 2. Developer Motivation: Domain vs. Search Expertise Not Developer
  • 3. Developer Motivation: Domain vs. Search Expertise Not Developer Search Expertise Search Expertise
  • 4. Developer Motivation: Domain vs. Search Expertise Not Developer Search Expertise Search Expertise Technical Expertise Technical Expertise
  • 5. Java Developer Motivation: Domain vs. Search Expertise Not Java Developer Java Expertise Java Expertise
  • 6. Java Developer Motivation: Domain vs. Search Expertise Not Java Developer Java Expertise Java Expertise Expert Clicks are less Biased
  • 7. • Main: How does technical domain expertise influence search behavior? 1. What is the impact of technical domain expertise on the search process? 2. What is the impact of technical domain expertise on search outcome? Research Objectives
  • 8. • Online Setup • Technical Expertise: Java and JavaScript • Collected Data: oDemographic data: age, gender education level; oSelf reported expertise in Java and JavaScript oTest to measure expertise in Java and JavaScript User Study Design
  • 9.
  • 10. • 29 participants • Education: High school 8%, Bachelor 12%, Master 56%, PhD 24% • Age: 18-23 years 16%, 24-29 years 36%, 30-35 years 28%, 36-42, years 16%, 43-48 years 4% User Study Data
  • 11. Position Bias vs Technical Expertise
  • 12. Right Answer vs Technical Expertise
  • 13. • The technical domain expert's biases was less pronounced and they tended to check the SERP's bottom • Having a general programming expertise helped to derive the good answers on the SERP, but the experts with high proficiency managed to detect better answers as they dug them from the bottom of the SERP Conclusions

Hinweis der Redaktion

  1. Users exhibit remarkably different search behavior, due to various differences that can greatly influence their ability to carry out successful searches. Previous work mostly consider how different is search experise among users and how it does influence their search success. We consider how expertise in particular domain influence user success. Let’s consider example we have two user and based on their previous interaction we know that one is developer and second one is not.
  2. Based on previous interaction and applying available methods we can infer that they are have similar search expertise. They are both have excellent search skills.
  3. What about their expertise in programming domain? No this expertise is not equal – user on the left is professional Java developer and has overall good programming skills. The user on the right is a profession cheaf and does not have a clue about programming. These two users have completely different profile. The probability the left user would search for some information about programming is very high. The probability that right user would look for programming queries is very low. And if she would? Would your clicks be useful for relevance feedback paradigm?
  4. Let’s consider more realistic scenario that can happen. We have two users: Java and JavaScript developer. They both have a solid background in programming. Right user wants or needs to study a new programming language. – Java. In the same time left users still is looking search queries for Java language. For example to refind some information. Our hypothesis is that expert users are more efficient in finding RIGHT correct answers and non-expert most likely trust position of the ranking. Therefore non-expert clicks on first results – which guarantee most relevant answer but nobody guarantees you correct information. Moreover, usually amount of users and amount of queries are mostly coming from novice users – because they are in explorative phase.
  5. They provide more feedback to Search engine. But are clicks from non-experts having the same weight/importance for the search eqngine feedback?
  6. THEREFOR our reseach objectives are the following.: from slides … We did fist explorative study to answer our research questions.
  7. We design the “realistic” setup where we tackle users with general programming expertise. Because we believe it’s not realistic to compare restaurant cheefs vs developers. We select two topic – Java and JavaScript which are totally different programming language. To make study more realistic – we made it online – so users were at their enviroment. We collect the following data: ON THE SLIDE
  8. The study consists of two sets of ten tasks or questions that related to the programming language. Our tasks were modeled after those that users post in specialized Q&A sites. For example, one of the tasks for Java was: Can you override a static method in Java?” Interestingly, five attenders have changed their mind. For example, we have got the following comment: `Turns out there are some concepts which have `faded' a bit in my memory!', which basically shows that even good developers sometimes need to refresh their memory. We provide a search query for each question that is used to retrieve a SERP with ten results from the Bing API.1 The given SERP is randomly re-ranked in order to estimate the position bias. The participants are asked to find the answer and to submit this URL. In addition, we ask participants (1) to tell us whether the query is formed in a right way or not; (2) to indicate if they knew the answer upfront. We collected ground truth answers from an expert who judged all shown results. After finishing the study, users are asked to report again their proficiency in programming, Java and JavaScript to see if they changed their self-consideration after the test.
  9. The user study data. Histogram of test scores (based on test) to represent the balance of Java and JavaScript expertise in our use sample.
  10. We can clearly see that the whole population is biased to the position of the result on the SERP, showcasing that results are scanned from top to bottom. We see an even stronger position bias for those with lower test scores, while for those with a higher test score, the position bias is less pronounced. The technical experts more frequently pick a lower ranked results { although even the experts clearly prefer top ranked results. The position bias as shown in Figure 5 does not show a monotonically declining pattern, as some positions such as 6 and 9 are more popular than others. Closer inspection re- veals that this is due to the popularity particular Q&A sites, in particular http://stackover ow.com/, that attract atten- tion. As we are working with a single randomized SERP for each question|allowing us to compare position across participants|the distribution of popular Q&A sites is not exactly uniform over the sample. So in addition to the po- sition bias, we see a domain bias.
  11. Figure 6 shows the distribution of correct answers over ex- pertise levels for Java (left) and for JavaScript (right). We see a clear relation for both Java and Java script: higher expertise levels lead to higher fractions of correct answers. The relation is highly signicant (Pearson 2, p < 0:0001) for both Java and JavaScript. There is an interesting devia- tion for those scoring very low on Java, yet producing many correct answers. A plausible explanation it that these partic- ipants have sucient passive understanding, hence can rec- ognize answers pages on the information on the web pages, but cannot actively produce this in the test. This is sup- ported by their relatively high fractions of \I don't know" answers on the Java expertise test.