oDCM - Course Summary & Exam Preparation

If you haven't done so, please explore the exam page & example questions at https://odcm.hannesdatta.com/docs/exam.

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• Course summary
• From here onwards
  • Recognizing limitations
  • Seizing research opportunities
• Course evaluation
• Exam preparation
• Remaining questions

• Research is by far more impactful than non-webdata-based research
  • Explore novel phenomena, be timely!
  • Boost ecological value, get closer to what managers use and are interested in!
  • Facilitate methodological advancement (e.g., text, images, video)
  • Better measurement (e.g., control variables)
• But: challenging!
  • Programming skills to master technical challenges
  • Conceptual thinking to navigate design choices & legal risks

• Important of “broadening horizon” (e.g., assume perspective of various stakeholders, exceed geographical boundaries, use aggregators rather than primary data providers)
• Consider alternatives to scraping (i.e., avoid defaulting! e.g., APIs, but also ready-made data sets)
• Scope the data context (i.e., understand how the data is generated, assess reliability of the data, explore user conversations about the data, etc.)

• Look out for information - especially the “surprising ones!”
• Look out for variables (e.g., to compare to other studies), but also to see time availability differences
• Spend time mapping your navigation path
• Real-time data collection required?! (e.g., wrong historical data, inaccurate timestamps?)
• Algorithmic biases present? Can exert control?

• How long does the data collection run?
• How to sample/seed?
• To which population do the seeds generalize?
• At what frequency to extract the data (e.g., once? multiple times?)
• How to process the data on-the-fly? (e.g., first store as JSON, then parse; pandas-based parsing)

• Scientific purpose, and run by research institution?
• Scale and scope? (all data vs. small sample? running time)
• Location of data provider and users
• “Go” decision from provider? Technical intrusiveness?
• Data management & use, commercialization

• Prototyping is extremely important
  • requests + beautifulSoup vs. selenium (Chromedriver)
  • extraction methodology (e.g., tags, classes or other attributes, capturing .get_text() vs. the values of attributes) + stability
  • array misalignment (obey the hierarchy of stuff/how it is structured!!!)
  • scheduling, hiding passwords
  • revise navigation paths
  • add comments to code (make it understandable for others, e.g., using ChatGPT)
• Start documentation from a readme template
  • Generate plots, descriptive stats
  • Think as a “data supplier” rather than narrowly focusing on one (research) question

• Based on Guyt et al. 2024
• Research opportunities
• Hands-on-framework: Extraction, Looping, Timing, Infrastructure
• Challenges & Opportunities for Retail Scraping
  • Overcoming matching challenges and time alignment
  • LLMs for web scraping

• Web data entails modeling challenges - not covered in this course (e.g., self-selection, endogeneity, “messy” data)
• Web data can't give you all (i.e., it looks l ike internal clickstream data, but it is not)
• Legal and ethical issues not fully explored

• Collecting data for Master thesis

  • tell my colleagues you have the skills
  • start now, use later (data collection can take a long time!)

• PhD and research master students can “invest” into data collections

  • data was crucial to what I study
  • maybe you are a future researcher/PhD student? Start today!

1. Scout out emerging phenomena
2. Study phenomena that can't be captured otherwise (i.e., unobtrusively)
3. Study diverse populations (e.g., moving being WEIRD, more socio-economic backgrounds + geographies)
4. Generating realistic stimuli for experiments (e.g., brand logos)

1. Unleashing real-time data collections (cf. historical)
2. Conduct & support field experiments with a platform's user base
3. Use APIs to access algorithms, rather than data (e.g., Google Cloud Vision, OpenAI)
4. Build own research APIs
5. Use aggregators & archive.org

• Please hand in so we can make the data package public!

  • Take out any passwords (store as environment variables instead)
  • Remove any unnecessary files
  • Want to keep your names on the documentation or anonymize them? Choose.
  • Don't make statements that are too bold!

• Re-read the grading rubric on the course site!

• You will receive invite to self- and peer assessment via email

• Organization
  • When: 1 April (time? check Osiris/registration)
  • Work max. 3 hours on exam
• How?
  • access to TestVision
  • access to Jupyter Notebook
  • I make selected resources available on the instruction page; want to submit your own cheatsheet? Do so seven days before the exam (see link on Canvas)

• You have access to a “Demo exam” on TestVision.
• Let's walk through it!

• let's look at some questions now
• prep well! Expect new websites (for scraping), new endpoints of APIs (of sites that you know), selenium
• Internet is available; but: no use of sites/tools (e.g., ChatGPT), or our course Chatbot.

• Practice scraping an unknown website
  • e.g., tutorials at tilburgsciencehub.com,
  • working with music-to-scrape.org, tilburg.ai
  • focus on “category overview pages” & array misalignment – the scraper will account for a large share of your grade
• You will be asked to use selenium for some subquestions; BeautifulSoup will be the base
• Cover “Fields of Gold” (2022), including the web appendix, sample size calculations and legal concerns (+ reason through challenges) + Guyt et al. 2024 (J. of Retailing)

• Course evaluation has been immensely important to this course
  • This edition: updated tutorials, refined feedback on coaching support
  • Last edition: TA support for coaching, new computer setup session, computer lab sessions, developed Journal of Retailing (2024) paper with hands-on guide to scraping, moved exam to campus, built music-to-scrape.org
• Course evaluation has been critical to my career
  • Without my past evaluations, I wouldn't be teaching to you today
  • I will look at all comments
  • Scores are most important to show importance of this course
• You will be invited via Evalytics

• how to ease onboarding?
• how to make sure all software (including Chromedriver is installed)?
• Feel you've got enough support?

• Stay in touch
  • LinkedIn,YouTube, Twitter
  • WhatsApp! +31 13 466 8938
• Contribute to Tilburg's Open Science initiatives!
  • https://tilburgsciencehub.com as content developer / community manager
  • change this course at https://github.com/hannesdatta/course-odcm
    
    
• And, finally… let's show to the world how awesome your new skills are!