2. Who am I?
• Data Scientist@Uber
• Previously, led Data Science@startup in India
• Worked at Facebook, BofA
• UCB, IIT Bombay (India)
• Half Marathon Runner
• Husband
3. Why to enter into Data
Analytics/Science?
2.5 *1018 Bytes of data generated everyday (--IBM)
150,000 Shortage of Data Scientists in US alone in
2018 ( -- Mckinsey and Co.)
5. What are Employer’s Requirements
What are Employer’s Requirements?
• Technical Skills
• Knowledge of Statistics
• Structured Thinking
• Business Understanding
• Communication Skills
• Attention to details
7. Technical Interviews
• SQL : Joins, GroupBy , Where, Having, Window Functions, Query optimizations,
NoSQL
• R/Excel : Level depends on the job
• Tableau or other BI tool: Useful if you are going for reporting/dashboarding
kind of role
8. Guesstimates (Type 1 Case Interviews)
• These are the kinds of interviews where you are required to estimate a number
by putting a framework to the problem, making assumptions and coming up
with a final number.
• For e.g. “ Estimate the number of balls/ liquor bottles in USA”
• Few pointers:
• It is the approach that matters – not the final numbers
• Call out all the assumptions and possible blind spots
• Clearly state the framework and segmentations you make
9. Real Life Case Study
A case interview starts with a broad business question and narrows down in a particular
direction. It generally starts with a very simple problem and then interviewers tend to increase
the complexity as you solve the problems.
Few pointers:
• Case study is all about three things : Structure, Structure, Structure. Focus on putting a frame
work to the problem.
• Again call out all the assumptions.
• Think out loud, interviewer is looking for your thought process
• Communicate effectively
10. Some more things
1. Update your Linkedin profile
2. Attend local meetups
3. Keep yourself updated through:
1. News sites like www.datatau.com (hacker news for data
science/analytics)
2. Follow data science/analytics leaders on Twitter ( for e.g DJ Patil,
Andrew Ng etc. )
12. Yammer ($1.2Bn Acquisition by Microsoft)
Yammer is a social network for communicating
with coworkers. Individuals share documents,
updates, and ideas by posting them in
groups.Think of it like Facebook for Work.
Yammer has web,mobile and tablet apps.
19. Further Exploration
It seems the issue is with the mobile app related to long-time user
retention. Possible issues can be:
1. Mobile app has become too heavy with new features and it
crashes
2. Re-engagement Emails that were sent for retaining users are not
been viewed on mobile clearly
3. A bug in recording data in mobile
4. Etc …
So it’s likely that there’s a problem with the mobile app related to long-time user retention. At this point, you’re in a good position to ask around and see if anything changed recently with the mobile app to try to figure out the problem. You might also think about what causes people to engage with the product.
1. One of the easiest things to check is growth, both because it’s easy to measure and because most companies (Yammer included) track this closely already. In this case, you have to make it yourself, though. You’ll notice that nothing has really changed about the growth rate—it continues to be high during the week, low on weekends:
Since growth is normal, it’s possible that the dip in engagement is coming from existing users as opposed to new ones. One of the most effective ways to look at this is to cohort users based on when they signed up for the product. This chart shows a decrease in engagement among users who signed up more than 10 weeks prior:
The understanding that the problem is localized to older users leads us to believe that the problem probably isn’t related to a one-time spike from marketing traffic or something that is affecting new traffic to the site like being blocked or changing rank on search engines. Now let’s take a look at various device types to see if the problem is localized to any particular product:
So it’s likely that there’s a problem with the mobile app related to long-time user retention. At this point, you’re in a good position to ask around and see if anything changed recently with the mobile app to try to figure out the problem. You might also think about what causes people to engage with the product.