Aggregate User Activity, Fit Regression, Interpret Coefficients
Company: Airbnb
Role: Data Scientist
Category: Data Manipulation (SQL/Python)
Difficulty: Medium
Interview Round: Technical Screen
user_metrics
+----------+------------+---------+--------+-----------+
| user_id | activity_dt| variant | clicks | purchases |
+----------+------------+---------+--------+-----------+
| 101 | 2023-05-01 | A | 12 | 1 |
| 102 | 2023-05-01 | B | 4 | 0 |
| 103 | 2023-05-02 | A | 6 | 1 |
| 104 | 2023-05-02 | B | 9 | 2 |
| 105 | 2023-05-03 | A | 3 | 0 |
+----------+------------+---------+--------+-----------+
##### Scenario
Given relational event data, you must write SQL and Python to build a modeling dataset and run a regression.
##### Question
Write SQL to aggregate daily user activity into features.
2) In Python, fit a linear (or logistic) regression and interpret coefficients.
##### Hints
Use window functions for rolling metrics; in Python rely on pandas and statsmodels or sklearn.
Quick Answer: This question evaluates skills in relational data aggregation and feature engineering using SQL alongside fitting and interpreting regression models in Python, targeting competencies in transforming event-level user metrics into a modeling dataset and interpreting coefficient estimates.