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AI & Data Scientist

Learn the working loop of a data scientist: turn a fuzzy request into a metric, measure uncertainty, run fair experiments, estimate effects you cannot randomise, evaluate models honestly and explain what you found. Every lesson follows Pantry, one grocery-delivery app, from its first question to its final report.

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Course curriculum

Mathematics for Framing Questions4 lessons

Start where every analysis starts: the decision. Turn requests into metrics with clear numerators and denominators, report change in points and percents without confusion, weigh options by expected value, and use logarithms for skewed data and growth.

  1. From Decision to Metric12 min
  2. Absolute and Relative Change12 min
  3. Expected Value for Decisions14 min
  4. Logarithms for Skew and Growth12 min
Statistical Inference4 lessons

Every number from a sample wobbles. Measure the wobble with a standard error, turn it into a confidence interval, test whether a difference could be luck, and size a study so it can actually find the effect you care about.

  1. Samples and Standard Error14 min
  2. Confidence Intervals14 min
  3. Hypothesis Tests and p-values15 min
  4. Errors, Power and Sample Size15 min
Experiments and Causal Effects5 lessons

Separate cause from coincidence. Spot confounders, design and read an A/B test, and when you cannot randomise, estimate effects with regression and difference-in-differences.

  1. Correlation, Confounding and Causation12 min
  2. Designing an A/B Test14 min
  3. Reading an A/B Test Result15 min
  4. Regression: Holding Other Things Fixed15 min
  5. Difference-in-Differences14 min
Exploring and Explaining Data5 lessons

Check what one row means, ask why values are missing, catch Simpson's paradox before it catches you, draw charts that make one point, and write up a result so a busy reader can act on it.

  1. Know the Grain of Your Data12 min
  2. Missing Values Have Reasons14 min
  3. Simpson's Paradox: Segment Before You Conclude14 min
  4. One Chart, One Message12 min
  5. Communicating Results15 min
Evaluating Models5 lessons

Split data the way the model will be used, beat a simple baseline, read precision and recall from a confusion matrix, choose a threshold from real costs, and hunt down leakage before it fools you.

  1. Train, Validation and Test Sets13 min
  2. Beat a Baseline First13 min
  3. Precision and Recall15 min
  4. Choosing a Threshold15 min
  5. Data Leakage15 min