Harvard STAT 111: Introduction to Statistical Inference
Stat 111 is the sequel to Stat 110, turning probability into inference: estimators, maximum likelihood, confidence intervals, hypothesis testing, and Bayesian inference, taught with the same story-driven style. It's the second core course for statistics concentrators and a favorite of quant-leaning economics and CS students.
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Build my STAT 111 study planWhat makes it hard
Inference inverts the mental direction of Stat 110 — from model to data becomes from data back to model — and students fluent in probability still wobble at the conceptual layer: what a confidence interval does and doesn't say, what the likelihood actually is. The problems demand the same creative setup instincts as 110, now with statistical judgment stacked on top.
What you'll cover
- • Estimators and their properties
- • Maximum likelihood estimation
- • Confidence intervals
- • Hypothesis testing and p-values
- • Bayesian inference
- • Regression and prediction
The STAT 111 study guide
How to study for Harvard STAT 111, step by step.
- 1
Re-sharpen Stat 110 before the term starts
Stat 111 assumes the named distributions, conditioning instincts, and expectation tools of 110 are still warm. A one-week review of distribution stories and Bayes' rule pays off all semester.
- 2
Interrogate every interval and test verbally
Write in plain English what each confidence interval and p-value claims — and what it doesn't. The conceptual misstatements are exactly what exam questions are engineered to catch.
- 3
Work the likelihood from scratch each time
For every model you meet, write the likelihood, log it, and maximize it by hand at least once. The mechanical fluency frees attention for the judgment questions layered on top.
- 4
Compare Bayesian and frequentist answers side by side
Running both analyses on the same problem and explaining where they differ is the deepest comprehension check the course offers — and a recurring exam format.
- 5
Keep inference instincts warm with Fennie
Upload the Stat 111 syllabus and Fennie's Daily Plan schedules spaced problem practice with 110-review woven in early, plus quizzes on the interpretation traps generated from your actual course materials. Free to start.
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How Fennie helps with STAT 111
Fennie's Daily Plans schedule Stat 111 as spaced problem practice with Stat 110 review woven into the early weeks, when the probability tools need to be warm. Chat through what a confidence interval actually claims, and drill the interpretation questions where exam points concentrate.
FAQ
Is Stat 111 harder than Stat 110?
Different hard — the problem-solving creativity carries over, but inference adds a conceptual layer about what statistical statements mean. Students who only computed in 110 feel the difference.
Do I need Stat 110 before Stat 111?
Yes — 111 builds directly on 110's distributions, conditioning, and expectation toolkit. Taking them back to back keeps the probability fresh.
Is Stat 111 useful for data science?
Very — estimation, testing, and Bayesian reasoning are the inferential core under every applied method. It pairs naturally with CS 109A's applied workflow.
Pass STAT 111 with a plan, not a cram
Upload your STAT 111 materials and Fennie generates a Daily Plan paced to your deadline — plus chat, flashcards, and quizzes built from the actual course content.
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