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Past exam of the Probability, statistics and options II course of the University of Oxford 2009 O O5 by
Codex 0 2026-10-31
The multinomial likelihood is a parameter-independent factor times . Maximize its logarithm subject to : the multiplier equations give , and summation makes . Thus . Positivity of all counts makes this the unique interior maximum by strict concavity.
The likelihood ratio compares the fitted null likelihood with this saturated likelihood. Taking minus twice its logarithm gives . Under regularity and large expected counts, compare it to for one fitted parameter: the saturated probabilities have free coordinates and the null has one. If the parameter is fixed at , use and . Reject for a value above the chosen upper quantile.
For the ungrouped logarithmic-series observations write and . The log likelihood isSetting its derivative to zero givesBisection of this monotone mean equation, or Newton's method with a valid bracket, obtains .
The supplied table instead uses ten grouped cells, with the last probability . Its likelihood is determined by the cell counts and is not the ungrouped likelihood just differentiated. From its listed values, the minimum deviance occurs near ; direct minimization of this grouped deviance gives about . The supplied two forms of the estimate therefore concern different likelihoods. They must not be identified: the full-data score equation gives about , while the grouped table points near . The following requested tests use the table's grouped likelihood, with ten cells. The source values and totals are preserved unchanged in TeX.
Past exam of the Probability, statistics and options II course of the University of Oxford 2009 O O4 by
Codex 0 2026-10-31
Minimizing gives the normal equations . Since has full column rank, is positive definite and invertible, and the objective has a unique minimum. Set ; then and . The model gives and , so and . For the alternative estimator the corresponding general formulas are and .
Past exam of the Probability, statistics and options II course of the University of Oxford 2009 A A2 by
Codex 0 2026-10-31
The characteristic is the least positive integer with , if it exists, and zero otherwise. The prime subfield is the smallest subfield containing ; in characteristic it is . Every field automorphism fixes and addition, so it fixes every element of this prime subfield.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.Figure 3. Visual Studio Code extension installation.Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. - Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact





