Publications by Pengcheng Zhai
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Chapter 6 - The Haunted DAG & The Causal Terror Multiple regression is no oracle, but only a golem. It is logical, but the relationships it describes are conditional associations, not causal influences. Therefore additional information, from outside the model, is needed to make sense of it. This chapter presented introductory examples of some com...
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Chapter 7 - Ulysses’ Compass The chapter began with the problem of overfitting, a universal phenomenon by which models with more parameters fit a sample better, even when the additional parameters are meaningless. Two common tools were introduced to address overfitting: regularizing priors and estimates of out-of-sample accuracy (WAIC and PSIS)...
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Chapter 12 - Monsters and Mixtures This chapter introduced several new types of regression, all of which are generalizations of generalized linear models (GLMs). Ordered logistic models are useful for categorical outcomes with a strict ordering. They are built by attaching a cumulative link function to a categorical outcome distribution. Zero-inf...
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Be sure to list the group members at the top! This assignment is the first component for your class project. Be sure all group members contribute, and each group member must submit the assignment individually. You can use either R or Python or both for this assignment. You should use the code and packages we used in class assignments, but these c...
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Libraries / R Setup In this section, include the R set up for Python to run. ##r chunk library(reticulate) library(wordnet) library(qdap) ## Loading required package: qdapDictionaries ## Loading required package: qdapRegex ## Loading required package: qdapTools ## Loading required package: RColorBrewer ## ## Attaching package: 'qdap' ## The fo...
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Be sure to list the group members at the top! This part of the project allows you to answer your own questions not covered in one of our assignments. Do not make this analysis extraordinarily complicated! You will just pitch your idea in this session, you will run the analysis in the final report. Subtitles I am using the movie Joker subtitles ...
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Please do not reorder the assignment - fill in each chunk as requested. Load the libraries + functions Load all the libraries or functions that you will use to for the rest of the assignment. It is helpful to define your libraries and functions at the top of a report, so that others can know what they need for the report to compile correctly. ##...
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Load the libraries + functions Load all the libraries or functions that you will use to for the rest of the assignment. It is helpful to define your libraries and functions at the top of a report, so that others can know what they need for the report to compile correctly. Import the separate python file that includes the functions you will need ...
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Virtual Machine Set Up Guide Go to: https://rstudio.thedoomlab.com/auth-sign-in Your log in is: Username: firstname_lastname Password: firstnameidnumber Fill in first and last name with your first and last name, while ID number is your HU ID number. Python Set Up Click on terminal and run the following lines: pip3 install -U spacy==2.2.3 pyth...
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