Categorical Data Analysis 2024/25

Outline of lecture

1. Discrete distributions [code for/from lecture]

2. Maximum Likelihood Estimation (MLE) [code for/from lecture]

3. Goodness of fit (GoF) [code for/from lecture] [info about goodfit]

4. Contingency tables:

   • Simpson's paradox [code for/from lecture]
   • Contingency tables and Cramer's V [code for/from lecture]

5. Categorical data in regression [code for/from lecture]

6. Generalized linear models:

   • Logistic regression [code for/from lecture]
   • Poisson and Negative binomial regression [code for/from lecture]
   • Zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) [code for/from lecture]
   • Hurdle Poisson (HP) and Hurdle negative binomial [code for/from lecture]

7. Generalized estimating equations [code for/from lecture]

Case study

• case study task description
• dataset

Example final test

Here is an example of the final test.

Required packages / modules

• R:
  • distributions3,
  • maxLik, rootSolve
  • vcd, fitdistrplus
  • marginaleffects, modelsummary
  • car
  • see, performance, patchwork
  • geepack
• Python:
  • scipy, numpy, pandas
  • pingouin, matplotlib, statsmodels
• Julia:
  • Distributions.jl, DataFrames.jl,
  • Optim.jl, Roots.jl
  • HypothesisTests.jl, StatsBase.jl
  • FreqTables.jl, CSV.jl
  • Effects.jl
  • GLM.jl

Description of the data

Source:

• id -- company identifier
• woj -- region (województwo) id (02, 04, ..., 32)
• public -- is the company public (1) or private (0)?
• size -- size of the company (small = up to 9 employees, medium = 10 to 49, big = over 49)
• nace -- NACE (PKD) sections (1 letter)
• nace_division -- NACE (PKD) division (2-digits, https://www.biznes.gov.pl/pl/klasyfikacja-pkd)
• vacancies -- how many vacancies the company reported?

Sample rows from the dataset

           id woj public   size nace nace_division vacancies
    1:  27350  14      1  Large    O            84         2
    2:  26705  14      1  Large    O            84         1
    3: 257456  24      1  Large    O            84         2
    4: 183657  16      1 Medium    O            84         0
    5: 200042  18      1 Medium    O            84         0
   ---                                                      
57476: 244800  08      1 Medium    P            85         0
57477:  62309  08      1 Medium    R            93         0
57478: 106708  08      0 Medium    B            08         0
57479:  62264  08      0 Medium    B            08         0
57480: 255865  08      0  Small    C            23         0

Software versions

R version 4.4.2 (2024-10-31)

Python 3.12.7 | packaged by Anaconda, Inc. | (main, Oct  4 2024, 08:22:19) [Clang 14.0.6 ]

Julia Version 1.11.3
Commit d63adeda50d (2025-01-21 19:42 UTC)