Changes in version 2.0.0                        

A major release that tailors the package to the 4th edition of Maxwell,
Delaney, and Kelley, Designing Experiments and Analyzing Data: A Model
Comparison Perspective (2026, Routledge).

Data

  - The data sets now correspond to the 4th edition of the book: the
    chapter tables, the end-of-chapter exercises, and the tutorials.
    Each data set continues to ship under both its long name (e.g.,
    chapter_1_table_1) and its short alias (e.g., C1T1), and the numeric
    coding of variables is preserved so the book's model-comparison and
    contrast examples reproduce exactly.
  - Several data sets were renamed so their numbers match the 4th
    edition's table numbering, which shifted relative to earlier
    printings: chapter_7_table_15 becomes chapter_7_table_16,
    chapter_7_table_23 becomes chapter_7_table_24, chapter_9_table_11
    becomes chapter_9_table_12, chapter_12_table_21 becomes
    chapter_12_table_29, chapter_13_table_5 becomes chapter_13_table_6,
    chapter_13_table_12 becomes chapter_13_table_10, and the split-plot
    reaction-time tables chapter_14_table_8 and chapter_14_table_10
    become chapter_14_table_7 and chapter_14_table_9. Only the names
    changed; the data values are identical. The short aliases were
    renamed to match (for example, C7T15 becomes C7T16).
  - Added the transformed-score data sets the 4th edition reports
    alongside the split-plot example: chapter_14_table_8 (the M and D
    scores for the data in Table 14.7) and chapter_14_table_10 (the M,
    D1, and D2 scores for the data in Table 14.9), each also under its
    short alias (C14T8, C14T10).
  - Removed chapter_13_table_14 (and its alias C13T14). Its slope and
    linear-trend scores correspond to a 3rd-edition table that is not
    part of the 4th edition; the linear-trend values it tabulated remain
    available as the Linear column of chapter_13_table_10.
  - Removed chapter_4_table_7 (and its alias C4T7). It held data for a
    3rd-edition demonstration that the sums of squares of orthogonal
    contrasts are additive while those of nonorthogonal contrasts are
    not; in the 4th edition that demonstration moved to the online
    supplement (designingexperiments.com/supplements), so the data set
    no longer corresponds to a printed table. The 4th edition's printed
    Table 4.7 is the Exercise 11 data, which is already shipped as
    chapter_4_exercise_11.
  - Corrected the content of chapter_7_table_9 (and its alias C7T9). It
    had held a 36-row combined data set (the Table 7.5 blood-pressure
    data with a sixth observation appended to each cell). The 4th
    edition's Table 7.9 is instead the six additional observations
    themselves (one per cell), so the data set now holds those six rows.
    Stacking them onto chapter_7_table_5 with rbind() recreates the
    six-per-cell data whose cell and marginal means are reported in
    Table 7.10.
  - For the data exactly as distributed with the 3rd edition (2018),
    install the archived CRAN release 1.0.2:
    remotes::install_version("AMCP", "1.0.2").

Documentation

  - Corrected the Variables lists in several help pages that had been
    copied from the wrong data set, so the documented variables now
    match the shipped columns: chapter_3_table_3, chapter_7_table_11,
    chapter_10_table_9, chapter_11_table_20, and chapter_13_table_10.
  - Fixed assorted spelling and typographical errors in the help text
    and added an inst/WORDLIST for the package's domain vocabulary.
  - The chapter_13_table_10 examples now show how its linear and
    quadratic D variables are formed from the raw three-level data of
    chapter_13_table_2 using the orthogonal-polynomial coefficients of
    Appendix Table A.10.
  - The chapter_7_table_9 examples now show how its six additional
    observations combine with chapter_7_table_5 to reproduce the cell
    and marginal means of Table 7.10.
  - Gave the Feedback and Drug variables of chapter_7_table_5 and
    chapter_7_table_9 informative level labels (Feedback: 1 =
    biofeedback present, 2 = absent; Drug: 1 = X, 2 = Y, 3 = Z),
    matching the labels used in the book's Table 7.10.
  - Every table that was renumbered, corrected, removed, or added for
    the 4th edition now carries a Note on its help page identifying the
    change (and, for a renumbered or reused name, the
    corresponding 3rd-edition name), so readers coming from the 3rd
    edition are not misled by a shifted or reused table number.

Infrastructure

  - Added a testthat (edition 3) test suite that loads every data set,
    checks that the long and short aliases agree, and reproduces several
    numeric results reported in the book (the Chapter 3 one-sample t
    test, the Chapter 13 trend-contrast omnibus F, and the Chapter 9
    Pygmalion heterogeneity-of-regression slopes).
  - Added a vignette, factors-and-coding, with recipes for attaching
    factor labels to the numerically coded variables without changing
    the canonical data, including a worked example confirming that
    relabeling reproduces the book's results.
  - Added a package CITATION file.
  - On attach, the package prints a short startup message noting that
    version 2.x maps to the 4th edition (2026), pointing to news(package
    = "AMCP") for the list of changed tables, and directing 3rd-edition
    (2018) users to the archived remotes::install_version("AMCP",
    "1.0.2").
  - Added the maintainer's web site (https://kenkelley.org/) and the
    book companion site to the package URL field.