conjoint-cleaninglisted

# Conjoint Data Cleaning Expert ## Instructions ### 1. Qualtrics Export Settings and Metadata **Export format:** The right Qualtrics export choice depends on the pipeline. `cjoint::read.qualtrics()` (Method A) hard-errors when the choice-response columns contain text — export **"Use numeric values"** for it. `projoint::reshape_projoint()` parses the chosen profile from a label at the end of the outcome string (default `A`/`B`), and manual reshaping benefits from readable attribute labels — **"Use choice text"** works for those. When unsure, export both versions; they differ only in response coding. If working with non-Latin scripts (Chinese, Korean, Arabic), export as XLSX rather than CSV to avoid UTF-8/ANSI encoding issues. On Windows with East Asian locales, `read.csv()` may still require `Sys.setlocale()` to match the file encoding before import (see `?cjoint::read.qualtrics` East Asian Language Support). **Metadata rows:** Current Qualtrics CSV exports include **3 header rows** before respondent data: (1) variable identifiers, (2) question text/descriptions, (3) ImportId JSON. Legacy exports have 2 rows. The `cjoint::read.qualtrics()` parameter `new.format = TRUE` (set explicitly; default is `FALSE`) handles the 3-row format. For manual import via `readxl::read_excel()` or `readr::read_csv()`, skip the appropriate number of metadata rows after reading headers. **Randomization order columns:** If "Export viewing order data" is enabled, Qualtrics adds `_DO_` columns (e