Supplementary Files README (v4)

This package contains anonymised materials prepared for editorial and peer-review purposes.

S1_Deidentified_raw_data_v4.csv
- De-identified item-level raw dataset.
- Participant IDs were recoded as P001-P082.
- No direct personal identifiers are included.
- Group labels: Treatment and Comparison.

S2_Processed_analysis_data_v4.csv
- Processed analysis dataset.
- Dimension scores were computed from item means.
- Behavioral engagement = Items 1-4.
- Cognitive engagement = Items 5-9.
- Emotional engagement = Items 10-13.
- Change scores = post-test score minus pre-test score.

Supplementary_Data_Package_S1_S2_v4.xlsx
- Excel version of the data package.
- Contains README, de-identified raw data, processed data, summary checks, and codebook.

S3_Survey_instrument_and_scoring_documentation_v4.docx
- Full Chinese L2 writing engagement questionnaire.
- Includes item wording, response scale, scoring rules, and the ChatGPT writing-feedback prompt checklist.
- No reverse-coded items were used.

S4_Data_collection_and_instructional_protocol_v4_scrubbed.docx
- Data-collection and instructional protocol.
- Documents the treatment and comparison procedures and scoring rules.

S5_Variable_codebook_and_transformation_rules_v4.csv
- Variable definitions, coding schemes, item-to-dimension mapping, and transformation rules.

S6_Statistical_analysis_script_v4.R
- Reproducible R script for scoring, reliability checks, descriptives, mixed ANOVAs, and simple-effect analyses.

Notes on scoring:
- The final scoring model uses a 4/5/4 structure:
  Behavioral engagement = Items 1-4;
  Cognitive engagement = Items 5-9;
  Emotional engagement = Items 10-13.
- All items are scored from 1 to 7, with higher scores indicating stronger engagement.
- No reverse scoring was applied.
