Data Analysis Plan#
A Data Analysis Plan (DAP) is a lightweight internal document used to track how we structure and analyze data during a project. It serves as a central reference for the team and evolves over time as the analysis progresses.
This is not a formal preregistration or replication package. Instead, it helps coordinate analysis decisions, catch issues early, and make handoffs or writeups easier.
Context#
The term DAP can mean different things depending on where it appears:
- In a project proposal, it’s a detailed plan of methods and outcomes.
- In a paper, it includes all code and materials for reproducibility.
- In our group, a DAP is an evolving planning document focused on:
- What data we have,
- What we want to report or visualize,
- What we plan to analyze and how.
When to Update#
Update the DAP when:
- New data is added
- Variables or codes are revised
- Thematic or analytic structures change
- Preparing for handoff, manuscript writing, or review
Structure#
A DAP in our group should cover the following:
1. Data Sets#
For all data:
- Type and amount (e.g., 50 survey responses, 12 interviews)
- Source and format (e.g., survey CSV export, interview transcripts)
- Data cleaning or preprocessing steps
- Inclusion/exclusion criteria
- Versioning notes (e.g., v3 excludes test participants)
For qualitative data:
- Transcription details (e.g., anonymized, timestamped, AI model used)
- Storage location and format (e.g., Markdown, docx, coded in Atlas.ti)
2. Descriptive Overview / Reporting#
Quantitative:
- Variables used for descriptive statistics
- Grouping/binning strategies
- Planned summary tables or figures
Qualitative:
- Participant or context metadata (if relevant)
- Summary of common patterns or anticipated codes (optional)
3. Analysis#
Quantitative:
- Variables used in models or statistical tests
- Derived or recoded variables
- Planned statistical methods (e.g., regression, clustering)
Qualitative:
- Coding approach (inductive, deductive, hybrid)
- Number of coders and division of labor
- Conflict resolution strategy (e.g., consensus meetings)
- Reference to codebook or thematic documents (include link)
- Reference related work or papers where thematic framing is reused
Example: Quantitative#
(Fake study ChatGPT and I made up for this example)
Study title: LoginUX: Evaluating Usability Tradeoffs in Multi-Factor Authentication
1. Data Sets#
We collected simulated login task data from two participant pools.
Data set LoginUX.mturk#
| Data Set | Initial (mturkRaw) | Drop-Out / Removed (mturkDropout / mturkInvalid) | Valid (mturkValid) |
|---|---|---|---|
| LoginUX.mturk | 183 | 10 / 1 | 172 |
Data set LoginUX.internal#
- Subset
LoginUX.internal.stem - Subset
LoginUX.internal.nonstem
| Data Set | Initial (raw) | Drop-Out / Removed (dropout / invalid) | Valid |
|---|---|---|---|
| LoginUX.internal.stem | 38 | 3 / 2 | 33 |
| LoginUX.internal.nonstem | 10 | 1 / 0 | 9 |
| LoginUX.internal | 48 | 4 / 2 | 42 |
Combined valid:
totalValid = mturkValid + internalValid = 172 + 42 = 214
2. Descriptive Overview / Reporting#
-
Demographics:
- Age groups: 18–24, 25–34, 35–49, 50+
- Gender: F / M / Other
- Technical background: STEM / Non-STEM
-
Task structure:
- Participants completed three login tasks (SMS, App, WebAuthn)
- 10-item SUS after each task
- Open-ended feedback at session end (stored separately)
-
Planned outputs:
- Task completion time by method (boxplots)
- SUS score distributions by method and background
- Error types per method
3. Analysis#
-
Key variables:
- Dependent:
sus_score - Independent:
method,tech_background,task_order - Derived:
task_success(boolean: true if task completed)interaction_time(log-transformed total time)
- Dependent:
-
Planned models:
- Mixed-effects:
sus_score ~ method + tech_background + (1 | participant_id) - Logistic regression:
task_success ~ method + tech_background - Exploratory: ANOVA on
interaction_time - Holm-Bonferroni correction for post-hoc comparisons
- Mixed-effects:
Example: Qualitative#
(Fake study ChatGPT and I made up for this example)
Study title: DevPass: Developer Attitudes Toward Password Managers in Practice
This study combines two qualitative data sources to examine how developers perceive, adopt, and discuss password manager use: (1) semi-structured interviews, and (2) analysis of public GitHub issue threads in developer-facing security tools.
1. Data Sets#
Interviews:
- 18 conducted; 15 included in analysis (2 audio issues, 1 withdrawn)
- Length: 35–60 minutes
- Format: Verbatim, manually transcribed, anonymized
- Storage: Markdown files in
data/interviews/, tracked ininterview_index.md
GitHub Issues:
- 102 issues sampled from 6 open-source repositories tagged with authentication- or password-related labels (e.g., “auth”, “security”, “password”)
- Repositories selected based on usage of password managers or integration with external credential stores
- Thread data exported using GitHub API, manually cleaned, and stored in
data/issues/as Markdown - Inclusion criteria: technical relevance, non-duplicate, at least one substantive comment
2. Descriptive Overview / Reporting#
Participants (interviews):
- Metadata collected: role, experience level, company size, password manager use
- Grouped summaries by adoption status and technical background
Artifacts (issues):
- Metadata recorded: repo name, issue date, number of comments, tags
- Manual labeling of issue type (bug, feature, integration, user confusion, etc.)
Planned descriptive outputs:
- Quote-driven overview of perceived barriers to adoption
- Common failure points and integration problems from GitHub threads
- Summary counts: tools mentioned, integration types, and usability complaints
3. Analysis#
Coding strategy:
- Hybrid inductive/deductive approach
- Initial codebook derived from prior usable security studies (e.g., adoption frameworks, tool trust factors)
- Codebook refined iteratively and versioned in
codebook_v3.md
Process:
- Interviews and issues coded using the same code set with source-specific annotations
- Two coders (C1, C2), overlapping on 25% of the data
- Disagreements discussed in calibration meetings; consensus coding applied before theme development
Theme construction:
- Themes developed jointly across both sources
- Special attention to cross-source convergence (e.g., when interview complaints match public support patterns)
- Candidate themes documented in
themes_v2.mdwith representative quotes from both data types
Related literature:
- Supporting citations and reused framing concepts from prior work documented in
related_work.md - Includes quote excerpts from existing studies for thematic comparison