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R-MORIE (Multi-domain Open Research and Inferential Estimation) is an R package for causal inference, sampling, psychometrics, point-process modeling, and criminological accountability analysis, with no Python dependencies.

Statement of need

Applied observational research on Canadian carceral, policing, and oversight data usually means stitching together a dozen single-purpose packages — one for difference-in-differences, one for propensity-score matching, one for spatial scan statistics, one for self-exciting point processes — each with its own data contract, and none aware of the survey-weighting, provenance, and privacy constraints these data carry. rmorie is for criminologists, quantitative social scientists, and accountability researchers who need those estimators in one consistent, provenance-preserving toolkit, with the MRM (Multilevel Reconciliation Methodology) framework as its motivating application. Every public function is prefixed morie_* so it composes safely alongside the specialist packages it wraps, and results carry the labeling that keeps synthetic development runs from being mistaken for inferential findings. Primary methodological references for each estimator family are listed in the package-level help (?rmorie).

Documentation

With over 13,000 exported functions, the full reference is large — use the manual or the package site above rather than scrolling the function index. This README covers install + the most common workflows only.

Why rmorie?

rmorie is a self-contained research toolkit: every statistical algorithm in the package — matching (nearest-neighbour, Mahalanobis, exact, CEM, optimal, genetic, cardinality), design-based IPW and doubly-robust estimation, double machine learning, causal forests and meta-learners, causal DAGs with identification and refutation, the full quasi-experimental family (DiD incl. Callaway-Sant’Anna, event studies, synthetic control and synthetic DiD, RDD, interrupted time series, IV), item-response theory, geostatistics, digital signal processing, Hawkes processes, cryptographic hashing with post-quantum primitives, and the data-access parsers — is implemented natively in this package’s R and C++. rmorie does not call MatchIt, survey, DoubleML, grf, dagitty, did, fixest, rdrobust, ivreg, psych, gstat, spdep, signal, wavelets, digest, or openssl at runtime. This means:

  • No upstream breakage. A major release of any of those packages cannot change rmorie’s results. A paper run in 2026 reproduces identically in 2030.
  • Validated, not just reimplemented. Every native engine is cross-validated in tests/cross/ against its reference package — to machine precision where the estimand is deterministic (see the table below) — and benchmarked in inst/benchmarks/.
  • Composable workflows. Matchers, ATE/CATE/DiD estimators, and the DAG pipeline share one class system with common print(), summary(), and reporting methods; the phase-17 composition test runs DAG -> identification -> matching -> DML -> refutation -> publication table end to end in one suite.
  • Category-integrity guards. morie_safe_recode(), morie_safe_factor(), morie_audit_categories(), and morie_crosstab_verify() make the silent category-mapping errors that have corrupted published disparity analyses structurally impossible in an rmorie workflow.

Packages in Suggests play three roles, and no others:

  1. Reference implementations for tests/cross/. The packages the native engines replace (table below) are loaded only by the cross-validation tests; an installed copy never changes a result.
  2. Named pass-throughs, opt-in by name. A few functions exist to hand a call to another package and say so in their name and help page: morie_geostat_variogram() / morie_geostat_krige() (gstat), morie_copula_*() (copula), morie_kernel_pca() / morie_spectral_cluster() (kernlab), morie_meta_rma() (metafor), morie_mvnorm_*() (mvtnorm), morie_causal_impact() (CausalImpact), and morie_causal_weighting() for a weighting method without a native engine (WeightIt). The native counterparts are morie_spatial_variogram(), morie_spatial_krige(), morie_meta_random_effects(), morie_weight_*() and so on.
  3. Integrations outside the statistical engines: plotting (ggplot2), databases (DBI, RSQLite, duckdb, bigrquery), Bayesian back ends (brms, rstanarm, cmdstanr), deep learning (torch, reticulate), spatial file formats (sf) and reading binary .xls workbooks (readxl). A function that needs one says which, and how to install it, when it is missing.

Cross-validation at a glance

Family Replaces Validation
Matching (10 methods: nearest, variable ratio, exact, CEM, Mahalanobis, optimal pair, optimal full, subclass, genetic, cardinality) MatchIt, optmatch, Matching, designmatch pair-identical (nearest, variable ratio, subclass) or the optimum itself (optimal, full)
IPW / design-based mean + GLM (strata, clusters, fpc) survey svymean / svyglm estimates + SEs to 1e-12
DML (PLR + IRM) DoubleML/mlr3 CI-overlap agreement; 40-60x faster
Causal forest / meta-learners grf CATE agreement; 1.5-2.9x faster
DAG identify/estimate/refute dagitty, DoWhy adjustment sets == dagitty on every graph tested
DiD family (TWFE/event/CS/DR/Bacon/DID-M/feTR) fixest, did, DRDID, bacondecomp, DIDmultiplegt, TwoWayFEWeights coefficients, SEs, and influence functions to 1e-8-1e-10
Synth control + SDID Synth/coresynth recovers simulated truths; placebo inference built in
RDD (IK bw, sharp/fuzzy/kink, McCrary) rdrobust, rdd point estimates == rdrobust at fixed h to 1e-8
IV (2SLS/LIML/GMM) + ITS AER, ivreg, gmm 2SLS == ivreg + sandwich HC1 to 1e-8
IRT (2PL/GRM/EAP) + psychometrics psych, mirt KMO == psych to 1e-8; 2PL vs mirt within 0.1
Geostatistics (variogram/kriging) gstat, spdep kriging == gstat to 1e-6; Moran variance == spdep
DSP (Butterworth/FIR/Welch/DWT) signal, wavelets butter coefficients == signal to 1e-8; DWT perfect reconstruction
Hawkes MLE hawkes exponential-kernel loglik == hawkes
SHA-256/HMAC/PBKDF2 + PQC digest, openssl NIST FIPS + RFC vectors bit-for-bit; ML-KEM/ML-DSA/SLH-DSA/HQC via liboqs
Parsers (JSON/XML/HTML/Parquet) jsonlite, xml2, arrow jsonlite-parity outputs; accelerators optional
Weighting family (ps/entropy/CBPS/OW/stabilized/SuperLearner) WeightIt, CBPS glm weights == WeightIt to 1e-8; CBPS moments < 1e-6
Modern staggered DiD (Sun-Abraham/Borusyak/did2s) did2s, didimputation point estimates within 0.02 of did2s
Unified front-ends (morie_did/morie_iv_2sls/morie_rdd) did, AER, rdrobust CS overall == did::aggte to 0.1; 2SLS == ivreg to 1e-6
Crim methods (ETAS/multivariate Hawkes/Knox/RTM) (papers) recovers simulated truths; Knox permutation calibrated

What rmorie is NOT

rmorie is not a wrapper. At runtime it does not call:

  • MatchIt / optmatch / Matching / designmatch (matching) — replaced by morie_matching_*
  • WeightIt / CBPS (propensity weighting) — replaced by morie_weight_*
  • survey (design-based estimation) — replaced by the native svyglm engine behind morie_ipw_* / morie_ebac_*
  • DoubleML / mlr3 (double machine learning) — replaced by the native PLR/IRM/PLIV cross-fit engines
  • grf / EconML-style learners (heterogeneous effects) — replaced by the native causal forest and T/S/X/DR meta-learners
  • dagitty / DoWhy (DAGs, identification, refutation) — replaced by morie_dag_*
  • did / fixest / did2s / didimputation (modern DiD) — replaced by morie_did_* with auto-dispatch to Callaway-Sant’Anna, Sun-Abraham, Borusyak, and Gardner two-stage
  • rdrobust (RDD) — replaced by morie_rdd (IK bandwidth + McCrary + placebo cutoffs bundled)
  • Synth (synthetic control) — replaced by morie_synth_control with built-in placebo inference
  • AER / ivreg (IV) — replaced by morie_iv_2sls with the Staiger-Stock refusal gate
  • psych / mirt (psychometrics) — replaced by morie_psymet_* and morie_irt_*
  • gstat / spdep (geostatistics) — replaced by the native variogram/kriging/GWR stack
  • signal / wavelets (DSP) — replaced by rgfir/rgiir/rgwav and morie_dsp_*
  • hawkes (point processes) — replaced by the native C++ Hawkes kernel family + morie_crim_etas / morie_crim_hawkes_multivariate
  • digest / openssl (hashing/KDF) — replaced by the native C++ SHA-2/HMAC/PBKDF2 + liboqs PQC
  • jsonlite / xml2 / arrow / readxl as requirements (parsing) — replaced by morie_fetch_* native parsers and the package’s own .xlsx reader (those packages remain optional fast paths; readxl is needed only for the old binary .xls format)

Those packages appear in Suggests so that tests/cross/ can prove, on every CI run, that the native engines match them; the named pass-throughs and integrations listed above are the only other uses of Suggests.

What’s new in 1.4.0

Everything since 1.3.4, in one place; NEWS.md has the release-by-release detail.

  • 5,000+ exported functions, every one tested: 5,189 morie_* entry points (13,655 exports in all), each with a test that recomputes its value, and the same names in the Python package morie, checked against each other in CI.
  • Criminology research programme: the open-problems ledger under research/, implemented as package functions with Lean 4 proofs of the identification results (264 theorems, 0 sorry): DerSimonian-Laird pooling, separation in a logistic fit, Imbens-Manski intervals for partially identified sentencing effects, the Cheeger bound on a hot-spot boundary, Duncan-Davis bounds, monotone treatment selection, near-repeat extinction, judge-leniency designs, the Oaxaca-Blinder decomposition, Little’s law on a docket and the incapacitation identity. The Python package carries every research function at parity.
  • Native causal-inference engines: matching, double machine learning, causal forests, meta-learners, design-based GLM and the morie_dag* toolkit, cross-validated against MatchIt, DoubleML, grf and dagitty.
  • Ask a model: the model you bring (a provider’s key, an OpenAI-compatible server of your own, or a local Ollama), answering from the packages’ help; a keyword fallback needs no network. See Ask a model and sign in below.
  • The full command line in R: install_cli() puts rmorie on your PATH, with every verb of the Python command line: login, doctor, models, ask, analyze, list-modules, run-module, list-datasets, pull, provider, cheatsheet, selftest, pipeline, emissions, verify-pollution, crypto, ingest. It runs under R 4.6.
  • Data: the curated tables at https://data.rmorie.com (175 databases and 716 tables on 2026-10-13, among them the Health Infobase tables and the OTIS research environments) open with a personal key: rmorie login signs in with GitHub or an emailed code, or ask at https://rmorie.com/access; the terms are at https://rmorie.com/data-license, and the ICPSR, NCVS 38604 and a2aj tables open once you accept theirs at https://data.rmorie.com/terms; built-in datasets come through rmoriedata (r-universe), fetched with provenance by rmoriebricklayer (r-universe); module runs fall back to rmoriedata’s synthetic CPADS PUMF.
  • Pollution and compute emissions: the pollution-health module and a compute-emissions tracker with a C++ background sampler and signed bricklayer capsules are native R.
  • SIU subsystem: the Ontario Special Investigations Unit director’s-report corpus (English + French, 2005-present). See SIU pipeline below.
  • Also: CPADS contract helpers, IPW / eBAC workflows, outputs-manifest tooling, synthetic data generators, a C/C++ backend for the Hawkes likelihoods and the SIU parser, the causal-taphonomy suite, the A2AJ / CanLII Canadian legal-data ingest, and agent() to call the rmorie CLI agent from R (agent_available() probes for it).
  • Quality: every finding of the fresh-user test rounds is fixed with a test, every example runs without warnings, and the test harness runs in one process under covr and on Windows.

Scientific guardrail

  • Synthetic data is for development, testing, demos, and CI only.
  • Final inferential or policy-facing results must be produced from approved real data with full provenance.
  • Synthetic runs must be explicitly labeled as synthetic in outputs and reporting text.

Install

From r-universe (prebuilt binaries for macOS and Windows, a source build on Linux). Its companions, rmoriebricklayer >= 0.5.14 and rmoriedata >= 0.3.7, come from r-universe too: CRAN carries older versions. Naming them replaces an older copy already installed.

With pak (progress bars, parallel downloads, compiler output hidden unless a build fails, and the named packages always upgraded to the current release):

if (!requireNamespace("pak", quietly = TRUE)) {
  install.packages("pak", repos = "https://cloud.r-project.org")
}
pak::repo_add(rootcoder007 = "https://rootcoder007.r-universe.dev")
pak::pkg_install(c("rmoriebricklayer", "rmoriedata", "rmorie"))

# want every optional package too, in one shot? add dependencies = TRUE
# (large: compiles many specialist packages; see "Optional packages" below)
pak::pkg_install("rmorie", dependencies = TRUE)

From a terminal (single quotes outside, double quotes inside, so the shell passes the R code through untouched):

Rscript -e 'if (!requireNamespace("pak", quietly = TRUE)) install.packages("pak", repos = "https://cloud.r-project.org"); pak::repo_add(rootcoder007 = "https://rootcoder007.r-universe.dev"); pak::pkg_install(c("rmoriebricklayer", "rmoriedata", "rmorie"))'

Without pak, plain install.packages() does the same with R’s own output. Keep repos: under Rscript there is no mirror chooser, and a bare call stops with “trying to use CRAN without setting a mirror”.

Rscript -e 'install.packages(c("rmoriebricklayer", "rmoriedata", "rmorie"), repos = c("https://rootcoder007.r-universe.dev", "https://cloud.r-project.org"))'

From GitHub (a source build; needs a C/C++ toolchain):

Rscript -e 'if (!requireNamespace("pak", quietly = TRUE)) install.packages("pak", repos = "https://cloud.r-project.org"); pak::repo_add(rootcoder007 = "https://rootcoder007.r-universe.dev"); pak::pkg_install("rootcoder007/rmorie")'
# without pak
Rscript -e 'repos <- c("https://rootcoder007.r-universe.dev", "https://cloud.r-project.org"); install.packages("remotes", repos = repos); remotes::install_github("rootcoder007/rmorie", repos = repos, upgrade = "always")'

From a clone, at the repository root:

pak::repo_add(rootcoder007 = "https://rootcoder007.r-universe.dev")
pak::local_install()
# without pak
install.packages(c("rmoriebricklayer", "rmoriedata"),
                 repos = c("https://rootcoder007.r-universe.dev", "https://cloud.r-project.org"))
install.packages(".", repos = NULL, type = "source")

On macOS, CRAN’s R (from https://cloud.r-project.org/bin/macosx/) installs r-universe’s prebuilt binaries in seconds. Homebrew’s R cannot use them, so there every package is compiled from source.

The assistant (morie_llm_ask()) asks the model you bring (a provider’s key, your own OpenAI-compatible server, or a local Ollama; see Ask a model and sign in), and falls back to a keyword answer that needs no network.

Optional packages (the R equivalent of pip install pkg[extra])

The base install is complete for every statistical workflow — the native engines need nothing beyond the hard dependencies. Suggests entries are (a) reference packages used only by the cross-validation tests in tests/cross/, and (b) optional accelerators (e.g. jsonlite/xml2/arrow fast paths for the parsers, ML backends). Every optional-path function tells you what to install when it’s missing, and the test suite skips (never fails) without them. To provision the extras up front:

# install every optional package rmorie can use (one-time, ~15 min)
morie_install_extras(which = "all", ask = FALSE)

# or just what's missing, interactively
morie_install_extras()

# or a specific family, e.g. machine learning
morie_install_extras(which = c("randomForest", "glmnet", "xgboost",
                               "ranger", "caret", "pROC"))

Common families: ML (randomForest, glmnet, xgboost/gbm, ranger, caret, pROC, Rtsne, e1071, dbscan), DSP (signal, pracma, wavelets), causal (DoubleML, mlr3, mlr3learners, ivreg, fixest), storage (RSQLite, duckdb).

Ask a model and sign in

morie_llm_ask() asks the model you set up, through rmoriebricklayer, in its automatic order: your own OpenAI-compatible endpoint, then each provider whose key is set (OPENAI_API_KEY, ANTHROPIC_API_KEY, GEMINI_API_KEY, OPENROUTER_API_KEY, GROQ_API_KEY, …), then a local Ollama. Nothing is hosted for you, and no prompt goes anywhere you did not set up. The model gets the help of rmorie, rmoriedata and rmoriebricklayer, with tools to search and read it; with no model set up, the answer comes from a keyword index.

The sign-in is for the curated tables only: a personal key for data.rmorie.com, which the Python package morie reads too.

morie_llm_config(route = "anthropic")              # with ANTHROPIC_API_KEY set; rmoriebricklayer::bricklayer_llm_providers() lists them
morie_llm_provider_set("http://localhost:1234/v1", model = "local-model")   # your own server (LM Studio, vLLM, llama.cpp)
morie_llm_ask("Which design fits a pre/post comparison with a control group?")
morie_llm_login()                                  # the data key: GitHub sign-in
morie_llm_login(email = "you@example.com")         # an emailed code instead
morie_llm_login(token = "sk-...")                  # a key you were given
morie_hosted_datasets()                            # curated db/table keys
df <- morie_load_hosted_dataset("chicago_crime/incidents")
morie_llm_logout()

From the shell, after install_cli():

rmorie config setup                           # pick a provider, paste its key, choose a model
rmorie models                                 # the models your route offers
rmorie ask "What does the power-design module compute?"
rmorie doctor                                 # which route ask takes from this machine
rmorie login                                  # the data key: GitHub sign-in
rmorie login --email you@example.com          # an emailed code instead: type it at the prompt
rmorie login --no-browser                     # server / SSH: prints a link + code to open on any device
rmorie login --token                          # paste a key you were given

Outputs-manifest example

library(rmorie)

# a project that keeps data/manifest/outputs_manifest.csv (morie_build_outputs_manifest() writes one)
manifest <- morie_read_outputs_manifest(project_root = "/path/to/project")
audit    <- morie_audit_public_outputs(project_root = "/path/to/project",
                                       manifest     = manifest)
morie_summarize_output_audit(audit)

Synthetic data example

library(rmorie)

synthetic_path <- morie_write_synthetic_data(
  path      = "data/private/synthetic_study_data.csv",
  n         = 8000,
  seed      = 2026,
  overwrite = TRUE
)

Cross-project adaptation

library(rmorie)

name_map <- morie_default_synthetic_name_map("generic")
name_map["cannabis_use"] <- "exposure_any"
name_map["bac"]          <- "outcome_continuous"

dat <- morie_generate_synthetic_data(
  n        = 5000,
  seed     = 1,
  name_map = name_map
)

SIU pipeline

rmorie ships the first open-source parser and data-mining subsystem for the Ontario Special Investigations Unit (SIU) director’s-report corpus — created by Vansh Singh Ruhela as part of the MORIE / R-MORIE ecosystem and the MRM (Multilevel Reconciliation Methodology) framework. To our knowledge no prior public, open-source SIU director’s-report parser or automated SIU data-mining engine existed in Canada; the SIU publishes the reports, but there was no programmatic pipeline to fetch, parse, and analyse them at corpus scale until this one.

A first-class subsystem for the Ontario Special Investigations Unit director’s-report corpus. The fetcher handles both English and French templates from 2005 onward across all three of the site’s historical layout generations (pre-2017 Attorney-General releases, the 2017-2019 transitional format, and the post-2019 SIU Act template); the parser extracts the report fields (police service, incident/notification/ decision dates, investigator and witness/subject-official counts, affected-person demographics, injuries, legislation, charges verdict, and director’s decision) and is hand-rolled for correctness under SIU’s heterogeneous markup.

Since 1.1.4 the subsystem is layered on the compiled SIU core in ‘rmoriebricklayer’ and the verified corpus shipped by ‘rmoriedata’ (0.3.4): a 66-column table of 4,613 reports, 2,309 English and 2,304 French, whose English entries were read and cross-audited by a multi-agent review panel (a French report carries its English report’s reviewed case facts) (every subject-official count verified; the mechanical resolver scores zero wrong against it). morie_siu_reports() returns that corpus verbatim and only ever fetches/parses reports newer than it; morie_siu_resolve_so(report_text) resolves the subject-official count from a report’s text, the verified corpus first, then the compiled rule engine; morie_siu_panel() runs the same Mixture-of-Agents reading panel on new reports through any Ollama-compatible endpoint you point it at (your models, your host — no hardcoded default).

The subsystem powers downstream MRM analyses — Hawkes self-exciting point processes, causal estimators, fairness audits, and the physics- of-crime modules — on Canadian police-oversight data.

Key entry points: morie_siu_reports(), morie_siu_resolve_so(), morie_siu_panel(), morie_siu_parse_report(), plus the legacy fetch path morie_fetch_siu(), morie_siu_index_url(), morie_siu_refresh_manifest(), morie_siu_audit_case(), morie_siu_sanity_check(), morie_siu_all_analyses().

Fetch and parse the full corpus

library(rmorie)

# Prefer the panel-verified corpus (4,613 reports x 66 columns, 2,309 English
# entries human+multi-agent reviewed, French rows carrying their facts) — no re-fetching:
df <- morie_siu_reports(update = FALSE)

# The legacy live fetch remains available:
# df <- morie_fetch_siu(lang = "en", cache_html = TRUE, rate_limit = 4)
nrow(df)

Audit a single case

# Inspect parser row + raw HTML + cleaned text side-by-side.
morie_siu_audit_case("17-OVI-201")

# Per-field "does the HTML actually support this value?" check.
morie_siu_anomaly_check("17-OVI-201")

# Diff parser output against an external table.
# field_map maps the external table's columns to parser fields; external_case_col names its case column
morie_siu_compare(
  case_number       = "17-OVI-201",
  external          = my_other_table,          # e.g. data.frame(case_number = "17-OVI-201", n_officers = 2L)
  field_map         = list(n_officers = "number_of_officers_involved"),
  external_case_col = "case_number"
)

AI extraction (free local model by default)

# Default: local Ollama with gemma3:4b. No API key required.
morie_siu_llm_extract("17-OVI-201")

# An explicit chain: local first, then the model you set up for rmoriebricklayer (`route`), then Gemini.
morie_siu_llm_extract("17-OVI-201", model = c("ollama", "route", "gemini"))

# French to English translation of the cached reports (field by field, via the local model).
morie_siu_translate(target_lang = "en", case_numbers = "26-OCI-168")

Supported providers: ollama (default), route (the model you set up: a provider’s key or your own server; a provider id such as anthropic or groq names one), gemini, claude, vertex, openai, openai_compatible. Environment knobs: OLLAMA_HOST (defaults to http://localhost:11434), OLLAMA_MODEL (defaults to gemma3:4b), OLLAMA_KEEP_ALIVE (30m), GEMINI_API_KEY.

Format-validity sweep

df   <- morie_siu_reports()        # the reviewed corpus, from rmoriedata (r-universe)
sane <- morie_siu_sanity_check(df)  # one row per report, with its format issues (if any)
table(sane$issues_count > 0)        # regex / ISO date / yes-no / chrome leak; older reports leave many fields blank
head(sane$issues[sane$issues_count > 0], 3)

Aggregate accuracy

# How accurate is each column across a sample of cases?
df <- morie_siu_reports()
morie_siu_audit_columns(case_numbers = sample(df$case_number[nzchar(df$case_number)], 50))

Canonical override system

The parser learns. Ship-time corrections live in inst/extdata/siu_canonical_overrides.csv.gz (47 hand-verified corrections covering 10 spot-checked cases). Users can add their own:

morie_siu_record_correction(
  case_number    = "20-OFD-082",
  field          = "number_of_officers_involved",
  verified_value = "3 SO"
)

Overrides are applied automatically at the end of morie_fetch_siu(), per cell, by case number.

Inspect the manifest

manifest <- morie_siu_index()
table(manifest$`_language`)  # en=2532, fr=2217, other=0

Continuous integration

The R CMD check matrix covers six cells, all green on main:

Platform R version
macos-latest release
windows-2025 release
ubuntu-latest release
ubuntu-latest release + postgres-15
ubuntu-latest oldrel-1
ubuntu-latest devel

Plus: pkgcheck, covr + Codecov upload, lintr, goodpractice, and CodeQL.

Citation

If you use rmorie in your research, please cite the software:

Ruhela, V. S. (2026). rmorie: Multi-domain Open Research and Inferential Estimation in R. https://github.com/rootcoder007/rmorie

BibTeX (or run citation("rmorie") after installation for the entry stamped with the exact installed version, sourced from inst/CITATION):

@Manual{ruhela_rmorie_2026,
  title   = {rmorie: Multi-domain Open Research and Inferential Estimation in R},
  author  = {Ruhela, Vansh Singh},
  year    = {2026},
  url     = {https://github.com/rootcoder007/rmorie}
}

See CITATION.cff for the machine-readable metadata GitHub’s “Cite this repository” button uses.

License

R-MORIE is licensed under AGPL-3.0-or-later. See LICENSE for the full text and LICENSING.md for the per-component breakdown.

Bayesian priors

rmorie’s Bayesian regression (morie_bayes_lm) places zero-mean Normal priors on the regression coefficients; the prior_sd argument is the prior standard deviation (the scale of plausible coefficient values). Larger prior_sd is weakly informative; smaller values pull estimates toward zero (regularisation). Example:

d <- data.frame(x = rnorm(100)); d$y <- 1 + 2 * d$x + rnorm(100)
# weakly-informative prior (sd = 10) vs a tight regularising prior (sd = 0.5)
fit_weak  <- morie_bayes_lm(y ~ x, d, prior_sd = 10)
fit_tight <- morie_bayes_lm(y ~ x, d, prior_sd = 0.5)

See the bayesian-priors vignette for applied guidance.