Enum: Direction

How a term entered or came out of an analysis, using one vocabulary for every term type. Both a categorical level on the plus side of a comparison and a continuous term with a positive coefficient are positive. The referenced term's type distinguishes them. For a cell over a product term, this field gives the interaction coefficient's sign, not either component's slope.

It is a sign, not a magnitude: numeric contrast weights are never recorded, and a contrast whose magnitudes matter keeps them in Analysis.definition. There is no value for a zero weight either -- a level the contrast did not weight has no Cell at all.

Only positive and negative are directional. A cell can record no sign three ways -- undirected, held, or extraction_status: not_reported -- and choosing between them is the decision rule in extraction-readme.md §2.

URI: neurostudy:Direction

Permissible Values

Value	Meaning	Description
positive	None	A level on the plus side of the comparison, or a coefficient under which the ...
negative	None	A level on the minus side of the comparison, or a coefficient under which the...
undirected	None	The test yields no per-level sign, so there is none to report
held	None	A level the contrast was taken within, which appears on both sides of t...

Slots

Name	Description
direction	How this cell entered the contrast: the weight's sign for a categorical level...

In Subsets

• mvp
• model_extracted

Identifier and Mapping Information

Schema Source

• from schema: https://neurostuff.org/schemas/neuroimaging-study-storage

LinkML Source

name: Direction
description: 'How a term entered or came out of an analysis, using one vocabulary
  for every term type. Both a categorical level on the plus side of a comparison and
  a continuous term with a positive coefficient are `positive`. The referenced term''s
  `type` distinguishes them. For a cell over a **product** term, this field gives
  the interaction coefficient''s sign, not either component''s slope.

  It is a sign, not a magnitude: numeric contrast weights are never recorded, and
  a contrast whose magnitudes matter keeps them in `Analysis.definition`. There is
  no value for a zero weight either -- a level the contrast did not weight has no
  `Cell` at all.

  Only `positive` and `negative` are directional. A cell can record no sign three
  ways -- `undirected`, `held`, or `extraction_status: not_reported` -- and choosing
  between them is the decision rule in extraction-readme.md §2.'
in_subset:
- mvp
- model_extracted
from_schema: https://neurostuff.org/schemas/neuroimaging-study-storage
rank: 1000
permissible_values:
  positive:
    text: positive
    description: A level on the plus side of the comparison, or a coefficient under
      which the measure rises as the term rises.
    in_subset:
    - mvp
    - model_extracted
  negative:
    text: negative
    description: A level on the minus side of the comparison, or a coefficient under
      which the measure falls as the term rises.
    in_subset:
    - mvp
    - model_extracted
  undirected:
    text: undirected
    description: 'The test yields no per-level sign, so there is none to report. An
      F or chi-square over a factor compares that factor''s levels against each other
      and returns one statistic for the set: every one of its levels takes a cell
      with this value, and a multi-degree-of-freedom interaction F takes it on the
      cell over the product column.

      Not `extraction_status: not_reported`: the sign is not missing from the page,
      it is absent from the test, so there is something to record rather than nothing.
      The post-hoc contrast that would supply one is a different Analysis.'
    in_subset:
    - mvp
    - model_extracted
  held:
    text: held
    description: 'A level the contrast was taken *within*, which appears on **both
      sides** of the comparison and so has no net sign -- "patients versus controls,
      in the task condition" has task on the plus side and the minus side at once.
      Cell that one level and leave its factor''s other levels **absent**, where an
      undirected test cells every level.

      No report, however complete, could sign this cell, which is what separates it
      from both unsigned neighbours: `undirected` is a test that produces no sign,
      a sign the page withheld is `extraction_status: not_reported`, and this is a
      sign that is not defined. A cell that names no level -- on a slope or a product
      column -- can never sit on both sides, so it can never take this value.'
    in_subset:
    - mvp
    - model_extracted