Help:RiskModel

The <riskmodel> tag defines a risk model on a wiki page, specifying a calculation and a unique name for use in a RiskDisplay (most likely on another page; best practice is to put the risk model on a /Data subpage along with the data about a risk). Variables in the calculation must match column names in a DataTable2 table. The text inside the tag describes the risk and should include the `{result}` placeholder.

Syntax

The <riskmodel> tag supports these attributes:

`name`: (Required) A unique name for the risk model on the page.
`calculation`: (Required) The mathematical expression defining the model, using variable names that match DataTable2 column names (e.g., `base_probability * distraction_odds_ratio`).

Basic syntax:

<riskmodel name="ModelName" calculation="base_probability * distraction_odds_ratio">Your risk is about {result}%</riskmodel>

Usage

Use the <riskmodel> tag in your wikitext, specifying the `name` and `calculation` attributes.
Ensure variable names in the `calculation` match column names in a DataTable2 table.
Include text between the opening and closing tags to describe the risk, using the `{result}` placeholder to show the calculated value.
Optionally, use wikitext markup or templates like {{One_In_X|{result}}}, which converts fractional probabilities (e.g., 0.1) into text like "1 in 10".
Reference the model by its `name` in other tags, like <riskdisplay>.

The `calculation` defines a mathematical expression using DataTable2 column names, and the text with `{result}` describes the risk outcome for display.

Examples

Basic Risk Model

Define a risk model named "ColdRisk" with a calculation and result description:

<riskmodel name="ColdRisk" calculation="base_probability * exposure_factor">Your risk of catching a cold is about {result}%</riskmodel>

This creates a model called "ColdRisk" that multiplies `base_probability` and `exposure_factor`, displaying the result as a percentage.

Risk Model with Template

Use the `One_In_X` template for human-friendly probability:

<riskmodel name="AccidentRisk" calculation="base_probability * distraction_odds_ratio">Your chance of an accident is {{One_In_X|{result}}}</riskmodel>

This model, "AccidentRisk", computes `base_probability * distraction_odds_ratio` and displays the result as "1 in X" (e.g., "1 in 10" for 0.1).

Risk Model with Complex Calculation

Define a model with a more complex expression and wikitext formatting:

<riskmodel name="RiskScore" calculation="base_probability * severity_weight + mitigation_factor / 2">The weighted risk score is '''{result}''' points</riskmodel>

This model, "RiskScore", computes `base_probability * severity_weight + mitigation_factor / 2`, displaying the result in bold.

Notes

The `name` attribute must be unique on the page to avoid conflicts.
Variable names in the `calculation` must match column names in a DataTable2 table (e.g., `base_probability`, `exposure_factor`). Mismatched names will cause errors.
The `{result}` placeholder must be included in the tag’s text to show the calculated value.
The text inside the tag can include wikitext markup (e.g., `bold`) or templates like `Error: Invalid probability}` for formatting the result.
Risk models can be defined on the current page or a "Data/" subpage and referenced by name in other tags.

Troubleshooting

**Error: "riskmodel: missing name attribute"** – Include the `name` attribute in the tag.
**Error: "riskmodel: missing calculation attribute"** – Include the `calculation` attribute.
**Error: "riskmodel [expression]: [error message]"** – Check the `calculation` for syntax errors (e.g., unbalanced parentheses or invalid operators).
**Model not found in `<riskdisplay>`** – Ensure the `name` matches exactly and the model is defined on the current page or a "Data/" subpage.
**Calculation fails** – Verify that all variable names in the `calculation` match column names in the associated DataTable2 table.
**Result not displayed** – Ensure the `{result}` placeholder is included in the tag’s text and the calculation is valid.

For related features, see RiskDisplay documentation