Help:RiskModel

The <riskmodel> tag defines a risk model on a wiki page, specifying 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) and text that is displayed to the user after they select any risk parameters.

Syntax

The <riskmodel> tag supports these attributes:

`name`: (Required) A unique name for the risk model on the page.

Basic syntax:

<riskmodel name="ModelName">Your risk is about {{#expr: {base_probability} * {distraction_odds_ratio} }}%</riskmodel>

Usage

Include text between the opening and closing tags to describe the risk, using the `{variable}` placeholder to show user-selected values (`variable` will be a column name from a DropDown).
Use the extension to compute a risk score from user-selected values
Optionally, use templates like {{One_In_X|...}}, 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.

Magic placeholders

The following placeholders in the text between the opening and closing riskmodel tags are replaced before any templates or other WikiText are processed:

{pagestate} : all of the key/value pairs from DropDown or RiskParameter as a single string in the format: key1=value1|key2=value2|...etc. This is so you can easily pass the page state to templates. For example, {{SomeFancyTemplate|result={result}|{pagestate}}} might have logic to display "The risk of 58-year-old male who eats a poppy-seed bagel four times a week of failing a drug test is about ..."
{variable} where variable is any of the values set by a DropDown or RiskParameter

Examples

Basic Risk Model

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

<riskmodel name="ColdRisk">Your risk of catching a cold is about {{#expr: {base_probability}*{exposure_factor} }}%</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|{{#expr: {base_probability}*{distraction_odds_ration} }} }}</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">The weighted risk score is '''{{#expr: {base_probability} * {severity_weight} + {mitigation_factor} / 2}}''' 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 RiskData table (e.g., `base_probability`, `exposure_factor`). Mismatched names will cause errors.
The text inside the tag can include wikitext markup (e.g., `bold`) or templates like `Error: Invalid probability {result}` 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.
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 RiskData 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