Record vs Normal Spread Z Checker
Record deviation/independent matched normal SD; not tail probability for maxima or normality assumption. Caller independently establishes matching units, evidence, method edition and applicability; output is not compliance, diagnosis, work-safety approval, geological identity or validated hazard prediction.
Description
A standardized anomaly expresses an observation's departure from a reference mean in units of reference standard deviation.
A standardized anomaly expresses an observation's departure from a reference mean in units of reference standard deviation.1
Comparing records requires matching the variable, period and measurement method.
When to use Record vs Normal Spread Z Checker
Use this tool to calculate or review the supplied observations under the stated rules. Establish the observation method, units, averaging period and applicable reference or calibration.
How to use Record vs Normal Spread Z Checker and understand its results
- Establish the observation method, units, averaging period and applicable reference or calibration.
- Enter observedRecordValue, callerMatchedNormalMean, callerMatchedNormalSD, using the field meanings and rules below, then run the tool.
- Read signedRecordZ, using the output meanings and calculation rules below.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedRecordValue | Observed record value | number | Required |
| callerMatchedNormalMean | Caller matched normal mean | number | Required |
| callerMatchedNormalSD | Caller matched normal s d | number | Required |
Use finite observed and reference-mean values and a strictly positive reference standard deviation, all on the same measurement basis. Subtract the mean from the observation and divide by that standard deviation; retain the sign.
z=(observed−referenceMean)/referenceSD Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| signedRecordZ | Signed record z; preserve the subtraction order and sign defined in the mechanics | number |
{
"input": {
"observedRecordValue": 15,
"callerMatchedNormalMean": 10,
"callerMatchedNormalSD": 2
},
"output": {
"signedRecordZ": 2.5
}
}Limitations and assumptions
No normal-distribution assumption is tested and no tail probability, return period or record significance is calculated.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite.
Alternative or Complementary methods
For a related step, use Climate Normals Anomaly Deviation Calculator: A climate anomaly is the difference between an observation and a matched normal. For a complementary comparison, use Koppen Climate Classification Code Lookup: Köppen codes summarize climates under a specified classification scheme.
References
-
Record vs Normal Spread Z Checker — tool.io
Similar or alternative tools
- Climate Normals Anomaly Deviation Calculator
A climate anomaly is the difference between an observation and a matched normal.
- Koppen Climate Classification Code Lookup
Köppen codes summarize climates under a specified classification scheme.