Inter-Rater Reliability Calculator
Inter-rater reliability (IRR) is a crucial concept in research and data analysis, measuring the extent to which different raters (or observers) agree on their judgments or ratings when assessing the same phenomenon. High IRR indicates that the measurement tool or criteria are clear and consistently applied, leading to more dependable and valid results. Conversely, low IRR suggests ambiguity in the criteria, rater bias, or inadequate training, which can significantly undermine the reliability of the data. This calculator helps you determine IRR using a simple percentage of agreement.
The most straightforward method to calculate inter-rater reliability is by determining the percentage of agreement between two raters. This is calculated by dividing the number of items on which the raters agreed by the total number of items rated, and then multiplying by 100.
Formula:
Inter-Rater Reliability (%) = (Number of Agreements / Total Number of Items) * 100
function calculateIRR() {
var agreementsInput = document.getElementById("agreements");
var totalItemsInput = document.getElementById("totalItems");
var resultDiv = document.getElementById("result");
var agreements = parseFloat(agreementsInput.value);
var totalItems = parseFloat(totalItemsInput.value);
if (isNaN(agreements) || isNaN(totalItems)) {
resultDiv.innerHTML = "Please enter valid numbers for both fields.";
return;
}
if (totalItems <= 0) {
resultDiv.innerHTML = "Total number of items must be greater than zero.";
return;
}
if (agreements < 0 || totalItems totalItems) {
resultDiv.innerHTML = "Number of agreements cannot be greater than the total number of items.";
return;
}
var reliability = (agreements / totalItems) * 100;
resultDiv.innerHTML = "Inter-Rater Reliability:
" + reliability.toFixed(2) + "%";
}
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