El rango intercuartílico (IQR) is a statistical measure used to quantify the amount of variation or dispersion in a dataset. Specifically, it represents the range within which the central 50% of the data points lie, effectively providing a way to understand the spread of the data while minimizing the influence of outliers.
Para calcular el IQR, primero, el conjunto de datos se ordena en forma ascendente. Luego, se identifica el primer cuartil (Q1), que es la mediana de la mitad inferior del conjunto de datos, y se encuentra el tercer cuartil (Q3), que es la mediana de la mitad superior. El IQR se calcula restando Q1 de Q3:
IQR = Q3 – Q1
The resulting value gives a clear indication of the variability of the data. A smaller IQR suggests that the data points are closely clustered around the median, while a larger IQR indicates a wider spread of values. This metric is particularly useful in identifying outliers, which are defined as data points that fall below Q1 – 1.5 * IQR or above Q3 + 1.5 * IQR.
En general, el rango intercuartílico es una herramienta esencial en estadísticas descriptivas, allowing researchers and analysts to summarize and interpret data effectively. It is widely used in various fields, including finance, healthcare, and ciencias sociales, to assess distribución de datos and inform decision-making.