Fig. 6: Classification of myocardial infarction cases (n = 1340) into four clusters based on the sum of the Kp index (y-axis) and the K-means algorithm, with sex and age as additional attributes.
From: Influence of geomagnetic disturbances on myocardial infarctions in women and men from Brazil
Each point represents a myocardial infarction (MI) hospitalization case, marked in red for females and blue for males. Cluster 1: Exclusively composed of females under quiet geomagnetic conditions. Cluster 2: Male predominance under moderate geomagnetic activity, with both sexes present. Cluster 3: Higher geomagnetic activity intensity (disturbed) with female predominance. Cluster 4: Exclusively composed of males under quiet geomagnetic conditions. The overlapping Kp ranges between some clusters demonstrate the influence of additional variables (such as age) in cluster formation.
