Histogram of astrocytes hypertrophy scores in different ROIs for the various groups. The distribution and the total number is changing in the cortical regions, whereas only the distribution of score is changing in the hippocampus
Cumulative distribution function of astrocytes hypertrophy scores in different ROIs for the various groups. This figure shows the fraction of cells with a hypertrophy score less than the x-axis values. For example, in the hippocampus, about 80% of the cells have a score less than 10 in the 9 and 12 month groups. The cumulative distribution function shows how the distribution of score changes independently of the number of astrocytes.
To obtain a finer-grained picture of the changes at the cellular level between the groups, we can plot the distribution of morphological scores. The histograms of astrocyte morphological scores show region-dependent changes in their distribution. For example, while the cortical regions show a change in the distribution of scores and a large increase in the number of GFAP-positive astrocytes over time, their numbers in the hippocampus are approximately constant.
The change in the distribution of scores can be better observed by plotting the cumulative distribution function (CDF), which shows the fraction of cells with a score less than the x-axis values. For example, in the hippocampus at 6 months, the change in the distribution occurs primarily in the scores greater than 10, while at older ages, the whole distribution shifts to higher scores.