Data Visualization and Data Summary - Text Mining Techniques for Healthcare Provider Quality Determination - page 37

Figure 2. Length of stay limited to 50 days maximum
a very heavy tail with the maximum stay of about 354 days. The average length of stay is equal to 5
days with a standard deviation of 5.8 days. Figure 2 reduces the values on the x-axis to a maximum of
50 days so that we can focus on this part of the graph.
In Figure 2, note the gaps that occur because of rounding in the length of stay. It suggests that the
information is not completely accurate because of this rounding.
Figure 3 gives the best normal estimate of the population distribution. It significantly under-values
the probability at the low end, but also does not adequately estimate the outliers, or extreme patient
outcomes.
Figure 4 gives an exponential distribution estimate. It better follows the pattern of the bar graph, but
it still under-values the height of the bars.
Figure 3. Normal estimate of population distribution