Clustering Analysis

Final Results Scope Results I-210, EB and WB, postmile 25 - 36 AM peak (5 - 10 am) and PM peak (3 - 8 pm) January to May, 2014 (151 days) Results Cluster Type WB AM # of days WB PM EB AM EB PM Weekend/Holiday 50 Weekday Regular 58 55 78 44 Incident * 38 41 19 53 Others 5 4 Total 151 * There are many other types of clusters: events, weather, etc. This analysis focuses on incidents for now.

Illustration The table shows the final result of the clustering analysis for I-210. The scope of the analysis is both directions of I-210 (within our corridor from postmile 25 to 36), both AM peak (5-10am) and PM peak (3-8pm). The 151 days from January 2014 to May 2014 are grouped into four clusters: weekend/holiday, regular, incident, and others (typically lack of data). Note that the clustering is different depending on the direction (WB/EB) and time (AM/PM).

Flow & speed vs. CHP (210WB, AM) PeMS CHP Total Non-incident Incident W’nd/H’day PeMS flow & speed Regular 58 24 82 9 4 13 Others 5 1 6 50 72 29 151 Type Number of days Weekend/Holiday 50 Weekday Regular 58 Incident 38 Others 5

Flow & speed vs. CHP (210WB, PM) PeMS CHP Total Non-incident Incident W’nd/H’day PeMS flow & speed Regular 55 26 81 3 9 12 Others 5 8 50 63 38 151 Type Number of days Weekend/Holiday 50 Weekday Regular 55 Incident 41 Others 5

Flow & speed vs. CHP (210EB, AM) PeMS CHP Total Non-incident Incident W’nd/H’day PeMS flow & speed Regular 78 9 87 5 4 Others 1 50 14 151 Type Number of days Weekend/Holiday 50 Weekday Regular 78 Incident 19 Others 4

Flow & speed vs. CHP (210EB, PM) PeMS CHP Total Non-incident Incident W’nd/H’day PeMS flow & speed Regular 44 27 71 8 13 21 Others 4 5 9 50 56 45 151 Type Number of days Weekend/Holiday 50 Weekday Regular 44 Incident 53 Others 4

Incident Frequency (# of incidents per day reported by CHP among incident days) These graphs show the incident frequency (in incident per day) on the dates clustered as “incident days”. Note that incidents refer to those reported by CHP through PeMS. So 0 incidents per day means we have evidence that incidents occur on these days, but CHP did not report anything. Note that the dominant situation for each direction (WB/EB) and time (AM/PM) is when there is only 1 incident per day.

Incident Severity (all incidents) The graph here shows the joint distribution of closure duration (in minutes) and number of mainline lanes closed. When the number of mainline lanes closed is 0, this means closure occurs on the ramp. Note that the most dominant situation is when 1 lane is closed for around 30 minutes. * Number of mainline lanes closed = 0 means lane closure occurs on the ramp

Incident Severity (WB incidents) * Number of mainline lanes closed = 0 means lane closure occurs on the ramp

Incident Severity (EB incidents) * Number of mainline lanes closed = 0 means lane closure occurs on the ramp