Road Accidents - Victoria
Aayush Kapoor
29/09/2019
Introduction
The Road traffic accidents occurred randomly in time and location. This is due to an incident depends on a number of factors such as driver, vehicle, road conditions and weather conditions. These factors may play a role in an incident occurrence separately or jointly. Driving behavior changes in response to the vehicle and road, therefore, it’s complicated to predict where and when traffic accident would happen. Based on historical traffic accident data, it’s possible to analyze traffic incident data to find a relationship between factors. Data analysis and visualization help to observe the traffic accidents occurrence and take appropriate measures to increase traffic safety.
Based on the data collected by enforcement agencies let’s explore the structure of our accident dataset.
Structure of Dataset
## 'data.frame': 54258 obs. of 39 variables:
## $ accident_no : chr "T20060000265" "T20070034197" "T20070035112" "T20070036807" ...
## $ accidentdate : Date, format: "2006-01-20" "2006-12-18" ...
## $ accident.type.desc : Factor w/ 9 levels "Collision with a fixed object",..: 1 3 8 3 4 3 3 3 3 3 ...
## $ day.week.description: Factor w/ 7 levels "Friday","Monday",..: 1 2 5 3 4 2 6 7 7 1 ...
## $ dca.description : Factor w/ 80 levels "ACCIDENT OR BROKEN DOWN ",..: 17 61 2 14 41 38 54 79 60 54 ...
## $ directory : Factor w/ 5 levels ""," ","MEL","VCD",..: 1 3 3 3 5 3 3 3 3 3 ...
## $ light.condition.desc: Factor w/ 7 levels "Dark No street lights",..: 1 5 5 5 5 5 5 5 5 7 ...
## $ node_id : int -10 42318 212616 44601 212038 212575 212767 212769 30042 56757 ...
## $ no_of_vehicles : int 1 2 1 2 1 2 3 2 2 2 ...
## $ no_persons : int 4 2 2 2 1 2 3 2 2 4 ...
## $ no_persons_inj_2 : int 0 0 1 0 0 0 0 0 0 0 ...
## $ no_persons_inj_3 : int 4 1 0 1 1 1 1 1 1 1 ...
## $ no_persons_killed : int 0 0 0 0 0 0 0 0 0 0 ...
## $ no_persons_not_inj : int 0 1 1 1 0 1 2 1 1 3 ...
## $ police_attend : Factor w/ 3 levels "No","Not Known",..: 1 1 3 1 1 1 1 1 1 1 ...
## $ road.geometry.desc : Factor w/ 9 levels "Cross intersection",..: 4 1 4 7 4 4 4 4 7 7 ...
## $ severity : Factor w/ 4 levels "Fatal accident",..: 3 3 4 3 3 3 3 3 3 3 ...
## $ speed_zone : Factor w/ 13 levels "100 km/hr","110 km/hr",..: 1 6 9 12 11 6 9 12 12 9 ...
## $ road_name : Factor w/ 8528 levels " "," ","13 MILE ROAD",..: 1 8111 2567 6467 5934 1856 4474 3813 2721 2322 ...
## $ road_type : Factor w/ 57 levels ""," ","ALLEY",..: 1 43 43 43 51 47 55 43 43 21 ...
## $ road_name_int : Factor w/ 12651 levels ""," ","1 IN 10",..: 1 2185 438 4692 8172 10339 3150 2177 180 9235 ...
## $ road_type_int : Factor w/ 89 levels ""," ","ACCESS",..: 1 75 68 75 68 6 75 68 68 43 ...
## $ distance_location : int NA 0 10 0 1816 7 57 44 0 0 ...
## $ direction_location : Factor w/ 11 levels ""," ","E","N",..: 1 8 4 8 5 11 7 11 8 5 ...
## $ node_type : Factor w/ 4 levels " ","Intersection",..: NA 2 3 2 3 3 3 3 2 2 ...
## $ lga_name : Factor w/ 210 levels "(FALLS CREEK)",..: NA 65 187 34 13 32 87 32 174 26 ...
## $ lga.name.all : chr NA "KINGSTON,GLEN EIRA" "WYNDHAM" "DAREBIN" ...
## $ region.name : Factor w/ 8 levels " ","EASTERN REGION",..: NA 4 3 3 2 4 3 4 4 4 ...
## $ deg.urban.name : Factor w/ 7 levels "LARGE PROVINCIAL CITIES",..: NA 2 4 2 4 2 2 2 2 2 ...
## $ lat : num NA -37.9 -37.9 -37.7 -37.8 ...
## $ long : num NA 145 145 145 146 ...
## $ postcode.no : int NA 3167 3030 3083 3833 3175 3006 3172 3129 3803 ...
## $ mday : int 20 18 14 20 12 13 21 18 1 1 ...
## $ month : num 1 12 12 5 11 11 11 10 2 9 ...
## $ accyear : num 2016 2016 2016 2016 2016 ...
## $ hour : int 22 19 15 10 15 8 9 10 10 12 ...
## $ minute : int 10 30 55 0 0 45 45 0 0 30 ...
## $ week.end.night : chr "Yes" "No" "No" "No" ...
## $ road_route_desc : Factor w/ 6 levels "Forest Roads",..: NA 2 3 2 6 6 2 3 3 6 ...The dataset contain a total of 54258 rows and 39 columns. Each row represents an accident that took place in Victoria region. The dataset contains nine records of accidents that occured in 2006 and one record for 2036 that is considered as data entry error, the value is updated to 2016 as one of the steps of data wrangling and outlier detection. Out of 39 columns, we will be considering ten categorical and six numerical variables including the date, month and year variables to check for seasonality or any trend.
- Time Series Variables
- Year
- Month
- Day of Week
- Categorical variables
- Light Conditions (7 factors)
- Accident Type (9 factors)
- Police at Scene (3 factors)
- Road Geometry (9 factors)
- Severity (3 factors)
- Node Type (4 factors)
- Weekend Night (2 factors)
- Road Route (7 factors)
- Continous variables
- No of Vehicles Involved
- No of Person Involved
- No of Person with Injury Level 2
- No of Person with Injury Level 3
- No of Person Killed
- No of Person Not Injured
Time-Series and Categorical Variables
Year
- Let’s create some aggregate tables to understand the Year variable better
- From the data tables the number of accidents have reduced from 2016 to 2017 by 21%, no of person killed reduced by 17% and no of vehicles involved reduced by 21%.
- The highest number of accidents were recorded in 2015
| Year | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| 2014 | 14249 | 25590 | 34060 | 248 |
| 2015 | 14417 | 26024 | 34381 | 252 |
| 2016 | 14304 | 25809 | 33822 | 290 |
| 2017 | 11288 | 20445 | 27166 | 241 |
| Year | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| 2014 | 5131 | 12569 | 16110 |
| 2015 | 4790 | 13005 | 16318 |
| 2016 | 4670 | 13087 | 15773 |
| 2017 | 3295 | 10906 | 12719 |
Day of the Week
- Most number of accidents happened on Friday that sums to around 8600 accidents accounting for total of 172 deaths during 2014-2017 in Victoria.
| Days | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| Friday | 8527 | 15697 | 20614 | 172 |
| Monday | 7366 | 13295 | 17305 | 143 |
| Saturday | 7610 | 12887 | 18498 | 158 |
| Sunday | 6873 | 11410 | 16346 | 150 |
| Thursday | 8112 | 15078 | 19132 | 136 |
| Tuesday | 7703 | 14345 | 18203 | 122 |
| Wednesday | 8067 | 15156 | 19331 | 150 |
| Days | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| Friday | 2709 | 7794 | 9934 |
| Monday | 2325 | 6778 | 8057 |
| Saturday | 2905 | 6917 | 8524 |
| Sunday | 2703 | 6083 | 7402 |
| Thursday | 2476 | 7418 | 9100 |
| Tuesday | 2300 | 7132 | 8642 |
| Wednesday | 2468 | 7445 | 9261 |
Month
- The month of march recorded most accidents where the number of vehicles involved and number of person involved are also highest 9265 and 12152 respectively.
| Month | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| 1 | 4306 | 7454 | 10089 | 87 |
| 2 | 4613 | 8468 | 10980 | 92 |
| 3 | 5143 | 9265 | 12152 | 94 |
| 4 | 4665 | 8359 | 11073 | 80 |
| 5 | 4877 | 8890 | 11724 | 89 |
| 6 | 4297 | 7772 | 10283 | 77 |
| 7 | 4358 | 7917 | 10504 | 87 |
| 8 | 4308 | 7786 | 10217 | 100 |
| 9 | 3934 | 7134 | 9403 | 67 |
| 10 | 4675 | 8475 | 11239 | 79 |
| 11 | 4563 | 8239 | 10860 | 98 |
| 12 | 4519 | 8109 | 10905 | 81 |
| Month | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| 1 | 1507 | 3944 | 4551 |
| 2 | 1506 | 4218 | 5162 |
| 3 | 1680 | 4687 | 5690 |
| 4 | 1597 | 4208 | 5183 |
| 5 | 1514 | 4477 | 5642 |
| 6 | 1352 | 3923 | 4933 |
| 7 | 1350 | 4037 | 5029 |
| 8 | 1327 | 3970 | 4817 |
| 9 | 1204 | 3649 | 4481 |
| 10 | 1626 | 4179 | 5350 |
| 11 | 1572 | 4163 | 5022 |
| 12 | 1651 | 4112 | 5060 |
Light Condition
- The light condition or level of brightness at the time of the accident
- Most accidents have happened in Day light as oppose to dark or no light conditions staggering to a total of 34663 accidents involving 63802 vehicles and 84533 person consuming 576 lives.
| Light Conditions | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| Dark No street lights | 2932 | 3873 | 5534 | 186 |
| Dark Street lights off | 111 | 191 | 251 | 6 |
| Dark Street lights on | 8217 | 14776 | 20045 | 153 |
| Dark Street lights unknown | 555 | 904 | 1126 | 8 |
| Day | 34633 | 63802 | 84553 | 576 |
| Dusk/Dawn | 6488 | 11946 | 15113 | 93 |
| Unknown | 1322 | 2376 | 2807 | 9 |
| Light Conditions | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| Dark No street lights | 1435 | 2230 | 1681 |
| Dark Street lights off | 40 | 98 | 107 |
| Dark Street lights on | 3035 | 7295 | 9559 |
| Dark Street lights unknown | 142 | 476 | 500 |
| Day | 10932 | 32464 | 40562 |
| Dusk/Dawn | 2092 | 5801 | 7126 |
| Unknown | 210 | 1203 | 1385 |
ACCIDENT.TYPE
- Description of what occurred, based on nine categories.
- Collision is most cause among car crashes, that might happen due various conditions like light condition, road geometry (sight hinderance/ blind sight), repeated collision spots should be taken into consideration to improve the chances of crash.
| Accident Type | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| Collision with a fixed object | 8568 | 9117 | 12756 | 360 |
| collision with some other object | 493 | 595 | 722 | 5 |
| Collision with vehicle | 34160 | 76100 | 96656 | 470 |
| Fall from or in moving vehicle | 247 | 257 | 605 | 3 |
| No collision and no object struck | 2794 | 3287 | 3620 | 11 |
| Other accident | 40 | 46 | 68 | 1 |
| Struck animal | 565 | 617 | 783 | 8 |
| Struck Pedestrian | 4634 | 4842 | 10385 | 137 |
| Vehicle overturned (no collision) | 2757 | 3007 | 3834 | 36 |
| Accident Type | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| Collision with a fixed object | 4058 | 6107 | 2230 |
| collision with some other object | 161 | 373 | 183 |
| Collision with vehicle | 9338 | 35516 | 51315 |
| Fall from or in moving vehicle | 135 | 127 | 340 |
| No collision and no object struck | 999 | 1884 | 724 |
| Other accident | 16 | 25 | 26 |
| Struck animal | 202 | 431 | 142 |
| Struck Pedestrian | 1878 | 3019 | 5350 |
| Vehicle overturned (no collision) | 1099 | 2085 | 610 |
POLICE.ATTEND
- Whether or not the police attended the scene of the accident.
- For more than 14000 accidents the police was not at the accident scene.
| Police at the scene of Accident | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| No | 14014 | 24354 | 28617 | 6 |
| Not Known | 217 | 397 | 469 | 1 |
| Yes | 40027 | 73117 | 100343 | 1024 |
| Police at the scene of Accident | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| No | 2253 | 12940 | 13404 |
| Not Known | 66 | 169 | 233 |
| Yes | 15567 | 36458 | 47283 |
ROAD.GEOMETRY
- The layout of the road where the accident occurred.
| Road Layout | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| Cross intersection | 11893 | 22886 | 31478 | 139 |
| Dead end | 65 | 89 | 113 | 1 |
| Multiple intersection | 1259 | 2434 | 3264 | 10 |
| Not at intersection | 28276 | 48342 | 62730 | 736 |
| Private property | 2 | 4 | 3 | 0 |
| Road closure | 3 | 3 | 4 | 0 |
| T intersection | 12601 | 23840 | 31501 | 144 |
| Unknown | 73 | 117 | 147 | 1 |
| Y intersection | 86 | 153 | 189 | 0 |
| Road Layout | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| Cross intersection | 3188 | 12123 | 16018 |
| Dead end | 31 | 48 | 33 |
| Multiple intersection | 357 | 1261 | 1635 |
| Not at intersection | 10550 | 23946 | 27491 |
| Private property | 1 | 1 | 1 |
| Road closure | 1 | 2 | 1 |
| T intersection | 3706 | 12044 | 15600 |
| Unknown | 22 | 63 | 61 |
| Y intersection | 30 | 79 | 80 |
SEVERITY
- VicRoads estimation of the severity or seriousness of the accident
| Accident Severity | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| Fatal accident | 952 | 1568 | 2456 | 1031 |
| Non injury accident | 2 | 4 | 8 | 0 |
| Other injury accident | 37947 | 70797 | 91972 | 0 |
| Serious injury accident | 15357 | 25499 | 34993 | 0 |
| Accident Severity | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| Fatal accident | 468 | 251 | 704 |
| Non injury accident | 0 | 0 | 8 |
| Other injury accident | 8 | 46113 | 45831 |
| Serious injury accident | 17410 | 3203 | 14377 |
SPEED_ZONE
- the speed zone at the location of the accident. The speed zone is generally assigned to the main vehicle involved
| Speed Limit | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| 100 km/hr | 8290 | 13032 | 18319 | 483 |
| 110 km/hr | 590 | 853 | 1375 | 38 |
| 30 km/hr | 83 | 126 | 157 | 0 |
| 40 km/hr | 3045 | 5344 | 7056 | 16 |
| 50 km/hr | 8986 | 15390 | 19677 | 79 |
| 60 km/hr | 18141 | 34775 | 45485 | 182 |
| 70 km/hr | 3607 | 7331 | 9671 | 65 |
| 75 km/hr | 8 | 13 | 14 | 1 |
| 80 km/hr | 7631 | 14834 | 20224 | 148 |
| 90 km/hr | 188 | 366 | 537 | 9 |
| Camping Grounds or off road | 371 | 461 | 559 | 2 |
| Not Known | 3249 | 5240 | 6216 | 7 |
| Other speed limit | 69 | 103 | 139 | 1 |
| Speed Limit | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| 100 km/hr | 4112 | 6954 | 6772 |
| 110 km/hr | 321 | 502 | 514 |
| 30 km/hr | 23 | 67 | 67 |
| 40 km/hr | 783 | 2665 | 3587 |
| 50 km/hr | 2575 | 7888 | 9137 |
| 60 km/hr | 5148 | 17274 | 22872 |
| 70 km/hr | 1107 | 3536 | 4961 |
| 75 km/hr | 3 | 4 | 6 |
| 80 km/hr | 2781 | 7424 | 9865 |
| 90 km/hr | 87 | 210 | 228 |
| Camping Grounds or off road | 115 | 276 | 166 |
| Not Known | 812 | 2711 | 2682 |
| Other speed limit | 19 | 56 | 63 |
NODE_TYPE
- location type identified by the RCIS spatial system
| Location type | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| 20 | 32 | 47 | 0 | |
| Intersection | 24741 | 47336 | 63919 | 274 |
| Non-Intersection | 29328 | 50252 | 65147 | 756 |
| Off Road | 155 | 228 | 288 | 1 |
| NA | 14 | 20 | 28 | 0 |
| Location type | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| 4 | 20 | 23 | |
| Intersection | 6952 | 24518 | 32156 |
| Non-Intersection | 10874 | 24891 | 28620 |
| Off Road | 55 | 120 | 112 |
| NA | 1 | 18 | 9 |
WEEKEND.NIGHT
- binary variable with yes or no
- weekend night starts at 10 PM Friday and ends at 6 AM Sunday
| Was Weekend Night? | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| No | 51680 | 94007 | 123821 | 931 |
| Yes | 2578 | 3861 | 5608 | 100 |
| Weekend Night | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| No | 16696 | 47466 | 58704 |
| Yes | 1190 | 2101 | 2216 |
ROAD.ROUTE
- This is the primary road/route number for road_name_1
- Group Classifications are: 2000-2999 Freeways or Highways 3000-3999 Forest Rds 4000-4999 Tourist Rds 5000-5999 Main Rds 7000-7999 Ramps (mainly Freeway ramps) 9999 Unclassified Roads e.g. Council / ?Local? roads
| Road Classification | No. of Accidents | No of Vehicles Involved | No of Person Involved | Killed |
|---|---|---|---|---|
| Forest Roads | 22 | 27 | 33 | 1 |
| Freeways or Highways | 11858 | 23553 | 31917 | 280 |
| Main Roads | 18119 | 34173 | 45222 | 336 |
| Ramps(mainly Freeway ramps) | 664 | 1250 | 1613 | 6 |
| Tourist Roads | 768 | 1156 | 1819 | 26 |
| Unclassified Roads | 18229 | 29761 | 38521 | 284 |
| NA | 4598 | 7948 | 10304 | 98 |
| Road Classification | No of Person with Injury of Level 2 | No of Person with Injury of Level 3 | Not Injured |
|---|---|---|---|
| Forest Roads | 10 | 15 | 6 |
| Freeways or Highways | 4121 | 11434 | 16066 |
| Main Roads | 5606 | 17098 | 22175 |
| Ramps(mainly Freeway ramps) | 194 | 647 | 766 |
| Tourist Roads | 321 | 730 | 747 |
| Unclassified Roads | 6137 | 15528 | 16563 |
| NA | 1497 | 4115 | 4597 |
Continous Variables
## accident_no accidentdate
## Length:54258 Min. :2006-01-20
## Class :character 1st Qu.:2014-12-13
## Mode :character Median :2015-11-26
## Mean :2015-11-28
## 3rd Qu.:2016-11-01
## Max. :2036-11-13
##
## accident.type.desc day.week.description
## Collision with vehicle :34160 Friday :8527
## Collision with a fixed object : 8568 Monday :7366
## Struck Pedestrian : 4634 Saturday :7610
## No collision and no object struck: 2794 Sunday :6873
## Vehicle overturned (no collision): 2757 Thursday :8112
## Struck animal : 565 Tuesday :7703
## (Other) : 780 Wednesday:8067
## dca.description
## REAR END(VEHICLES IN SAME LANE) : 9783
## RIGHT THROUGH : 4756
## CROSS TRAFFIC(INTERSECTIONS ONLY) : 3624
## LEFT OFF CARRIAGEWAY INTO OBJECT/PARKED VEHICLE : 3042
## RIGHT NEAR (INTERSECTIONS ONLY) : 2512
## OUT OF CONTROL ON CARRIAGEWAY (ON STRAIGHT) : 2470
## (Other) :28071
## directory light.condition.desc node_id
## : 27 Dark No street lights : 2932 Min. : -10
## : 4268 Dark Street lights off : 111 1st Qu.: 46502
## MEL:37557 Dark Street lights on : 8217 Median :277363
## VCD: 7 Dark Street lights unknown: 555 Mean :202217
## VCS:12399 Day :34633 3rd Qu.:302237
## Dusk/Dawn : 6488 Max. :327712
## Unknown : 1322
## no_of_vehicles no_persons no_persons_inj_2 no_persons_inj_3
## Min. : 1.000 Min. : 1.000 Min. : 0.0000 Min. : 0.0000
## 1st Qu.: 1.000 1st Qu.: 2.000 1st Qu.: 0.0000 1st Qu.: 0.0000
## Median : 2.000 Median : 2.000 Median : 0.0000 Median : 1.0000
## Mean : 1.804 Mean : 2.385 Mean : 0.3296 Mean : 0.9135
## 3rd Qu.: 2.000 3rd Qu.: 3.000 3rd Qu.: 1.0000 3rd Qu.: 1.0000
## Max. :14.000 Max. :89.000 Max. :16.0000 Max. :25.0000
##
## no_persons_killed no_persons_not_inj police_attend
## Min. :0.000 Min. : 0.000 No :14014
## 1st Qu.:0.000 1st Qu.: 0.000 Not Known: 217
## Median :0.000 Median : 1.000 Yes :40027
## Mean :0.019 Mean : 1.123
## 3rd Qu.:0.000 3rd Qu.: 1.000
## Max. :4.000 Max. :87.000
##
## road.geometry.desc severity
## Not at intersection :28276 Fatal accident : 952
## T intersection :12601 Non injury accident : 2
## Cross intersection :11893 Other injury accident :37947
## Multiple intersection: 1259 Serious injury accident:15357
## Y intersection : 86
## Unknown : 73
## (Other) : 70
## speed_zone road_name road_type
## 60 km/hr :18141 : 4266 ROAD :25138
## 50 km/hr : 8986 PRINCES HIGHWAY : 880 STREET :11496
## 100 km/hr: 8290 HIGH STREET : 783 HIGHWAY: 4642
## 80 km/hr : 7631 NEPEAN HIGHWAY : 524 : 4266
## 70 km/hr : 3607 SPRINGVALE ROAD : 415 FREEWAY: 1879
## Not Known: 3249 SOUTH GIPPSLAND HIGHWAY: 390 AVENUE : 1294
## (Other) : 4354 (Other) :47000 (Other): 5543
## road_name_int road_type_int distance_location direction_location
## VICTORIA : 316 ROAD :19972 Min. : -1.0 W :12079
## HIGH : 312 STREET :16829 1st Qu.: 0.0 S : 9760
## STATION : 306 AVENUE : 2847 Median : 16.0 N : 9130
## PRINCES : 301 DRIVE : 2745 Mean : 145.9 E : 7803
## : 247 RAMP : 2279 3rd Qu.: 93.0 NW : 4471
## WELLINGTON: 216 LANE : 1443 Max. :14785.0 SE : 3757
## (Other) :52560 (Other): 8143 NA's :14 (Other): 7258
## node_type lga_name lga.name.all
## : 20 MELBOURNE: 2609 Length:54258
## Intersection :24741 CASEY : 2143 Class :character
## Non-Intersection:29328 GEELONG : 1966 Mode :character
## Off Road : 155 DANDENONG: 1701
## NA's : 14 HUME : 1697
## (Other) :44128
## NA's : 14
## region.name deg.urban.name
## METROPOLITAN SOUTH EAST REGION:19341 MELB URBAN :34075
## METROPOLITAN NORTH WEST REGION:19144 RURAL VICTORIA :11724
## SOUTH WESTERN REGION : 3919 LARGE PROVINCIAL CITIES: 3040
## NORTHERN REGION : 3060 SMALL CITIES : 2657
## EASTERN REGION : 3031 TOWNS : 1576
## (Other) : 5749 (Other) : 1172
## NA's : 14 NA's : 14
## lat long postcode.no mday
## Min. :-39.02 Min. :141.0 Min. :3000 Min. : 1.0
## 1st Qu.:-37.95 1st Qu.:144.9 1st Qu.:3074 1st Qu.: 8.0
## Median :-37.82 Median :145.0 Median :3177 Median :16.0
## Mean :-37.71 Mean :145.0 Mean :3313 Mean :15.7
## 3rd Qu.:-37.70 3rd Qu.:145.2 3rd Qu.:3550 3rd Qu.:23.0
## Max. :-34.13 Max. :149.8 Max. :3996 Max. :31.0
## NA's :14 NA's :14 NA's :14
## month accyear hour minute
## Min. : 1.000 Min. :2014 Min. : 0.00 Min. : 0.0
## 1st Qu.: 3.000 1st Qu.:2014 1st Qu.: 9.00 1st Qu.:10.0
## Median : 6.000 Median :2015 Median :14.00 Median :28.0
## Mean : 6.438 Mean :2015 Mean :13.23 Mean :24.9
## 3rd Qu.:10.000 3rd Qu.:2016 3rd Qu.:17.00 3rd Qu.:40.0
## Max. :12.000 Max. :2017 Max. :23.00 Max. :59.0
##
## week.end.night road_route_desc
## Length:54258 Forest Roads : 22
## Class :character Freeways or Highways :11858
## Mode :character Main Roads :18119
## Ramps(mainly Freeway ramps): 664
## Tourist Roads : 768
## Unclassified Roads :18229
## NA's : 4598Problem Definition
Using the categorical variable - Accident Severity, let’s can try exploring the dataset by answering the following questions and then providing either statistical analysis or visualization to conclude the findings. For the chi-square test for independence, we have
- Null Hypothesis - Accident Severity is independent of X1
- Alternative Hypothesis - Accident Severity is not independent of X1
- X1 is random variable observed in the given dataset (other categorical variables)
1. Crashes on weekend nights more prone to serious/fatal injury?
Accident Severity vs Weekend Night
- From the given chart, we can see that there is significantly a large proportion of serious crashes have happened on weekend night. Also,
- The chi-square test for independence gives the p-value is less than 0.05, so we can reject the null hypothesis that Accident Severity is not related to weekend night.
##
## Pearson's Chi-squared test
##
## data: .
## X-squared = 209.06, df = 18, p-value < 2.2e-16
2. The difference in Accident Severity is related to light conditions ?
Accident Severity and Light Conditions
- From the graph, the plausible reason of Fatal and Serious accidents, were light conditions on the day of crash. For most fatal and serious injury accident Dark w/o Street lights was cited as the most common reason.
- The chi-square test for independence gives the p-value is less than 0.05, so we can reject the null hypothesis that Accident Severity is independent of light conditions.
##
## Pearson's Chi-squared test
##
## data: .
## X-squared = 713.71, df = 18, p-value < 2.2e-16
3. Is accident severity related to the layout of road layout ?
Accident Severity and Road Geometry
- Road Geometry is one of the most important factor in deciding the fate of pessengers involved in crash. From the given chart the number of accidents are more common on cross-intersection, multiple-intersection. The chances of fatal accidents happening on intersection is low (due to reduced speed) as compared to a non-intersection crash.
- The chi-square test for independence gives the p-value is less than 0.05, so we can reject the null hypothesis that Accident Severity is independent of road layout.
##
## Pearson's Chi-squared test
##
## data: .
## X-squared = 615.65, df = 24, p-value < 2.2e-16
4. Accident severity depends on Speed limit ?
Accident Severity and Speed Limit
- High speed zones may lead to more sever crashes. Based on the graph, for a driver travelling at speed of 100 km/hr or higher is more prone to serious injury accidents.
- The average response time for human to avoid a hazzard is about 1.9 seconds, travelling at the speed higher than 90 Km/hr needs an average distance of 110 meters and 4 seconds to stop.
- The chi-square test for independence gives the p-value is less than 0.05, so we can reject the null hypothesis that Accident Severity is independent of Speed limit.
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## Pearson's Chi-squared test
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## data: .
## X-squared = 1521.6, df = 36, p-value < 2.2e-16
##### 5. Does the Accident severity differs in different Rural/Urban areas?
Accident Severity vs Urban/Rural Area
- The chances of fatal or serious accidents are more in Rural area. The plausible reason could be unavailablity of proper infrastructure(street lights, road conditions, animal fencing, warning signs) that can significantly reduce the impact of crashes in Rural areas.
- The chi-square test for independence gives the p-value is less than 0.05, so we can reject the null hypothesis that Accident Severity is independent of Rural/Urban areas.
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## Pearson's Chi-squared test
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## data: .
## X-squared = 1519.9, df = 18, p-value < 2.2e-16
Recommendations
- Improvement of road designs that includes divided and undivided road, sight distance, safety barriers, bridge or overtaking.
- Proper traffic management, traffic engineering, road construction and maintenance and regulation of speed limits.
- Improvement of early warnings sign for dark/no light and common accident prone spots.
- Avoiding risk like Speeding, Drink-Driving, Distracted driving.
- Utilizing more advanced road engineering and traffic management strategies