SYPNOSIS

Storms and other severe weather events can cause both public health and economic problems for communities and municipalities. Many severe events can result in fatalities, injuries, and property damage, and preventing such outcomes to the extent possible is a key concern.

The purpose of this analysis is to identify what types of weather events in the United States are most harmful to population health, what types have the greatest economic consequences and some other characteristics that help to be proactive and mitigate public health and economic problems for communities and municipalities.

DATA PROCESSING

#download the file
download.file("https://d396qusza40orc.cloudfront.net/repdata%2Fdata%2FStormData.csv.bz2","Data/repdata%2Fdata%2FStormData.csv.bz2")

#create a variable with the csv.bz2 file previously downloaded
weatherData <- read.csv("Data/repdata%2Fdata%2FStormData.csv.bz2")
#return the type of object
class(weatherData)
## [1] "data.frame"
#display the internal structure of the weatherData object
str(weatherData)
## 'data.frame':    902297 obs. of  37 variables:
##  $ STATE__   : num  1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_DATE  : Factor w/ 16335 levels "1/1/1966 0:00:00",..: 6523 6523 4242 11116 2224 2224 2260 383 3980 3980 ...
##  $ BGN_TIME  : Factor w/ 3608 levels "00:00:00 AM",..: 272 287 2705 1683 2584 3186 242 1683 3186 3186 ...
##  $ TIME_ZONE : Factor w/ 22 levels "ADT","AKS","AST",..: 7 7 7 7 7 7 7 7 7 7 ...
##  $ COUNTY    : num  97 3 57 89 43 77 9 123 125 57 ...
##  $ COUNTYNAME: Factor w/ 29601 levels "","5NM E OF MACKINAC BRIDGE TO PRESQUE ISLE LT MI",..: 13513 1873 4598 10592 4372 10094 1973 23873 24418 4598 ...
##  $ STATE     : Factor w/ 72 levels "AK","AL","AM",..: 2 2 2 2 2 2 2 2 2 2 ...
##  $ EVTYPE    : Factor w/ 985 levels "   HIGH SURF ADVISORY",..: 834 834 834 834 834 834 834 834 834 834 ...
##  $ BGN_RANGE : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ BGN_AZI   : Factor w/ 35 levels "","  N"," NW",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_LOCATI: Factor w/ 54429 levels "","- 1 N Albion",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_DATE  : Factor w/ 6663 levels "","1/1/1993 0:00:00",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_TIME  : Factor w/ 3647 levels ""," 0900CST",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ COUNTY_END: num  0 0 0 0 0 0 0 0 0 0 ...
##  $ COUNTYENDN: logi  NA NA NA NA NA NA ...
##  $ END_RANGE : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ END_AZI   : Factor w/ 24 levels "","E","ENE","ESE",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_LOCATI: Factor w/ 34506 levels "","- .5 NNW",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ LENGTH    : num  14 2 0.1 0 0 1.5 1.5 0 3.3 2.3 ...
##  $ WIDTH     : num  100 150 123 100 150 177 33 33 100 100 ...
##  $ F         : int  3 2 2 2 2 2 2 1 3 3 ...
##  $ MAG       : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ FATALITIES: num  0 0 0 0 0 0 0 0 1 0 ...
##  $ INJURIES  : num  15 0 2 2 2 6 1 0 14 0 ...
##  $ PROPDMG   : num  25 2.5 25 2.5 2.5 2.5 2.5 2.5 25 25 ...
##  $ PROPDMGEXP: Factor w/ 19 levels "","-","?","+",..: 17 17 17 17 17 17 17 17 17 17 ...
##  $ CROPDMG   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ CROPDMGEXP: Factor w/ 9 levels "","?","0","2",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ WFO       : Factor w/ 542 levels ""," CI","$AC",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ STATEOFFIC: Factor w/ 250 levels "","ALABAMA, Central",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ ZONENAMES : Factor w/ 25112 levels "","                                                                                                               "| __truncated__,..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ LATITUDE  : num  3040 3042 3340 3458 3412 ...
##  $ LONGITUDE : num  8812 8755 8742 8626 8642 ...
##  $ LATITUDE_E: num  3051 0 0 0 0 ...
##  $ LONGITUDE_: num  8806 0 0 0 0 ...
##  $ REMARKS   : Factor w/ 436781 levels "","-2 at Deer Park\n",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ REFNUM    : num  1 2 3 4 5 6 7 8 9 10 ...
#Show all the columns the weatherData dataframe object
colnames(weatherData)
##  [1] "STATE__"    "BGN_DATE"   "BGN_TIME"   "TIME_ZONE"  "COUNTY"    
##  [6] "COUNTYNAME" "STATE"      "EVTYPE"     "BGN_RANGE"  "BGN_AZI"   
## [11] "BGN_LOCATI" "END_DATE"   "END_TIME"   "COUNTY_END" "COUNTYENDN"
## [16] "END_RANGE"  "END_AZI"    "END_LOCATI" "LENGTH"     "WIDTH"     
## [21] "F"          "MAG"        "FATALITIES" "INJURIES"   "PROPDMG"   
## [26] "PROPDMGEXP" "CROPDMG"    "CROPDMGEXP" "WFO"        "STATEOFFIC"
## [31] "ZONENAMES"  "LATITUDE"   "LONGITUDE"  "LATITUDE_E" "LONGITUDE_"
## [36] "REMARKS"    "REFNUM"

EVTYPE, FATALITIES,INJURIES,PROPDMG, PROPDMGEXP,CROPDMG,CROPDMGEXP,LATITUDE,LONGITUDE,REFNUM

#Create a new variable with the columns needed
newData <- weatherData[,c("EVTYPE","FATALITIES","INJURIES","PROPDMG","PROPDMGEXP","CROPDMG","CROPDMGEXP","LATITUDE","LONGITUDE","REFNUM")]
#Check the first rows
head(newData)
##    EVTYPE FATALITIES INJURIES PROPDMG PROPDMGEXP CROPDMG CROPDMGEXP
## 1 TORNADO          0       15    25.0          K       0           
## 2 TORNADO          0        0     2.5          K       0           
## 3 TORNADO          0        2    25.0          K       0           
## 4 TORNADO          0        2     2.5          K       0           
## 5 TORNADO          0        2     2.5          K       0           
## 6 TORNADO          0        6     2.5          K       0           
##   LATITUDE LONGITUDE REFNUM
## 1     3040      8812      1
## 2     3042      8755      2
## 3     3340      8742      3
## 4     3458      8626      4
## 5     3412      8642      5
## 6     3450      8748      6
newData$PROPDMGEXP2 <- as.numeric(newData$PROPDMGEXP)

#Replace the abbreviations with numbers

newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "K"] <- as.factor(1000)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "M"] <- as.factor(1e+06)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == ""] <- as.factor(1)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "B"] <- as.factor(1e+091)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "m"] <- as.factor(1e+06)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "0"] <- as.factor(1)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "5"] <- as.factor(1e+05)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "6"] <- as.factor(1e+06)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "4"] <- as.factor(10000)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "2"] <- as.factor(100)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "3"] <- as.factor(1000)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "h"] <- as.factor(100)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "7"] <- as.factor(1e+07)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "H"] <- as.factor(100)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "1"] <- as.factor(10)
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "8"] <- as.factor(1e+08)

#Replace these values for NAs
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "+"] <- NA
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "-"] <- NA
newData$PROPDMGEXP2[newData$PROPDMGEXP2 == "?"] <- NA
newData$PROPCASH <- newData$PROPDMG * as.numeric(newData$PROPDMGEXP2)

newData$PROPDMGEXP2 <- as.numeric(newData$PROPDMGEXP2)

summary(newData$PROPDMGEXP2)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   1.000   1.000   1.000   8.758  17.000  19.000
# Exploring the crop exponent data
unique(newData$CROPDMGEXP)
## [1]   M K m B ? 0 k 2
## Levels:  ? 0 2 B k K m M
newData$CROPDMGEXP2 <- as.numeric(newData$CROPDMGEXP)

# Replace the abbreviations with numbers 
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "M"] <- as.factor(1e+06)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "K"] <- as.factor(1000)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "m"] <- as.factor(1e+06)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "B"] <- as.factor(1e+09)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "0"] <- as.factor(1)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "k"] <- as.factor(1000)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "2"] <- as.factor(100)
newData$CROPDMGEXP2[newData$CROPDMGEXP2 == ""] <- as.factor(1)

newData$CROPDMGEXP2[newData$CROPDMGEXP2 == "?"] <- NA
newData$CROPCASH <- newData$CROPDMG * newData$CROPDMGEXP2

RESULTS

Which types of events are most harmful to population health?

-Injuried by Events

#Barplot of Injuried by events
barplot(head(sort(xtabs(INJURIES ~ EVTYPE, newData), decreasing = TRUE), 12), las = 2, main = "Total Injuried by event")

  • Deaths by Events
barplot(head(sort(xtabs(FATALITIES ~ EVTYPE, newData), decreasing = TRUE), 12), las = 2,main = "Total Deaths by event")

  • As above charts show, the TORNADO event has caused most harmful to population health.

Which types of events have the greatest economic consequences?

  • Damages to properties and crops by Event
par(mfrow = c(1,2))
barplot(head(sort(xtabs(PROPCASH ~ EVTYPE, newData), decreasing = TRUE), 12), las = 2, main = "Damages to properties by event")
barplot(head(sort(xtabs(CROPCASH ~ EVTYPE, newData), decreasing = TRUE), 12), las = 2, main = "Damages to crops by event")

The types of events that have the greatest consequences are TORNADOS and HAIL