Population health and Economic consequences of Storms

Synopsis

In this report we aim to describe types of events that are most harmful with respect to population health and economic consequences.The basic goalto explore the NOAA Storm Database and answer two basic questions about severe weather events.We use the database to answer the questions below and show the code for your entire analysis. My analysis can consist of tables, figures, or other summaries.The events in the database start in the year 1950 and end in November 2011. In the earlier years of the database there are generally fewer events recorded, most likely due to a lack of good records. More recent years should be considered more complete.

Data Processing

From the Storm Data we obtain the data on the types of events, fatalities, injuries, property damage and crop damage. We are addressing two questions: 1) Across the United States, which types of events (as indicated in the EVTYPE variable) are most harmful with respect to population health?

2) Across the United States, which types of events have the greatest economic consequences?

Fetching reading from the data

repdata-data-StormData.csv is read using read.csv command

data <- read.csv("repdata-data-StormData.csv")

To address the question: Across the United States, which types of events (as indicated in the EVTYPE variable) are most harmful with respect to population health? I read number of fatalities and injured people to evaluate the population health

fatal <- data$FATALITIES
injured <- data$INJURIES
health <- fatal + injured

Checking the that there are no NA term in the health data

for (i in 1:length(health)) {
    if (is.na(health[i])) {
        print("yes")
    }
}

Calculating the total health effect due to type of events

effect <- tapply(health, data$EVTYPE, sum)

Sorting the values of health effect in decreasing order to see which types of events are most harmful with respect to population health

top <- head(sort(effect, decreasing = TRUE))

To answer the question: Across the United States, which types of events have the greatest economic consequences? I have calculated the total amount of property damage by taking product od property damage and have interpreted the property damage exponent and to calculate crop damage by taking product of crop damage and interpreted the propert damage exponent. I have assumed the value of 0 of “”, ? etc.

total <- numeric()
for (i in 1:length(data$PROPDMGEXP)) {
    if (data$PROPDMGEXP[i] == "K") {
        total[i] <- data$PROPDMG[i] * 1000
    } else if (data$PROPDMGEXP[i] == "M") {
        total[i] <- data$PROPDMG[i] * 1e+06
    } else if (data$PROPDMGEXP[i] == "B") {
        total[i] <- data$PROPDMG[i] * 1e+09
    } else {
        total[i] <- 0
    }

    if (data$CROPDMGEXP[i] == "K") {
        total[i] <- total[i] + data$CROPDMG[i] * 1000
    } else if (data$CROPDMGEXP[i] == "M") {
        total[i] <- total[i] + data$CROPDMG[i] * 1e+06
    } else if (data$CROPDMGEXP[i] == "B") {
        total[i] <- total[i] + data$CROPDMG[i] * 1e+09
    } else {
        total[i] <- total[i] + 0
    }
}

Calculating the total economic effect due to type of events

eco_effect <- tapply(total, data$EVTYPE, sum)

Sorting the values of economic effect in decreasing order to see which types of events have the greatest economic consequences

eco_top <- head(sort(eco_effect, decreasing = TRUE))

Results

In order to answer which types of events are most harmful with respect to population health we are making pie chart and showing the results I am printing the head of the types of events but i have put pie chart command of whole data set in comment

head(top)

##        TORNADO EXCESSIVE HEAT      TSTM WIND          FLOOD      LIGHTNING 
##          96979           8428           7461           7259           6046 
##           HEAT 
##           3037

pie(top, names(top), main = "Health effect of events")

# pie(effect,names(effect))

From the pie chart we can clearly see that TORNADO has the greatest economic consequences and then the orders follow which can be seen in head(top) command

In order to answer which types of events have the greatest economic consequences we are making pie chart and showing the results I am printing the head of the types of events but i have put pie chart command of whole data set in comment

head(eco_top)

##             FLOOD HURRICANE/TYPHOON           TORNADO       STORM SURGE 
##         1.503e+11         7.191e+10         5.734e+10         4.332e+10 
##              HAIL       FLASH FLOOD 
##         1.875e+10         1.756e+10

pie(eco_top, names(eco_top), main = "Economic consequences of events")

# pie(eco_effect,names(eco_effect))

From the pie chart we can clearly see that FLOOD has the greatest economic consequences and then the orders follow which can be seen in head(eco_top) command