Contents

• Introduction
• File Organization
• Questions
• Conclusion

The Sample Beer Case Study is designed and developed to understand and shed light on the relationship or correlation, if any, of the two variables IBU vs. ABV, that is, International Bitterness Units of a certain Beer vs. Alcohol by Volume of the certain Beer. This Study samples from various Breweries throughout the United States.

Resembles the following Model:

• Images contained in a subdirectory of Data called Img
• Description of all known variables contained in the Data directory as a markdown file.

library(readr)
Breweries <- read_csv("C:/Users/146st/R_Project_Repo/CaseStudy01/Data/Breweries.csv")
View(Breweries)
str(Breweries)
table(Breweries$State)  

The table(Breweries$State) command gives the values of Breweries in each State:

AK AL AR AZ CA CO CT DC DE FL GA HI IA ID IL IN KS KY LA MA MD ME MI MN MO MS MT NC ND NE NH NJ NM NV NY OH OK OR PA RI SC 7 3 2 11 39 47 8 1 2 15 7 4 5 5 18 22 3 4 5 23 7 9 32 12 9 2 9 19 1 5 3 3 4 2 16 15 6 29 25 5 4 SD TN TX UT VA VT WA WI WV WY 1 3 28 4 16 10 23 20 1 4

library(readr)
Beers <- read_csv("C:/Users/146st/R_Project_Repo/CaseStudy01/Data/Beers.csv")
View(Beers)
Brew_ID<-Beers$Brewery_id
colnames(Beers)[5]<-"Brew_ID"
View(Beers)
BrewBeers <- merge(x = Beers, y = Breweries, by = "Brew_ID", all = TRUE)
View(BrewBeers)
head(BrewBeers)
tail(BrewBeers)

Here's the head of the output of the merge data set, first 6 rows!

Brew_ID Name.x Beer_ID ABV IBU Style Ounces Name.y City State 1 1 Get Together 2692 0.045 50 American IPA 16 NorthGate Brewing Minneapolis MN 2 1 Maggie's Leap 2691 0.049 26 Milk / Sweet Stout 16 NorthGate Brewing Minneapolis MN 3 1 Wall's End 2690 0.048 19 English Brown Ale 16 NorthGate Brewing Minneapolis MN 4 1 Pumpion 2689 0.060 38 Pumpkin Ale 16 NorthGate Brewing Minneapolis MN 5 1 Stronghold 2688 0.060 25 American Porter 16 NorthGate Brewing Minneapolis MN 6 1 Parapet ESB 2687 0.056 47 Extra Special / Strong Bitter (ESB) 16 NorthGate Brewing Minneapolis MN

summary(BrewBeers)

We see that two columns have NA's ABV and IBU, which is 62 and 1005 respectively.

require(ggplot2)
MedIBU<-aggregate( IBU ~ State, data=BrewBeers, FUN=median)
IBU_PLOT<-ggplot(na.omit(MedIBU), aes(x=reorder(State, IBU), y=IBU)) + geom_bar(stat="identity") + coord_flip()
IBU_PLOT
#First the IBU and now the ABV conversion
MedABV<-aggregate( ABV ~ State, data=BrewBeers, FUN=median)
ABV_PLOT<-ggplot(na.omit(MedABV), aes(x=reorder(State, ABV), y=ABV)) + geom_bar(stat="identity")+ coord_flip()
ABV_PLOT

Here are the Charts:

#First the Acohol by Volume State and Amount
BrewBeers[which.max(BrewBeers$ABV), ]$State
BrewBeers[which.max(BrewBeers$ABV), ]$ABV
#Next the International Bitterness Unit of Beer by State and Unit
BrewBeers[which.max(BrewBeers$IBU), ]$State
BrewBeers[which.max(BrewBeers$IBU), ]$IBU

BrewBeers[which.max(BrewBeers$ABV), ]$State [1] "CO" BrewBeers[which.max(BrewBeers$ABV), ]$ABV [1] 0.128 BrewBeers[which.max(BrewBeers$IBU), ]$State [1] "OR" BrewBeers[which.max(BrewBeers$IBU), ]$IBU [1] 138

# Five point summary including # of NA's and the Mean.
summary(BrewBeers$ABV)

summary(BrewBeers$ABV) Min. 1st Qu. Median Mean 3rd Qu. Max. NA's 0.00100 0.05000 0.05600 0.05977 0.06700 0.12800 62

#Scattered Plot
ggplot(na.omit(BrewBeers), aes(x=ABV, y=IBU)) + geom_point()

# Pearson r correlation 
rcorr <- cor.test(BrewBeers$ABV, BrewBeers$IBU, method = "pearson")
rcorr

This result shows a moderatly postive correlation between the two variables IBU and ABV.

rcorr <- cor.test(BrewBeers$ABV, BrewBeers$IBU, method = "pearson") rcorr Pearson's product-moment correlation

data: BrewBeers$ABV and BrewBeers$IBU t = 33.863, df = 1403, p-value < 2.2e-16 alternative hypothesis: true correlation is not equal to 0 95 percent confidence interval: 0.6407982 0.6984238 sample estimates: cor 0.6706215

The Sample Brewery Beer Case Study is considered an Observational Study. Although there is evidence of a positive correlation between taste of bitterness and strength of alcohol beverage, we cannot use our study to infer anything about the broader scope of the relationship between IBU and ABV. Perhaps one can go out and try it for oneself, since people do have different tastes buds and tolerance to certain levels of Alcohol, and their own opinions on the matter.