Pearson correlation - Scatterplot - Partial pearson correlation using R

A. Pearson correlation

Data

advert = c(4.69, 6.41, 5.47, 3.43, 4.39, 2.15, 1.54, 2.67, 1.24, 1.77, 4.46, 1.83, 5.15, 5.25, 1.72, 3.04, 4.92, 4.85, 3.13, 2.29, 4.9, 5.75, 3.61, 4.62)
sales = c(12.23, 11.84, 12.25, 11.1, 10.97, 8.75, 7.75, 10.5, 6.71, 7.6, 12.46, 8.47, 12.27, 12.57, 8.87, 11.15, 11.86, 11.07, 10.38, 8.71, 12.07, 12.74, 9.82, 11.51)

A1. Scatterplot

plot(advert, sales, xlab = "Advertisement", ylab = "Sales")

A2. Pearson correlation coefficient (along with significance).

cor.test(sales, advert)

B. Partial correlation coefficient

Data

funding = c(155.33, 177.34, 165.09, 154.28, 185.56, 186.96, 198.63, 172.14, 198.25, 193.9, 157.03, 158.07, 182.09, 173.2, 151.84, 182.9, 197.09, 163.86, 192.3, 172.03, 166.97, 187.86, 184.23, 166.86, 174.64, 159.5, 153.18, 169.46, 169.9, 161.57, 183.99, 187.98, 195.88, 154.76, 177.6, 163.02, 190.34, 179.27, 192.2, 181.23, 159.41, 167.47, 151.38, 195.56, 162.69, 173.17, 176.52, 200.73, 190.53, 180.12)
disease = c(158.34, 157.23, 162.92, 130.59, 202.81, 221.43, 189.22, 166.42, 203.07, 198.57, 161.79, 168.82, 180.41, 178.52, 157.77, 212.44, 198.9, 174.25, 212.07, 149.45, 190.35, 198.38, 172.99, 186.81, 179.42, 148.46, 133.64, 152.11, 183.13, 163.32, 176.52, 178.6, 207.62, 143.88, 159.74, 172.06, 188.55, 202.31, 190.16, 201.54, 153.99, 153.99, 122.39, 184.35, 154.44, 179.7, 167.49, 164.54, 184.12, 178.94)
visits = c(152.13, 167.84, 162.21, 146.69, 186.93, 188.16, 195.39, 175.5, 197.04, 190.16, 156.47, 159.21, 185.65, 176.5, 156.97, 181.62, 205.51, 167.09, 192.71, 165.02, 162.07, 186.16, 189, 166.93, 171.45, 157.3, 150.41, 171.18, 168.88, 151.86, 185.03, 184.52, 197.07, 153.74, 184.18, 155.93, 197.91, 187.9, 194.07, 186.68, 150.64, 164.11, 148.32, 193.66, 162.36, 172.7, 172.51, 196.14, 191.1, 174.83)

B1. Scatterplot and correlation coefficient

cor.test(funding, disease)
plot(funding, disease, xlab = "Funding", ylab = "Reported diseases", cex = 1.5, cex.lab = 1.5, cex.axis = 1.5)

B2. Partial correlation coefficient

library(ppcor)
pcor.test(funding, disease, visits)

The above example is contained in the paragraph 4.1 of the book "Στατιστική ανάλυση με τη γλώσσα R" (in Greek, ISBN: 978-960-93-9445-1) published in Thessaloniki, 2017.