8.1 Correlation plots
Luke Karelas
10/8/2019
In this exercise you will learn to visualize the pairwise relationships between a set of quantitative variables. To this end, you will make your own note of 8.1 Correlation plots from Data Visualization with R.
Q1 What factors have positve correlation with home price?
The Factors that have positive correlation with home price are Fireplaces, Bedrooms, Living Area, Rooms, Bathrooms, Land Value, PCT College, and Lot Size.
Q2 What factors have strong positve correlation with home price?
The factors that have a strong correlation with home price are Living Area and Bathrooms.
Q3 What factors have negative correlation with home price?
The only factor that has a negative correltion with home price is age, the older the home is the cheaper the price.
Q4 What factors have strong negative correlation with home price?
There are no factors that have a strong negative correlation with home price.
Q5 What set of two variables has the highest positive Pearson Product-Moment correlation coefficient? What set of two variables has the greatest negative Pearson Product-Moment correlation coefficient?
The two variables that have the highest positive correlation are Living area and Rooms. The two with the strongest negative correlation are bathrooms and age, this is still a weak correlation but the strongest negative correlation we have.
Q6 What set of two variables has the Pearson Product-Moment correlation coefficent that is closest to zero? Would you be sure that the two variables are not related at all? What would you do to check?
The two variables that are closest to 0 in terms of correlation are Age and Lot Size, or Age and Land Value because they have the same correlation of -.02. We are not sure that the two are not related at all just by looking at the correlation coefficent but can check by putting them in a scatterplot.
Q7 Plot correlation for CPS85 in the same way as above. Repeat Q1-Q6.
Hint: The CPS85 data set is from the mosaicData package. Explain wage instead of home price.
Q1 What factors have positve correlation with home price?
Exper, educ and age have a positive correlation
Q2 What factors have strong positve correlation with home price?
There are no variables that have a strong positive correlation with wage.
Q3 What factors have negative correlation with home price?
No factors have a negative correlation with wage.
Q4 What factors have strong negative correlation with home price?
No factors have a strong negative correlation with wage.
Q5 What set of two variables has the highest positive Pearson Product-Moment correlation coefficient? What set of two variables has the greatest negative Pearson Product-Moment correlation coefficient?
The two variables with the strongest positive correlation are age and exper. The two with the strongest negative correlation are Exper and Educ.
Q6 What set of two variables has the Pearson Product-Moment correlation coefficent that is closest to zero? Would you be sure that the two variables are not related at all? What would you do to check?
The two variables that have a correlation coefficent closest to 0 are Age and Wage with a correlation of .09. We cannot be sure if they are not related at all just by looking at the correlation coefficent. We can check by putting them in a scatterplot.
Q8 Hide the messages, the code and its results on the webpage.
Hint: Use message, echo and results in the chunk options. Refer to the RMarkdown Reference Guide.