ChenNannan-Data preparation

ISSS608 Assign ChenNannan-MC2

Introduction

Data preparation

Insights

Conclusion

Data Quality Issues

• No missing value.

• At least 2.5% of 0 value in value variables which is meaningless.

• Year 1998 and 1999 are imported wrong. The time series range is from 1998 to 2016.

• Same location, sample date and measure have different value record.

Data Preparation

• Recode the sample date.

• Use the summary function to avoid duplication record by mean.

• 'Dcast' the data

• Standardize the value by each kinds of measure because different units.

• 'Melt' the data