Know the Data Collection Methods and Cleaning Techniques Contents data collection and cleaning: Data Collection Methods Data Quality Assessment Data Cleaning Techniques Outlier Detection Data Collection Methods Data Collection is the process of gathering relevant data from various sources that can be used for analysis. The two primary categories of data collection techniques are:      Primary Data Collection :  Primary data collection involves collecting data directly from the source for a specific purpose. This method involves the use of surveys, interviews, observations, and experiments to collect data.      Secondary Data Collection :  Secondary data collection involves the use of data that has already been collected and is available for public use. This method involves the use of data obtained from books, journals, newspapers, and government publications. Data Quality Assessment Data Quality Assessment is the process of evaluating th...