Study Note54 Qualitative Data vs Quantitatived Data Qualitative Data: - Qualitative data describes characteristics, qualities, or features non-numerically. - It is subjective and can be nominal or ordinal. - It is often expressed through text, images, or audio. - Examples include product colors, customer genders, satisfaction ratings, etc. - Qualitative data analysis often requires subjective interpretation and may involve .. 2024. 4. 24. Sampling Bias and Sample Error Sampling BiasSampling bias occurs when the process of selecting a sample from a population results in some members of the population being more likely to be included in the sample than others. This can lead to an inaccurate or misleading representation of the population, as certain groups may be overrepresented or underrepresented in the sample. It can arise from various factors such as non-rand.. 2024. 4. 24. Simpson's paradox Simpson's paradox How Data Trends Can MisleadSimpson's Paradox is a fascinating statistical phenomenon that can lead to misleading conclusions if not properly understood. I'll explore what Simpson's Paradox is and why it's important for data analysts and researchers to be aware of it. What is Simpson's Paradox?Simpson's Paradox occurs when a trend that appears in different groups of da.. 2024. 4. 24. Data literacy Data literacy is one of the important concepts in modern society. Simply put, data literacy refers to the ability of individuals or organizations to collect, understand, interpret, and utilize data. Data literacy is consist of 'Reading Data', Working with Data', and 'Communicating with Data'. 1. Reading Data: This aspect involves the ability to understand and interpret data. It includ.. 2024. 4. 24. Difference between COALESCE and IFNULL COALESCE COALESCE function in SQL is used to return the first non-NULL value among its arguments. It accepts multiple arguments and returns the first non-NULL value encountered. If all arguments are NULL, `COALESCE` returns NULL. Example: Suppose we have a table named `sales` with columns `product_id`, `sale_date`, and `sale_amount`. Some records in the `sale_amount` column might have NULL value.. 2024. 4. 23. Transaction Transaction "transaction" refers to a concept representing a series of database operations. Transactions ensure the properties of atomicity, consistency, isolation, and durability (ACID) in the database, which are essential for managing data reliably and securely. Explanation of each ACID property: 1. Atomicity: All operations within a transaction must be treated as an indivisible unit, meaning .. 2024. 4. 22. 이전 1 2 3 4 5 6 7 8 9 다음
