17/07/2024
𝐈𝐧𝐟𝐞𝐫𝐞𝐧𝐭𝐢𝐚𝐥 𝐬𝐭𝐚𝐭𝐢𝐬𝐭𝐢𝐜𝐬 𝐢𝐧𝐯𝐨𝐥𝐯𝐞 𝐦𝐚𝐤𝐢𝐧𝐠 𝐢𝐧𝐟𝐨𝐫𝐦𝐞𝐝 𝐞𝐬𝐭𝐢𝐦𝐚𝐭𝐞𝐬 𝐨𝐫 𝐩𝐫𝐞𝐝𝐢𝐜𝐭𝐢𝐨𝐧𝐬 𝐚𝐛𝐨𝐮𝐭 𝐚 𝐥𝐚𝐫𝐠𝐞𝐫 𝐩𝐨𝐩𝐮𝐥𝐚𝐭𝐢𝐨𝐧 𝐨𝐫 𝐩𝐡𝐞𝐧𝐨𝐦𝐞𝐧𝐨𝐧 𝐛𝐚𝐬𝐞𝐝 𝐨𝐧 𝐚 𝐬𝐦𝐚𝐥𝐥𝐞𝐫 𝐬𝐚𝐦𝐩𝐥𝐞 𝐨𝐟 𝐝𝐚𝐭𝐚.
The concepts that fall under inferential statistics are 𝙥𝙤𝙥𝙪𝙡𝙖𝙩𝙞𝙤𝙣, 𝙨𝙖𝙢𝙥𝙡𝙚, and 𝙨𝙖𝙢𝙥𝙡𝙞𝙣𝙜.
𝙋𝙤𝙥𝙪𝙡𝙖𝙩𝙞𝙤𝙣
Think of the population as the big group you want to know something about.
𝙎𝙖𝙢𝙥𝙡𝙚
Since it's often too hard to study everyone in the population, you pick a smaller group, called a sample.
𝙎𝙖𝙢𝙥𝙡𝙞𝙣𝙜
Sampling is the process of picking that smaller group (the sample) so it represents the big group (the population) well.
𝑬𝒙𝒂𝒎𝒑𝒍𝒆
Imagine you have 𝐚 𝐛𝐚𝐠 𝐨𝐟 𝐦𝐚𝐫𝐛𝐥𝐞𝐬 (𝐩𝐨𝐩𝐮𝐥𝐚𝐭𝐢𝐨𝐧), and you want to know the average color of all the marbles. Instead of looking at every marble, you 𝐫𝐚𝐧𝐝𝐨𝐦𝐥𝐲 (𝐬𝐚𝐦𝐩𝐥𝐢𝐧𝐠 𝐩𝐫𝐨𝐜𝐞𝐬𝐬) pick out 𝟐𝟎 𝐦𝐚𝐫𝐛𝐥𝐞𝐬 (𝐬𝐚𝐦𝐩𝐥𝐞). By studying these 20 marbles, you're making a smart guess about the average color of all the marbles in the bag. That's inferential statistics in action.
