Kanngongkanngoen

Basic Statistics 101: A Complete Beginner’s Guide

💡 Key takeaways

An introduction to core statistics concepts, from research design and representative samples to mean, median, mode, variability, box plots, z-scores, and the empirical rule.

Welcome to the world of statistics! This article introduces Basic Statistics 101, from fundamentals to more advanced ideas. Whether you are a student or a professional looking to build your statistics knowledge, it can help you understand key principles and apply them to data analysis. We begin with the importance of good research design and move on to tools for analyzing data so you can put these ideas to practical use.

Introduction to statistics

A good way to begin learning statistics is to understand research design, because the quality of statistical analysis depends greatly on how a study is designed.

Research design

Research design is central to understanding data and results. A good design helps you collect data accurately and reliably.

Random sampling

Random sampling is the best method for collecting data. It helps ensure that the collected data represents the entire population.

Representative data

Representative data is very important for accurate and reliable results. It can help you draw conclusions about and understand a population.

Data collection

Data collection is an important step in statistical analysis. Choose a method suited to your research question.

Central tendency

Central tendency measures the center of a data set and can help us understand its overall pattern.

Mean, median, and mode

The mean, median, and mode are measures of central tendency. The mean is the sum of all data values divided by the number of values. The median is the middle value after sorting the data from lowest to highest. The mode is the value that appears most often in a data set.

Skewness

Skewness measures how asymmetric a data distribution is. Skewness can affect which measure of center is suitable. For highly skewed data, the median may be a better choice than the mean.

GDP per capita

GDP per capita, or gross domestic product per capita, is an important economic measure that represents the average income per person in a country.

Variability

Variability measures how spread out data is and helps us understand how much values differ from one another.

Variance and standard deviation

Variance and standard deviation measure the spread of data. Variance is the average of the squared differences between each value and the mean. Standard deviation is the square root of the variance.

Measures of position

Measures of position show where a data value sits in relation to other values in a data set.

Box plot

A box plot is a useful way to visualize data and see the overall spread. It shows the minimum, maximum, first quartile, second quartile (the median), and third quartile.

Outliers

Outliers are values that differ substantially from other values in a data set. They can affect data analysis, so they need to be handled carefully.

Normal distribution

The normal distribution is one of the most important distributions in statistics. It has a bell-shaped curve.

Z-score

A z-score is used to standardize data. It tells us how many standard deviations a value lies from the mean.

Empirical rule

The empirical rule applies to normally distributed data. It states that about 68% of values fall within one standard deviation of the mean, 95% within two standard deviations, and 99.7% within three standard deviations.


💬 Get free financial guidance from an expert. Click to add us on LINE.


👉 Add us on LINE for a free consultation


Or scan the QR code to add us.

QR Code Line

KGK

Kanngongkanngoen Editorial Team

We create clear educational content about personal finance, investing, and debt management, with an emphasis on accuracy and transparency.