Back to blog

The Critical Role of Data Cleaning

Lukas Racickas

Updated on Jun 06, 2024
Published on Jun 06, 2024
the importance of data cleaning

Key takeaways

  • Data cleaning is one of the first steps of the data processing cycle
  • Cleaning eliminates outliers, irrelevant data, and fixes missing values
  • Large language models (LLMs) can help to clean the data more efficiently by identifying duplicates, standardizing and enriching the data

As a product manager, I have closely worked with data engineering teams and witnessed the fantastic ways to transform raw web data into insights, products, data models, and more. Data cleaning consistently stands out as a vital component.

In this article, we’ll delve into the role that data cleaning, also referred to as data cleansing or scrubbing, plays within the data processing chain and its contribution to the success of utilizing the potential of web data to the fullest.

The data processing chain

Before exploring the depths of data processing and cleaning, let’s get a better handle on these concepts. Processing is a broader definition while cleaning is a particular step.

The data processing cycle, also known as the data lifecycle, refers to the steps involved in transforming raw data into readable and usable information. It typically begins with data collection from various sources such as sensors, surveys, or publicly available online data sources. The next stage involves data preparation, where the collected data is cleaned, structured, and enriched to make it suitable for analysis.

Data analysis follows, where statistical techniques and machine learning algorithms are employed to extract meaningful patterns and insights from the data. Finally, the processed data informs decision-making, improves products and services, or creates new business opportunities.

Consider a scenario where a company collects web data to create a B2B software product. If a company relies on scraped web data, this raw data is often unstructured or semi-structured and contains errors and inconsistencies.

Enter data cleaning. Data cleaning ensures the quality and reliability of the data before it moves to the next stage. This step removes most errors and irrelevant data, and inconsistencies are fixed.

Next, the cleaned data undergoes feature engineering, transforming it into a format suitable for analysis and modeling. Lastly, processed data must be stored in a way that allows for easy retrieval and analysis.

Ultimately, this chain of processes enables businesses to create data-driven insights and products.

The importance of data cleaning

Data cleaning is a crucial step that eliminates irrelevant data, identifies outliers and duplicates, and fixes missing values. It involves removing errors, inconsistencies, and, sometimes, even biases from raw data to make it usable. While buying pre-cleaned data can save resources, understanding the importance of data cleaning is still essential.

Inaccuracies can significantly impact results. In many cases, before the removal of low-value data, the rest is still hardly usable. Cleaning works as a filter, ensuring that data passes through to the next step, which is more refined and relevant to your goals.

Besides enabling you to work with more readable, accurate, and reliable data, here are a couple of other reasons why data cleaning is essential:

  • It helps to uncover hidden patterns and trends in data;
  • It significantly improves the speed and reduces the complexity of data analysis.

The importance of data cleaning for AI

As in recent years the development of AI-based solutions keeps accelerating, it poses many challenges, such as how to ensure their reliability in terms of accuracy. It requires large amounts of data. Flawed data can lead to flawed AI models, so cleaning is essential in developing AI applications because it ensures that the data used for training AI models is accurate and consistent.

For instance, in the healthcare industry, AI models diagnose diseases and recommend treatments. If the data used to train these models contains errors, such as duplicate or outdated patient records, the models may make incorrect diagnoses or prescribe inappropriate treatments.

Furthermore, data cleaning is pivotal in uncovering hidden patterns and relationships in complex datasets. It makes it possible to extract meaningful insights from data by eliminating irrelevant or redundant information.

For example, AI algorithms are employed in the finance sector to predict market trends and optimize portfolio allocation. Cleaning the financial data removes noise and outliers that may distort or confound the models, leading to more precise predictions and informed investment decisions.

At its core, data cleaning is the backbone of robust and reliable AI applications. It helps guard against inaccurate and biased data, ensuring AI models and their findings are on point. Data scientists depend on data cleaning techniques to transform raw data into a high-quality, trustworthy asset. AI systems can effectively leverage the data to generate valuable insights and achieve game-changing outcomes.

Data cleaning ensures ethical and high-quality large language models

Another example of the importance of data cleaning is in developing large language models (LLMs). LLMs are used in various applications, including NLP, machine translation, and dialogue generation.

Suppose the processed data used to train LLMs contains inconsistencies and errors. The models may inherit these flaws and produce incorrect output. Data cleaning helps to remove these impurities from the training data, ensuring that LLMs are trained on reliable information.

Interestingly, LLMs that have been properly trained on clean data can play a significant role in the data cleaning process itself. Their advanced capabilities enable them to automate and enhance various data cleaning tasks, making the process more efficient and effective.

How LLMs can be used to clean data:

  • Deduplication of textual datasets: LLMs can identify and remove duplicates. This eliminates redundancy and ensures the accuracy of the dataset;
  • Data Standardization: LLMs can transform data into a consistent format by correcting spelling errors, converting units, and normalizing values. This simplifies data analysis and improves model performance;
  • Data Enrichment: LLMs can enhance data by filling in missing values, generating new data points, and providing context. This improves the completeness and quality of the dataset, leading to more robust AI models.

By leveraging these capabilities, LLMs can significantly enhance data cleaning processes and benefit businesses that need to speed up or improve their data engineering workflows.


Data cleaning is a critical step in the data processing cycle that can significantly impact the quality of data-driven initiatives. It is not just about removing errors and inconsistencies but also about ensuring the accuracy and reliability of data.

Businesses can make better decisions, gain improved insights, and enhance their predictive capabilities by investing in data cleaning or buying already cleaned datasets. I encourage readers to explore opportunities to use pre-cleaned data in their work and experience the benefits of cleaner, more reliable data firsthand.

This article was originally published on Data Science Central.