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At the core of modern AI projects are machine-learning-based systems which depend on data to derive their predictive power. Because of this, all artificial intelligence projects are dependent on high data quality.
However, obtaining and maintaining high quality data is not always easy. There are numerous data quality issues that threaten to derail your AI and machine learning projects. In particular, these nine data quality issues need to be considered and prevented before issues arise.
1. Inaccurate, incomplete and improperly labeled data
Inaccurate, incomplete or improperly labeled data is typically the cause of AI project failure. These data issues can range from bad data at the source to data that has not been cleaned or prepared properly. Data might be in the incorrect fields or have the wrong labels applied.
Data cleanliness is such an issue that an entire industry of data preparation has emerged to address it. While it might seem an easy task to clean gigabytes of data, imagine having petabytes or zettabytes of data to clean. Traditional approaches simply don't scale, which has resulted in new AI-powered tools to help spot and clean data issues.
2. Having too much data
Since data is important to AI projects, it's a common thought that the more data you have, the better. However, when using machine learning sometimes throwing too much data at a model doesn't actually help. Therefore, a counterintuitive issue around data quality is actually having too much data.
While it might seem like too much data can never be a bad thing, more often than not, a good portion of the data is not usable or relevant. Having to go through to separate useful data from this large data set wastes organizational resources. In addition, all that extra data might result in data "noise" that can result in machine learning systems learning from the nuances and variances in the data rather than the more significant overall trend.
3. Having too little data
On the flip side, having too little data presents its own problems. While training a model on a small data set may produce acceptable results in a test environment, bringing this model from proof of concept or pilot stage into production typically requires more data. In general, small data sets can produce results that have low complexity, are biased or too overfitted and will not be accurate when working with new data.
4. Biased data
In addition to incorrect data, another issue is that the data might be biased. The data might be selected from larger data sets in ways that doesn't appropriately convey the message of the wider data set. In other ways, data might be derived from older information that might have been the result of human bias. Or perhaps there are some issues with the way that data is collected or generated that results in a final biased outcome.
5. Unbalanced data
While everyone wants to try to minimize or eliminate bias from their data sets, this is much easier said than done. There are several factors that can come into play when addressing biased data. One factor can be unbalanced data. Unbalanced data sets can significantly hinder the performance of machine learning models. Unbalanced data has an overrepresentation of data from one community or group while unnecessarily reducing the representation of another group.
An example of an unbalanced data set can be found in some approaches to fraud detection. In general, most transactions are not fraudulent, which means that only a very small portion of your data set will be fraudulent transactions. Since a model trained on this fraudulent data can receive significantly more examples from one class versus another, the results will be biased towards the class with more examples. That's why it's essential to conduct thorough exploratory data analysis to discover such issues early and consider solutions that can help balance data sets.
6. Data silos
Related to the issue of unbalanced data is the issue of data silos. A data silo is where only a certain group or limited number of individuals at an organization have access to a data set. Data silos can result from several factors, including technical challenges or restrictions in integrating data sets as well as issues with proprietary or security access control of data.
They are also the product of structural breakdowns at organizations where only certain groups have access to certain data as well as cultural issues where lack of collaboration between departments prevents data sharing. Regardless of the reason, data silos can limit the ability of those at a company working on artificial intelligence projects to gain access to comprehensive data sets, possibly lowering quality results.
7. Inconsistent data
Not all data is created the same. Just because you're collecting information, that doesn't mean that it can or should always be used. Related to the collection of too much data is the challenge of collecting irrelevant data to be used for training. Training the model on clean, but irrelevant data results in the same issues as training systems on poor quality data.
In conjunction with the concept of data irrelevancy is inconsistent data. In many circumstances, the same records might exist multiple times in different data sets but with different values, resulting in inconsistencies. Duplicate data is one of the biggest problems for data-driven businesses. When dealing with multiple data sources, inconsistency is a big indicator of a data quality problem.
8. Data sparsity
Another issue is data sparsity. Data sparsity is when there is missing data or when there is an insufficient quantity of specific expected values in a data set. Data sparsity can change the performance of machine learning algorithms and their ability to calculate accurate predictions. If data sparsity is not identified, it can result in models being trained on noisy or insufficient data, reducing the effectiveness or accuracy of results.
9. Data labeling issues
Supervised machine learning models, one of the fundamental types of machine learning, require data to be labeled with correct metadata for machines to be able to derive insights. Data labeling is a hard task, often requiring human resources to put metadata on a wide range of data types. This can be both complex and expensive. One of the biggest data quality issues currently challenging in-house AI projects is the lack of proper labeling of machine learning training data. Accurately labeled data ensures that machine learning systems establish reliable models for pattern recognition, forming the foundations of every AI project. Good quality labeled data is paramount to accurately training the AI system on what data it is being fed.
Organizations looking to implement successful AI projects need to pay attention to the quality of their data. While reasons for data quality issues are many, a common theme that companies need to remember is that in order to have data in the best condition possible, proper management is key. It's important to keep a watchful eye on the data that is being collected, run regular checks on this data, keep the data as accurate as possible, and get the data in the right format before having machine learning models learn on this data. If companies are able to stay on top of their data, quality issues are less likely to arise.