To shed light on the challenges of cleaning and preprocessing Big Data, we asked founders and co-founders to share their experiences. From overcoming incomplete records to processing unstructured data for analysis, here are the top five examples these leaders shared on how they ensured data quality in the face of challenges.
- Overcome Incomplete Records
- Correct GPS Data Discrepancies
- Address Missing Values
- Manage Big Data Complexity
- Process Unstructured Data for Analysis
Overcome Incomplete Records
One frequent data-cleansing challenge I encounter is dealing with incomplete records and missing values. This is especially common in large, aggregated data sets. The gaps can severely skew analysis if not addressed properly.
For example, we were assessing customer churn and found null values for several key user attributes. Dropping those records would diminish our sample size, so imputation was needed. After testing multiple methods, a random forest model proved most effective at predicting the missing variables.
We trained the model on the complete records, then used it to fill in the nulls. This maintained sample size while minimizing bias. The resulting complete data allowed us to identify predictive factors behind churn with much greater confidence.
Creative workarounds like imputation models prevent missing data from undermining the validity of results. A keen understanding of statistical methods equips data scientists to handle messy data at scale.
Ankit PrakashFounder, Sprout24
Correct GPS Data Discrepancies
In the vehicle-hire business, we amass a significant amount of data daily, from customer bookings to vehicle telemetry. One particular challenge was with GPS data from our fleet. We noticed discrepancies in vehicle location data, which would occasionally show a car in the middle of a body of water or off-road. This not only impacted fleet management but also billing accuracy.
To address this, we implemented a two-fold solution. First, we integrated a geospatial correction algorithm that would cross-reference raw GPS data with known road networks to rectify anomalies. Second, we applied outlier detection methods to identify and flag data points that deviated significantly from typical vehicle movement patterns.
By combining these techniques, we enhanced the integrity of our big data, ensuring accuracy in fleet management, billing, and overall user experience.
James McNallyManaging Director, SDVH [Self Drive Vehicle Hire]
Address Missing Values
One significant challenge encountered was handling missing values within a large dataset. During a data analytics project, we noticed that some critical fields were frequently blank or contained incorrect placeholders, which could lead to skewed results.
To overcome this, we conducted an analysis to understand the pattern of the missing values. We decided that imputation, rather than deletion, would be the most appropriate solution for our particular context. By using statistical methods like median or mean imputation, and sometimes employing predictive models to estimate the missing values, we maintained the integrity of the dataset without losing essential information.
The key was in understanding the missing data and choosing an approach that aligned with the overall goals of our analysis. This experience emphasized the importance of meticulous data exploration and employing tailored solutions to ensure the quality and reliability of our insights.
Brian ClarkFounder and CEO, United Medical Education
Manage Big Data Complexity
One of the biggest challenges we face with big data is its complexity. Most of the time, it is unstructured, noisy, and comes from multiple sources, which can make it difficult to extract insights and draw accurate conclusions.
In such a scenario, we organize and store data to make it easy to access and use advanced analytics techniques, such as machine learning and artificial intelligence, to identify patterns and insights in the data.
Miranda BenceCEO, CMO, Entrepreneur, Cheery Picks Reviews
Process Unstructured Data for Analysis
One challenge encountered in cleaning and preprocessing Big Data is handling unstructured data, such as text, images, or videos. Unstructured data lacks a predefined format and requires specialized techniques.
For example, consider extracting insights from customer reviews. Processing text data involves techniques like natural language processing (NLP) for sentiment analysis, topic modeling, or named entity recognition. By utilizing NLP libraries and algorithms, we can preprocess the text, tokenize it, remove stop words, and perform stemming or lemmatization. This ensures data quality by converting unstructured text into structured formats amenable to analysis.
Additionally, techniques like computer vision or audio processing can be applied to images or videos for feature extraction. Overcoming the challenge of preprocessing unstructured data is crucial for obtaining meaningful insights and ensuring data quality in Big Data analysis.
Roy LauCo-Founder, 28 Mortgage