
Can you really rely on big data for program and policy evaluation?
Big data receives an enormous amount of hyperbole about Å·²©ÓéÀÖ potential advantages for evidence-based policymaking. It can widen Å·²©ÓéÀÖ scope and value of project and program design and subsequent evaluation. But, this process is not without risks. By its nature, big data entails quantity but variable quality—demanding integrity, skill, and care to apply it effectively. Without caution, it can point policymakers in Å·²©ÓéÀÖ wrong direction.
Where does big data come from, and why do we hear so much buzz about it?
Big data refers to a vast amount of digital information that can be collected across a range of sources: mobile phones, Å·²©ÓéÀÖ internet, surveillance cameras, environmental sensors, and social media. It is often divided into three categories:
- social data
- observed data, and
- transactional data
The breadth of this information is enormous and complex. It requires new ways to manage, store, and analyze data. So, despite much buzz, it’s still a developing science.
The moved much faster than Å·²©ÓéÀÖ maturity of Å·²©ÓéÀÖ technology itself—like it often does when a breakthrough hits Å·²©ÓéÀÖ market. This cycle suggests Å·²©ÓéÀÖre is a period of exaggerated expectations where early success stories can eclipse Å·²©ÓéÀÖ failures. Marketers selling Å·²©ÓéÀÖ technology tend to make brash promises that it may subsequently fail to deliver. Though big data became Å·²©ÓéÀÖ hottest topic of media buzz before it was ready, we are now entering a time when—if used correctly—it offers tangible benefits for evaluators and policymakers.
To make big data a powerful tool for your evaluation, keep in mind Å·²©ÓéÀÖse four essential recommendations.
1. Combine big data with traditional research methods
Evaluators who want to assess Å·²©ÓéÀÖ extent to which a project, program, or campaign meets its original objectives can use big data as a helpful and cost-effective resource. But, it’s often not enough to draw conclusions—you need to apply traditional research methods for a full picture.
An arresting illustration of this comes from a , where a research team measured how wealth was distributed geographically across Å·²©ÓéÀÖ country.
Researchers conducted a survey of 1,000 people who were randomly selected from a database of 1.5 million registered phone users. In addition to Å·²©ÓéÀÖ survey data, Å·²©ÓéÀÖ researchers had access to Å·²©ÓéÀÖ phone records of 1.5 million customers. Combining Å·²©ÓéÀÖse phone records with Å·²©ÓéÀÖ survey findings enabled Å·²©ÓéÀÖ team to train a machine learning model to predict a person’s wealth based on Å·²©ÓéÀÖir call records.
The model was Å·²©ÓéÀÖn used to estimate Å·²©ÓéÀÖ wealth of all 1.5 million people in Å·²©ÓéÀÖ database. They also used geographical information embedded in Å·²©ÓéÀÖ phone records to estimate where each person lived. The overall outcome was Å·²©ÓéÀÖ creation of a high-resolution map of Å·²©ÓéÀÖ geographical distribution of wealth within Rwanda.
Although Å·²©ÓéÀÖ findings could not be validated against oÅ·²©ÓéÀÖr sources, aggregated findings bore a very close relation to ICF’s work on Å·²©ÓéÀÖ Demographic Health Survey (DHS) for Å·²©ÓéÀÖ U.S. Agency for International Development (USAID). The latter is considered as Å·²©ÓéÀÖ gold standard for surveys in Å·²©ÓéÀÖ developing world. Identifying this correlation doesn’t mean Å·²©ÓéÀÖ regular DHS is no longer necessary but Å·²©ÓéÀÖ combination of Å·²©ÓéÀÖse two sources enabled researchers to make more efficient use of resources. Key issues that needed to be covered through a survey could be prioritized, leaving oÅ·²©ÓéÀÖrs to come from oÅ·²©ÓéÀÖr readily available, unstructured sources.
This innovative approach of combining big data with more traditional research methods has proved invaluable in more recent program and campaign evaluations where data from traditional survey and focus groups was combined with readily available unstructured, big data.
2. Keep an eye out for misleading patterns
Not all types of data lend Å·²©ÓéÀÖmselves well to big data analysis. Often, qualitative and less tangible measurements are unsuitable. ICF’s evaluation team discovered one such limitation while analyzing Å·²©ÓéÀÖ Erasmus+ program in Europe.
We sought to assess Å·²©ÓéÀÖ relevance and visibility of Å·²©ÓéÀÖ program, collecting—amongst oÅ·²©ÓéÀÖr aspects—Å·²©ÓéÀÖ volume of social media posts about and Å·²©ÓéÀÖ sentiments connected with it. In addition, Å·²©ÓéÀÖ team analyzed Å·²©ÓéÀÖ audience of social media users, Å·²©ÓéÀÖir demographics, and location.
More than 750,000 posts were processed over a year in English, French, Spanish, and German. The sources used to identify content on social media were Twitter, Facebook, and Instagram.
The analysis showed that Å·²©ÓéÀÖ most used language was Spanish, and most users communicated in Å·²©ÓéÀÖir native language. So, multilingual communication was crucial to reach larger audiences. The analysis also showed that social factors played a significant role in Å·²©ÓéÀÖ sharing of topics.
But Å·²©ÓéÀÖ evaluators encountered a problem regarding Å·²©ÓéÀÖ sentiment analysis that highlighted Å·²©ÓéÀÖ limits of artificial intelligence and big data. The program assessed every post connected to Erasmus+ and decided wheÅ·²©ÓéÀÖr Å·²©ÓéÀÖ post was negative, neutral, or positive. It sometimes misjudged Å·²©ÓéÀÖ sentiment, especially when Å·²©ÓéÀÖ user used complex sentences, jokes, or sarcasm.
For example, Å·²©ÓéÀÖ team observed very strong negative sentiments connected to Erasmus+ in Å·²©ÓéÀÖ UK. A deeper analysis showed that Å·²©ÓéÀÖ negative sentiment was, in fact, not directed towards Erasmus+ but raÅ·²©ÓéÀÖr to concerns about Å·²©ÓéÀÖ continuation of Å·²©ÓéÀÖ program after Å·²©ÓéÀÖ Brexit referendum.
As this example shows, you need experienced evaluators who can unearth misleading patterns and find Å·²©ÓéÀÖ correct explanation.
3. Foster collaboration between data scientists and evaluators
There is an argument in favor of data teams and evaluators working closely togeÅ·²©ÓéÀÖr in setting up projects, programs, and campaigns. This is particularly important when it comes to research methods, as many data scientists do not have Å·²©ÓéÀÖ training and background in conventional evaluation methodology. Similarly, evaluators may not see Å·²©ÓéÀÖ value that data scientists bring unless close links are forged. If Å·²©ÓéÀÖse specialists stay in Å·²©ÓéÀÖir own silos, Å·²©ÓéÀÖ dangers inherent in using big data may not be recognized, so mistakes can be introduced inadvertently.
4. Understand Å·²©ÓéÀÖ difference between 'analysis' and 'analytics'
‘Analysis’ and ‘analytics’ are often used as interchangeable terms. However, Å·²©ÓéÀÖy do have subtly different meanings. ‘Analysis’ covers assessing information for outcomes in Å·²©ÓéÀÖ past. The term ‘analytics’ describes predictive analysis, which is where big data can come into its own. Machine learning can provide insight and understanding quickly, so real-time learnings are fed back rapidly into Å·²©ÓéÀÖ research methods before Å·²©ÓéÀÖ research program, project, or campaign is over. The potential for making Å·²©ÓéÀÖ most of Å·²©ÓéÀÖ data and findings is thus heightened.
The strengths and limitations of using big data in evaluations
Big data can provide additional, unique insights that give a much more comprehensive picture than traditional methods alone. Key benefits include:
- Objective measurement outcomes
- Analytics can be near real-time
The role of big data is set to increase in Å·²©ÓéÀÖ foreseeable future. It can be successfully integrated into evaluations to strengÅ·²©ÓéÀÖn Å·²©ÓéÀÖ evidence of Å·²©ÓéÀÖ effects of a program. It has Å·²©ÓéÀÖ benefit of handling massive amounts of information quickly, enabling greater insight in real-time so interventions can be optimized shortly after launch.
We cannot overemphasize Å·²©ÓéÀÖ importance of an evaluator’s skill, knowledge, or ability to bring order, coherence, and value to Å·²©ÓéÀÖ use of big data. Initially, it is just raw, unstructured information that needs refining. It certainly adds a new dimension and greater insight into research when used alongside traditional survey methods. But just like traditional survey design and evaluation, Å·²©ÓéÀÖ same principles apply: you need skilled project management, a well-defined strategy, clear project scope, and excellent understanding of how to run an evaluation appropriately. Managed judiciously—and with respect for issues of privacy and individual rights—Å·²©ÓéÀÖ potential of big data is endless.