Banking


October 17, 2024by Cristian0

Our latest preprint is out! Check it out on ArXiV.

Imagine making important decisions—like adjusting credit limits or recommending treatments—where there are multiple options instead of only “yes or no”. In our latest research, we asked whether traditional methods of estimating causal effects are enough for these complex situations. But what exactly is a causal effect? Simply put, a causal effect measures how one action directly impacts an outcome—like how increasing a credit limit might influence a customer’s spending behavior. Typically, these causal estimates help us make the “best” decision, but we found they don’t always tell the whole story.

Our study dives into what’s called a “multitreatment scenario”, where the range of possible actions isn’t limited to just one choice. For example, adjusting a credit limit could involve not only deciding whether to change it, but also determining by how much. In our case, the outcome we aimed to optimize was continuous—for instance the expected profit from adjusting credit card limits, and also the outcome was observable both before and after treatment.

We explored a new method that combines causal effect estimation with additional criteria like uncertainty measures and a “prediction condition”.  To truly enhance decision quality, we went beyond the traditional methods and added a fresh perspective. We brought in a measure called Conditional Value at Risk (CVaR), which allowed us to understand potential worst-case scenarios, not just the average outcome. Think of CVaR as a safety net that ensures we don’t overlook possible downsides while aiming for the best result.

We also introduced a “predictive condition” to help ensure our recommendations would actually be beneficial. Essentially, the predictive condition means we only recommend an action if we can confidently predict that the outcome will improve compared to where it started. In the context of adjusting credit limits, this meant that any suggested change had to show a clear increase in expected profit compared to the one corresponded to the original limit. This safeguard adds another layer of confidence, making sure that each decision made was a true upgrade rather than just a guess.

When applied to financial decision-making—adjusting credit card limits for consumers—we found that this combined approach outperformed traditional models. It wasn’t just about predicting the treatment effect, but also understanding how confident we could be about that effect while balancing it against other possible outcomes.

What makes this important is its broader applicability. Whether it’s deciding a financial policy, optimizing healthcare treatment doses, or managing resources, this refined approach could change how we navigate complex decisions. By blending causal analysis with a richer understanding of uncertainty, we can make recommendations that are not just statistically sound, but also practically more effective and personalized.

Our study is a step towards smarter decision-making in areas where “one size fits all” just doesn’t cut it. This work helps ensure that recommendations, whether in finance, healthcare, or any other field, are optimized not just for an average effect but for the best possible outcome across a range of real-world scenarios.

You can also listen to a machine-generated podcast of the preprint below.



September 23, 2024by Cristian0

I was on the panel once again, for the second time this month (no more until November though!), now discussing the latest inflation numbers and the 50 bps rate cut by the Fed. Like all panels, I got to speak about a couple of other topics too.

  • Rogers acquiring Maple Leafs Sports Entertainment.

With this, Rogers becomes the majority owner of the company, acquiring it from Bell. It gives them one of the most popular platforms for marketing in the country, and in the US as well, increasing brand recognition (through the Raptors). Interestingly, to avoid competition inquiries, Bell will have the option to renew their broadcast agreement at “fair market value”, including 50% content rights for the team’s games. However, this move gives Rogers though a near-complete control of the sports rights in Canada. They already own the Toronto Blue Jays, Rogers Centre and Sportsnet, plus many other investments in teams across the country.

From Bell’s point of view, this eases financial pressures the group has been feeling for a while now, following their plan to streamline operations. Bell wants to focus on tech and comms, nothing else. This deal really showcases the value of Canadian sports teams. The Maple Leafs are the NHL most valuable team, but the Raptors are also the 10th most valuable team in the NBA.

  • Inflation and the Fed Rate Cut

We are seeing that inflation is at a low point now, both in terms of the base-year effect (comparing it to a very high price last year) and momentum in the economy slowing down. Gas is the main reason the CPI has slowed down so much. That one is both seasonal and base-price effect. If you adjust by seasonality, the CPI rose a little bit. The biggest contributors are housing costs (both rents and mortgages). As interest rates are coming down, people on variable rates are having a lower cost, so mortgage costs increases are moderating (“only” 18.8%, coming down from 30.9%), but they are still very high in comparison to a few years ago. Rent costs are still high with no sign of slowing down, which has more to do with landlords passing the higher mortgage costs onto renters, and the very tight housing market we know they are in. Another interesting movement is the drop in clothing and footwear. Normally, August sees price increases, but demand has been very slow for these products, leading to a decrease in prices. Most likely, the lower disposable income that families have is starting to permeate across the economy.

So, what does this mean? It means the economy keeps slowing down, now at a lower pace than even the BoC likes. The question is what does the BoC do in October. There is still one more report on inflation next month, so if we see this slow down is persistent and remains below their target, they may consider giving a boost to the economy, in the form of a 50 bps instead of 25 that the market expects. The last important topic is what the Fed behaviour means for Canada. The BoC started with rate cuts a lot earlier, we are already on our third, so, while there cannot be much disparity between our rates and the US’, we are nowhere near that. We should keep our monetary policy independent of the US’ now. If anything, this supports the BoC decision to start cutting rates early.

  • Tupperware going bust

The company declared Chapter 11 bankruptcy, so this means it will probably not die completely, but restructure and come back in a different form. Tupperware is a multi-level marketing company. These companies depend on the considerable labour force that they have. Over to 465k collaborators worldwide. They make a very limited amount, though, like all MLM companies. The average collaborator (“consultant” as they call it) made US$ 525 per year. The FTC said in 2008 that 99.7% of all consultants lost money when selling their products.

Several factors led to the company’s woes: Their business model not adapting to the 21st century online dynamic, a poor supply chain, and the commoditization of their wares (the moat as it’s so trendy now to say). This even happened as the market for plastic containers has kept growing, it’s just split far more. Over CAD $2b in sales last year. That’s 18% more than before the pandemic. However, competition and the fact that their product is a commodity by now (a Generic Trademark), really impacted their bottom line. After having been acquired in part by private equity, they had to fight being sold in pieces.

To me, this also shows the failure of the MLM business model. Which maybe is a good thing. MLM schemes are not really economically sound business models for the collaborators. There are even internet forums and websites dedicated to calling them out.



September 3, 2024by Cristian0

I got to be at the CBC News’ panel once again this weekend. We discussed three topics:

  1. The Equifax report that showed an increase in arrears in Canadians between 26-35. While the increase is modest, this segment of the population is one of the most vulnerable ones. I don’t think there is any structural issue that would threaten the overall economy, but it does identify a segment of the population that are financially stressed.
  2. Flair Airlines’ $1 base fare. A nice marketing gimmick, that has been shown to increase competition moderately with a 1% to 5% reduction in prices.
  3. LEGO is now aiming to produce 50% of their plastic from recycled materials by 2026, after failing to meet a 100% goal previously stated. Legos were shown to be the most polluting plastic toy, because of the ABS plastic they create their bricks with. These new goals are less ambitious than their previous ones, and show how challenging it is to reduce dependence on plastic. Environmentally conscious consumers will be better serve by using their Legos for longer instead of shopping for recycled ones.

Give a watch to the business panel below. As always, comments are welcome!



July 22, 2024by Cristian0

It’s rare that I get to speak more about the tech side of my Fintech expertise (beyond AI, of course), but with the CrowdStrike bug making a mess around the world, I had the chance to do so on Saturday at CBC and Friday at CTV.

We discussed the impact of this on the financial system, and potential future measures to take given this critical infrastructure’s vulnerability. My take here is that we don’t put the same level of scrutiny to software companies as we do physical infrastructure, even though the consequences of a severe outage of the former can be just as severe. We trust that the companies themselves will have teams that do sufficient quality control. Why? For most critical systems, we require independent verifications. Why not for these companies that supervise, with full privileged access, a big chunk of the corporate systems?

Watch the Weekend Business Panel at the link below!



July 17, 2024by Cristian0

I was asked my opinion on the latest inflation numbers today by Global News. I got to try Western University‘s new studio! Green screen and all.

In summary: Almost in line with what was expected, 2.7% vs 2.8%. There is an 86% chance of a cut next week, but I doubt it will be more than 0.25%, too early to stimuli the economy too much.

The lighting was a bit too strong, so I had to take off my glasses xD. Give it a watch at the link below!

Bank of Canada rate-cut odds rise after June inflation release


Scale-e1720480798699.png?fit=512%2C512&ssl=1

July 8, 2024by Cristian0

This is a bit late, but last month I was very popular after the interest rate decrease by the BoC. Western asked me to write an explainer, which they told me was the most visited article at Western News! I am copying it here for posterity. I also beat a personal record: I had five interviews in 24 hours. It was really a topic that garnished a lot of attention! I appeared in the London Free Press, The X, CHCH News, CFPL News, and Global Radio.

It was great to see that I nailed my prediction too. For July, the rate should remain stable. Too early to tell the consequences of the economy of the very first one. I fully expect a decrease in the September announcement, though. The explainer follows:

Western News: Can Canadians expect an interest rate cut?

Cristián Bravo: Given the latest downward trend on inflation and economic growth (the production of goods and services in an economy), the idea of a rate cut is much more likely. We are seeing a generalized cooling down in the economy that has been persistent over a nine-month period, signalling that the efforts by the Bank of Canada have been successful. The fact that growth is now lower than expected, makes it more likely that the Bank of Canada will decide to ease on their position and start lowering the rate and seeing how the market reacts.

It will need to balance the potential risk of stimulating the economy too early, thus leading to a return of inflation, versus the chance that the slowing growth trend continues, and we enter a recession, as we seemed to have been on the edge of during the last two quarters of 2023.

Why would the Bank of Canada not cut rates?

CB: What may give the Bank of Canada pause are the numbers in the U.S.

The economy there is still in excess demand and inflation has not eased. There has been significant volatility in the core consumer price index and consumption numbers, meaning that not even the Federal Reserve knows the right path to take. This affects us, as the Canadian rate and the U.S. rate cannot diverge too much, or the Canadian dollar will lose value significantly against the U.S. dollar, undoing some of the efforts of the Bank of Canada.

The Bank of Canada does have leeway to lower the rate but needs to be cautious because if the U.S. decides to keep rates high for a while, then we won’t be able to lower them at a higher speed. So, a moderate decrease of 25 basis points (or 0.25 per cent) is likely, although I wouldn’t be surprised if they decide to keep it at its current value and wait until the July meeting to see how the American economy evolves in relation to our own.

What role does inflation play in monetary policy?

CB: Inflation, growth and employment are the trinity of monetary policy. The Bank of Canada controls, through their policy rate, the price of lending money, and this directly controls how much money is available to go around. Too much money related to our capacity to produce goods and services leads to inflation. Too little, leads to a credit crunch and thus decreased growth.

Jobs are directly tied to this. An overheated economy, or an economy without as many workers as needed (as we had a few months ago), leads to inflationary processes, while an economy in depression leads to job losses as businesses need to adapt to the lower demand for their products and services. So, the Bank of Canada’s role is to set the incentives to either stimulate the economy, or to disincentive spending, and this is done by changing the cost of borrowing funds through monetary policy.

What are the benefits of raising or lowering lending rates?

CB: Lower rates mean more incentive to lend money, and thus to invest, hire, spend and produce more. If this is tied to a real need for those goods and services, then growth happens, salaries increase and employment grows. If there is more money than needed in the economy, and we are observing inflation as we were last year, then a higher rate has the opposite effect, disincentivizing spending and demand. The tricky part is reaching a rate that leads to sustainable levels of employment and spending so that we achieve growth and higher salaries while producing goods and services that are aligned with local and global demand.


JetsAwardAAAI.jpg?fit=1200%2C904&ssl=1

March 6, 2024by Cristian0

The Association for the Advancement of Artificial Intelligence (AAAI) conference is recognized as an elite conference in the field of artificial intelligence (AI), gathering a community of academic and industry experts engaged in both theoretical and applied AI research. The 38th AAAI conference was held in the city of Vancouver, Canada, from February 20th to 27th. It offered an excellent opportunity for sharing research work in AI, bridging potential collaborations, and offering the guidance of the direction of AI innovation.

Both Cristian and Jet attended. Jet presented our latest research: “Breaking Barriers: Unveiling Gender Disparities in Corporate Board Career Paths using Deep Learning.” This research was showcased in two workshops: the AI in Finance for Social Impact, organized by J.P. Morgan, and the AI for Financial Services, highlighting the cross-disciplinary impact and relevance of our work. In the former, the lab was also represented in the work “Extreme climate events and credit risk: stress testing approach for loans to SMEs based on network analysis”, presented by the PhD candidate Camilla Carpinelli, part of the group led by Prof. María Óskarsdóttir, at Reykjavík University.

Celebrating Recognition: Best Poster Award

Our collective efforts were recognized with the Best Poster Award at the workshop, a moment of great pride and joy for our team. We extend our deepest gratitude for this honour to the organizers, reaffirming our commitment to contributing meaningful insights and solutions in the realm of AI and social impact in banking.

Networking, Collaboration, and Future Horizons

The AAAI conference provided an excellent opportunity for engagement with the community of AI in Finance. Our team had a great time to meet, network, and exchanging ideas with fellow researchers and practitioners from both academia and industry. Notable interactions included enlightening discussions with peers from prestigious institutions and companies such as CMU, J.P. Morgan, and Capital One, among others.

As we reflect on our experiences at the AAAI conference, we are filled with gratitude for the opportunity to contribute to and partake in the global dialogue on AI. We look forward to attending the next one in 2025!


HouseNetwork-e1707236743536.jpg?fit=200%2C200&ssl=1

February 6, 2024by Cristian0

 

Our latest paper is live! In this work, we study how to model financial contagion over dynamic networks. When people apply for loans, banks have a pretty important decision to make—can the borrower pay it back? Traditionally, banks use credit scores to assess risk, but our new research extends our previous research by delving deeper into the relationships borrowers have with others to better understand their chances of default.

Why Networks Matter in Credit Risk

Imagine you’re considering lending money to someone, but that person is part of a group where others have also borrowed money. This idea is at the heart of our study. Rather than seeing borrowers as isolated, we treat them as part of a bigger network. Their connections to other borrowers—like being in the same neighbourhood or using the same mortgage provider—might influence their financial behaviour.

Predicting Loan Defaults Using Dynamic Networks

Borrowers can be connected in various ways and these relationships evolve over time, making them dynamic. To better capture these connections, we developed a model that combines two powerful tools: Graph Neural Networks (GNNs) and Recurrent Neural Networks (RNNs). The GNNs help us map out these borrower networks, while the RNNs allow us to track how these relationships change over time. But that’s not all—we added an attention mechanism that prioritizes certain time points over others, based on their relevance to the borrower’s default risk.

What Did We Find?

We tested our model using real-world data from Freddie Mac, a major U.S. mortgage financier. The results were exciting—our model did a better job of predicting which borrowers were likely to default compared to traditional methods. It wasn’t just more accurate; it also provided a more profound understanding of why certain borrowers might struggle to repay loans.

Why This Matters

For banks and lenders, this research could change how they think about credit risk. By considering the connections between borrowers, lenders can make more informed decisions. This could even lead to more people getting approved for loans, especially those who might not have had a chance based on traditional credit scores alone. For borrowers, this kind of model could mean more opportunities. If banks can better understand the factors affecting risk, they might be more willing to take a chance on people who were previously overlooked.

What’s Next?

Our research shows that networks play a significant role in financial decisions, and there’s much more to explore. We’re excited to keep building on this work to better understand financial risk. The more we learn, the more we can help lenders and borrowers alike make informed financial decisions.

The paper is available, open to all and with CC-BY license, here. The code to replicate the paper can be found here.

Also, Juan Cristóbal Constain from Quipu created a podcast using NotebookLM from this post and the paper. Give it a listen below if you prefer!


Untitled150x150px4.png?fit=150%2C150&ssl=1

February 4, 2024by Cristian0

A bit late to the party, but as the first paper on this topic was recently published at EJOR (ArXiV, Journal), I thought it may merit the post.

Last year at the credit scoring conference, I was interviewed by Brendan Le Grange, host of the podcast How to Lend Money to Strangers. We discussed the paper I presented there, part of Sherly’s PhD thesis, on causal models for credit limit settings. The preprint of that paper will appear soon, read the first one meanwhile!

If you want to hear more about my thoughts on credit limit setting and how it relates to causal modelling, listen to the podcast episode in this link.



December 1, 2023by Daniel Abib0

We had a great time attending the 2023 INFORMS Annual Meeting that took place between October 15th to October 18th in Phoenix, AZ. This is one of the largest conferences in the field of OR, with 6,000+ attendees and 1,400+ sessions.

The BAL had a strong presence at the conference with four presentations:

  • On October 15th, we had two presentations:
    • Cristián Bravo presented the work with Kamesh Korangi and Christophe Mues on “Large-Scale Portfolio Optimization using Graph Attention Networks”.

 

  • Daniel Abib presented the work with Cristián Bravo, Raffaella Calabrese, and María Óskarsdóttir on “Optimal Feature Split in Classification Models with Dependency”.

 

  • On October 17th, Sahab Zandi presented the work with Kamesh Korangi, María Óskarsdóttir, Christophe Mues, and Cristián Bravo on “Leveraging Dynamic Multilayer Networks for Modelling Credit Risk Contagion in SMEs”.

 

  • On October 18th, Yuhao (Jet) Zhou presented the work with Collins Ntim, María Óskarsdóttir, Matthew Davison, and Cristián Bravo on “Uncovering the Network Power Gap: A Deep Learning Approach to Investigating Gender Disparities in the Boardrooms of Canadian Public Firms”.

 

We also had fun trying a few good restaurants in Scottsdale, AZ!

This was a great chance to showcase the preprints that will come out in the next few months. Stay tuned for them!