Cristian

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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.



May 27, 2024by Cristian0

A new panel is live, and now we are featured on the CBC website! This time we spoke about three topics:

  1. The DoJ suing to split back Ticketmaster / Live Nation: The most significant change versus previous attempts is that now they managed to get everyone angry. Artists, venues and consumers are all affected. Oddly, due to weak antitrust laws in the US, consumers are not considered direct customers of Ticketmaster, so now that artists and venues are shown to be affected, the DoJ could intervene. If successful, this should increase competition in the artist/venue space, not in the consumer one, so don’t expect ticket prices to come down anytime soon.
  2. The new low fare from WestJet: WestJet is moving towards an Ultra Low-Cost Carrier (ULCC) model, charging now for the carry-on baggage. This is common in European ULCC, such as EasyJet and others. Changes like this are great for the company as they save on fuel, save on airport fees and taxes, and provide marginally better customer service to those who require overhead bins as there is less demand for them. It also comes with a modest 2% decrease in fares in competitive routes. However, the cost is more fare dispersion. Now you won’t really know what the final price of your ticket will be, and you will need to plan a bit ahead to what you want to bring with you. Also, airports may need to rethink their fee structure, considering they are normally tied to the base price of the ticket.
  3. Inflation: The latest inflation numbers were positive for Canada, with a 2.7% annualized rate. However, and what I spoke about in the panel, I expect the BoC will be a bit wary of being too aggressive lowering the interest rate, given the US is still suffering high inflation and the rates between the two countries cannot diverge too much.

Give it a watch and comments always welcome!


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April 1, 2024by Cristian0

I was at the CBC News’ Weekend Business Panel this week, speaking about some interesting news that happened. Sadly, the CBC changed their policies, and now we don’t get a video of our participation, so I will be publishing these short summaries after every time I appear. This week we spoke of:

  • The MLS judgment in the US that may change the incentive structure of realtors: Looking at this from a pure incentive structure, the realtor business is poorly constructed. The buyer pays commission to their realtor based on a percentage of the purchase price, which means there are no economic incentives for their realtor to get them their best price (although they do have a fiduciary duty).
    • The lawsuit in the US will change the structure of the process. It will now require a contract between the realtor and the buyer directly, with agreed fees, before showing houses. Buyer representation agreements are already common in Canada, this lawsuit splits the buyer and the seller’s commission, thus providing incentives to realtors to lower their fees when representing the buyer.
      • There is a new rule prohibiting offers of broker compensation on the MLS, and from creating rules that would permit a seller’s agent to determine compensation for a buyer’s agent.
      • However, this also means homebuyers will have to consider an extra closing price, instead of the now baked into the mortgage fee. Fees should come down but will also need to be paid up front.
      • In the US, the realty companies are saying they will not change their practices, as nothing in the judgment forces them to. There is a difference in interpretation on what the judgment actually means. This will most likely lead to new lawsuits if the actual implementations differ for what the other side interpreted.
  • Home Depot’s acquisition of building material supplier SRS Distribution. Home Depot’s thinking is that growth will come from contractors as opposed to retail, that boomed during the pandemic and is now coming down. Their bet is that construction of new homes and government plans to stimulate construction in general will mean higher sales than what they are seeing in their stores.
    • Home Depot said that when taking the deal into account, it now believes its total addressable market is approximately $1 trillion, an increase of approximately $50 billion. Home Depot controls 17% of the market.
    • One pain point in Home Depot has always been logistics, one of SRS’ strengths with their warehouses and truck fleet. This can bring synergies into their main business, even though SRS will continue operating as an independent entity. Through the deal, expected to close by the end of fiscal 2024, Home Depot will add SRS’ network of more than 2,500 professional sales force in 760 plus locations to its footprint of over 2,000 U.S. stores and distribution centres. It would also allow Home Depot to take advantage of SRS’ more than 4,000 truck fleet and job site delivery capabilities.
    • There is still regulatory approval necessary. I am sure Lowe’s will have something to say about this deal. Maybe I’ll get to talk about this later again.
  • Cocoa prices have reached their highest value ever, hitting USD $10,000 per tonne. This is caused by a multifaceted problem. Short term: El Niño and West Africa pests, the swollen-shoot virus and black-pod disease, have been causing havoc with plantations. Just the Swollen-shoot virus affected 20% of all cocoa trees in the Ivory Coast. The war in Ukraine has also caused the sugar prices to go up, thus impacting further the price of chocolate.
    • Long term, though, there is a geopolitical issue. Farmers get about 5% of the price of a bar, or 30% – 50% of the price of a tonne of cocoa. Each producer can make around 1 tonne per year, thus the income of a farmer is around USD $5,000 yearly at best. This has lead to unsustainable practices. 14% of the Ivory Coast and 11.5% of Ghana are cocoa plantations and many are planted in protected areas, 37% of the Ivory Coast and 13% of Ghana’s deforestation comes from cocoa planting.
    • Any solution is super complex. As hard as solving hunger in Africa.  Only a mixture of better governments, better access to sustainable farming training and supplies, less corruption, more development and a strong coordination between governments and international agencies can tackle this. Sadly, to me, this hints we won’t see chocolate prices come down anytime soon, and if the underlying issues are not resolved, we will end up with chocolate scarcity in the long term.

Happy to hear your thoughts about this. I’ll be again next time in May. Always a fun experience!


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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!


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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!


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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.



October 6, 2023by Cristian0

We had a great time attending the Credit Scoring and Credit Control Conference XVIII that took place between August 30th to September 1st in Edinburgh, UK. This conference bridges the academic/practitioner divide and is the world’s premier conference for credit scoring and credit risk related topics.

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

  • On August 30th, Cristián presented the work with our PhD student Mahsa Tavakoli, cosupervised by Rohitash Chandra from UNSW, on “Multi-Modal Deep Learning for Midcap Credit Rating Prediction Using Text and Numerical Data”.
  • On August 31st we had two presentations:
    • Our collaborator Prof. María Óskarsdóttir from Reykjavík University, Iceland, presented the work by our PhD students Sahab Zandi and Kamesh Korangi, cosupervised by Prof. Christophe Mues from Southampton University and Cristián, titled “Credit Scoring with Dynamic Multilayer Graph Neural Networks”.
    • Cristián presented the work led by our PhD student Sherly Alfonso Sánchez, cosupervised by Prof. Kristina Sendova here at Western, called “Causal Learning for Credit Limit Adjustment in Revolving Lending Under Adversarial Goals”.
  • On September 1st, we had three:
    • Daniel Abib, who joined earlier this year as a postdoc at the Lab, presented the work coauthored with Prof. Raffaella Calabrese for Edinburgh University, Prof. María Óskarsdóttir, and Cristián. The work was called “Optimal Feature Split in Credit Risk Models with Dependency”.
    • Our PhD student Kamesh Korangi presented the work from his PhD, coauthored with Christophe Mues and Cristián, on “Deep Temporal Graph Networks for Behavioural Scoring Prediction in Revolving Credit Lines”.
    • Our PhD student Sahab Zandi presented the work with coautored with Kamesh, and cosupervised by Prof. María Óskarsdóttir, Prof. Christophe Mues, and Cristián. These last two works are part of the collaboration with one of the largest consumer banks in the world. Sahab’s presentation is titled “Modelling Credit Risk Contagion for SMEs over Supply Chains using Dynamic Multilayer Networks”.

The conference provided a great opportunity to meet and network with people in the field of credit risk from both academia and industry. We were honestly surprised and happy with the reception that we had from the conference attendants. We had many interesting talks and we look forward to what will come out of these chats!

We also had a blast having a reunion with some friends and colleagues after a while in Edinburgh!

We would like to thank the organizers, Professor Galina Andreeva and Professor Jonathan Crook from the Credit Research Centre at the University of Edinburgh, plus of course our collaborator Prof. Christophe Mues for hosting this wonderful conference. We look forward to attending the next one in 2025!

 



September 25, 2023by Cristian0

Now that the summer is over I was invited once again to the Weekend Business panel on CBC News. You can watch it below!

The TL;DW version is:

  • Latest inflation numbers: Not very good news as inflation seems to be supply-side, so it is much harder to control. Gas prices will also negatively affect the price of food even more for the next quarter at least. This means that interest rates will remain high for a while, possibly even into 2025. Also, deflation is not a bad thing if it is transitory and aimed at first necessity goods, as opposed to affecting consumption in the long run.
  • The UAW strike: Not really my topic, but my comment here was that the strike was expanded significantly and that can impact car prices in the future as it will now target in-demand cars. Also, some factories in Canada may be facing temporary work stoppages. 
  • Equifax report on the increase in lending application fraud: while this is a relatively minor issue, it mixes two different things. First, mortgage fraud is on the rise. Most of this type of fraud is misrepresentation of income, which may be considered a white lie by some borrowers (16% according to a relatively old survey), but it actually is fraud and can have serious consequences for borrowers. The second is auto and credit card fraud. This one is mostly done by criminals that steal identities. The recommendation here is clear: monitor your credit at least monthly and if you see anything that you don’t recognize, immediately contact your financial institution.

I’m on next on October 14 and November 4.



August 15, 2023by Cristian0

I had a great time presenting a keynote and a paper at the SIGKDD 2023, one of the elite conference in computer science. In my personal opinion, the KDD is the top applied data science conference, as NeurIPS is a bit too theoretical, while the KDD is a bit more integrative. Lots of papers this year in network science and causal learning, which was encouraging when evaluating the current research lines of the group.

I presented two works in the Machine Learning in Finance workshop of the conference:

  • The keynote “Leveraging Deep Learning for Multimodal Data Analysis in Credit Risk Assessment“, where I summarized the latest work of the lab in using multimodal data for the analysis of credit risk in midcaps and retail lending. I presented results of our latest preprints (paper on midcapspaper on mortgages) and preliminary results on using LiDAR for mortgage analysis and social network analysis for credit risk modelling. I shared the stage again with three other keynotes from Bloomberg and Blackrock, the same groups that presented in the Columbia-Bloomberg seminar in May we also presented in, and with Srijan Kumar from Georgiatech. Srijan was keynote in the NeurIPS workshop we presented our paper on influencer detection (NeurIPS paper, journal preprint). The machine learning in finance world seems to be pretty small!
  • The paper “Graph Attention Networks for Portfolio Optimisation: Empirical Evidence for Mid-Caps” by our PhD student Kamesh Korangi. Kamesh couldn’t attend as the US visas are taking forever. In this talk I showed the preliminary results of our work on using GATs for optimizing portfolios. We are really excited about this work! I can’t wait to show the world about in the near future. Stand by for the preprint, it should be available in a few months. The presentation itself will be available in a few weeks, I’ll update this post when it is.

It was a fantastic experience to attend the KDD in person. Sadly, we weren’t able to do so in 2020 due to the pandemic, where we presented the preliminary results of our paper in default propagation across multilayer networks (KDD paper, YouTube video with the presentation at CORS 2021, extended journal paper). It was great to be able to present now and share with so many top researchers.

The conference was in Long Beach, so I also got to have some great weather.

Cristian in front of the sunny Long Beach Convention Center

The acceptance rate of the conference was higher than previous years, around 20%. However, the MLF workshop was even more selective with only around 10% of the papers being selected for spotlight talks! It was great to be in such an exclusive group.

Slide with the acceptance rate of the KDD conference per areas. Finance is 22%.

Also, it was great to see so many Latin Americans there! We had a few meetings and even some went salsa dancing. We were very pleased to also meet with Ricardo Baeza-Yates, a legend in the field.

Latin Americans sharing a lunch at the KDD.

Overall, it was a great experience. Hopefully we’ll be able to attend to KDD 2024 in Barcelona!