Meet our PhD students

Edvin Ahlander

Year of admission: 2023
Main supervisor: Per Krusell

Project

Do capacity constraints affect the pass-through of monetary policy to prices? (with Niklas Amberg and Mathias Klein, both Sveriges Riksbank)

The post-Covid inflation surge has highlighted the need for a better understanding of price setting behavior. One factor that could influence pricing is capacity constraints, defined as restrictions on firms’ ability to expand production in the short term. These could, for instance, arise from supply chain bottlenecks, which was a prominent feature of the recent inflationary episode.

Using granular Swedish micro data on prices and capacity, we find that capacity constrained firms raise prices more following an expansionary monetary policy shock, but only if a large fraction of their closest competitors are also constrained. Incorporating this aspect of firm behavior into an otherwise standard macroeconomic model elevates inflation when the share of constrained firms suddenly increases, which was the case during 2021–2022. Thus, the model can explain the sudden shift from a low- to high-inflation environment observed during this period.

Tiago Bernardino

Year of admission: 2020
Main supervisor: Kurt Mitman

Project

Over the past 50 years, the U.S. economy has gradually shifted away from producing goods toward providing services. This paper shows that this long-term shift has made the Federal Reserve's interest rate decisions more powerful than they used to be.

The reason is simple: the prices of services change less often than the prices of goods. So as services make up a larger share of the economy, overall prices become ”stickier” and slower to adjust. When the Fed raises or lowers interest rates, this stickiness amplifies the short-term impact on the economy by about 21% compared to the 1970s.

The same mechanism works in reverse for supply disruptions (like oil shocks or pandemic-related shortages): because services are less price-volatile, today's economy absorbs these shocks with smaller price swings than it once did.

Sante Carbone

Year of admission: 2022
Main supervisor: Daniel Buncic

Project

How do climate policies shape FDI? Using data on the subsidiaries of multinational manufacturers worldwide, we show that firms reduce investment in countries with stricter climate rules, and particularly so in countries hosting subsidiaries in highly polluting industries.

When climate policies tighten unexpectedly, multinationals shrink their operations in advanced economies, both in capital and employment, while expanding their subsidiaries in emerging economies with looser regulations. However, the total emissions reported by these multinationals at the group level do not fall: pollution appears to be relocated rather than genuinely reduced, raising concerns about the environmental effectiveness of unilateral climate policy.

Chloé Castagnet

Year of admission: 2022
Main supervisor: Martin Flodén

Project

When a central bank raises the policy rate, the transmission to the broader economy depends in part on how banks set the deposit rates they pay out to their customers. Banks that face little or no competition can keep rates relatively low: this makes deposits cheaper for them but might push depositors to place their money elsewhere.

I study this question in the Swedish context and find that when the Riksbank raises the policy rate, deposits flow out of the banks that compress their rates, and into the banks that offer more competitive terms. I also find evidence of internal reallocation, as depositors shift from sight to time deposits within the same bank when rates on the latter are much more attractive. Currently, I am investigating whether these deposit shifts affect the banks’ ability to lend.

Martina Dosser

Year of admission: 2020
Main supervisor: Per Krusell

Project

I develop a heterogeneous-agent model with banking competition to study the implications of wealth heterogeneity for the rate-setting behavior of banks. This novel framework establishes a link between a bank’s market power and the wealth composition of a bank’s customer base.

A depositor’s wealth determines her incentive to react to rate changes by adjusting her savings, on the one hand, and switching banks or savings instrument, on the other. I study how the resulting heterogeneity in deposit supply elasticity affects banking competition and the pass-through of monetary policy.

Sofia Giovannetti

Year of admission: 2021
Main supervisor: Per Krusell

Project

Passive investment and firm innovation (with Timo Boppart, Per Krusell, Kieran Larkin, and Kurt Mitman)

Over recent decades, more and more people have moved their savings into index funds – investment products that automatically track the market rather than picking individual stocks. This project asks: what happens to companies and the broader economy when so much money is invested this way?

Using an economic model, we study how the rise of so-called passive investing affects stock prices and whether firms are incentivized to innovate and grow. This matters for central banks because the way financial markets work influences how effectively interest rate decisions feed through to business investment and to the economy as a whole.

Jacob Granqvist

Year of admission: 2023
Main supervisor: Martin Flodén

Project

Dissent in central bank communication

I study how disagreements among decision-makers at Sweden’s central bank, the Riksbank, influence the economy. I’ve collected detailed records of what these policymakers say during the meetings, which lets me look closely at how they communicate.

I then examine whether their disagreements affect financial markets and the wider economy. My early findings suggest that these disagreements can have some short-term impact, but they don’t seem to matter much in the long run.

Arien Haghshenas

Year of admission: 2023
Main supervisor: Gustav Martinsson

Project

Machine learning forecasts randomness due to seed choice

Many machine learning methods involve randomness when they are trained. Researchers often fix one random seed so the results can be reproduced, but this paper shows that the chosen seed can materially change the conclusions. Using stock-return prediction as the setting, I train the same models many times with different seeds while keeping everything else unchanged.

The resulting portfolios can hold different stocks, earn different returns, and lead to different claims about whether a model works. The main message is simple, one run of a random machine learning model is not enough. Researchers should show how results vary across seeds.

Nils Landén Mammos

Year of admission: 2019
Main supervisor: Roine Vestman

Project

The bank of mom and dad: intergenerational transfers and macroprudential regulation

Mortgage rules are meant to stop homebuyers from taking on too much risk, but they do not affect everyone in the same way. Using detailed Swedish records, this paper shows that some parents borrow against their own homes to help their children make down payments. These children can buy more expensive homes while still meeting mortgage rules, though they often end up with more debt relative their income.

Evidence from Sweden’s 2010 mortgage cap shows that this policy had less bite for buyers receiving support from parents, showing that access to parental wealth can shape the effects of mortgage regulation.

Dario Luciani

Year of admission: 2022
Main supervisor: Ai Jun Hou

Project

We study the effect of monetary policy on households’ allocation of their financial wealth. Using administrative data covering the full Swedish population, we show that an increase in the monetary policy rate lowers the share of financial wealth invested in risky asset.

Moreover, we find that this effect varies systematically with the risk properties of labor income. Households whose labor income risk is more correlated with the aggregate economic activity adjust their financial portfolios less following a change of the monetary policy rate.

Isabella Maassen

Year of admission: 2021
Main supervisor: Timo Boppart

Project

Savings, Entrepreneurship and Innovation (with Sofia Giovannetti)

We use detailed data from Sweden to study how differences in family wealth affect who starts a business and how well those businesses do. It looks at whether people from wealthier families are more likely to become entrepreneurs, and whether this gives them an advantage even when others might have equally good ideas.

The project also examines how these differences can lead to lost economic potential when talented people are held back simply because they lack financial resources.

Kianoush Saeedi

Year of admission: 2023
Main supervisor: Roine Vestman

Project

This project studies how mortgage market regulations interact with interest rate policy to shape the broader economy, with a focus on Sweden’s highly indebted households and predominantly floating rate mortgages. When interest rates change, many Swedish households feel the effects immediately through their mortgage payments, which can strongly influence their spending. Policymakers worry less about mortgage defaults and more about the possibility that heavily indebted households sharply cut consumption in downturns, amplifying recessions.

To understand these dynamics, I build a quantitative economic model that captures how different types of households make decisions about housing, borrowing, and spending under various mortgage regulations. This framework allows me to evaluate how policies like loan to value limits or amortization requirements affect the transmission of monetary policy and to explore how coordinated policy design can support both financial stability and intended macroeconomic outputs.

Hedda Thorell

Year of admission: 2021
Main supervisor: Roine Vestman

Projects

Quantitative Easing and Portfolio Rebalancing: Evidence from a Small Open Economy

Who sells to the central bank during QE, and how are the proceeds reinvested? I study the Riksbank's QE programme during the Covid pandemic, a purchasing programme targeting Swedish covered bonds. I find that the purchases lowered yields and that Swedish investors used the proceeds from their sales to buy government bonds. By contrast, foreign investors did not reinvest their proceeds within the Swedish market, but instead paid back loans that had been used to finance their purchases.

The Macroeconomic Consequences of Undermining Central Bank Independence: Evidence from Governor Transitions

What are the macroeconomic consequences of undermining central bank independence? Using novel data on central bank governor transitions across countries, we find that when political pressure drives these appointments, it is often followed by lower rates and a short-term boost to growth. But when governments install governors who reject conventional monetary frameworks, the downsides manifest over time in the form of higher inflation and eroded credibility.

João Quelhas

Year of admission: 2024
Main supervisor: Kieran Larkin

Project

We study how public knowledge of a firm’s quality can unlock access to credit and boost the wider economy. Using data from Portugal, we examine three strong signals of quality: winning a public contract, receiving a grant, or obtaining official certification. After these events, firms borrow more, pay lower interest rates, default less, and depend less on a single bank.

We find similar results in the United States. We then build an economic model showing that when lenders have better information, credit flows more easily to stronger firms, raising productivity and improving overall economic performance.