Maarten De Ridder
@DeRidderMaarten
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Assistant Professor at @LSEecon - Productivity, (Green) Innovation, Firm Dynamics.
London
Joined April 2009
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Last Seen Profiles
Really pleased that this paper has been accepted. Forever indebted to Vasco Carvalho for being the perfect advisor, to the editor and referees for their time, and for many of you for all the useful conversations and feedback along the way
Forthcoming in the AER: "Market Power and Innovation in the Intangible Economy" by Maarten De Ridder.
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I have the opposite view on this: job market candidates are extremely busy and if the norm becomes that they should tailor their cover letters, it just imposes another common hoop to jump through (that everyone will). Perhaps lets get rid of cover letters instead?
#econjobmarket
#Econjobmarket
— I am really surprised by the significant percentage of cover letters that are completely canned (& even misname the job posting institution etc.) It takes very little effort to tailor a CL to a specific job posting/institution. Given the sheer volume of
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🚨 Call for papers 🚨
CFM / Warwick / Vienna Global Macro Conference
👉 22 and 23 March
👉 At LSE (central london!)
👉 *All macro fields* welcome
Details + submission link here👇
@LSEEcon
@warwickecon
@dandolfa
@farmerrf
@R2Rsquared
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🚨🚨 Call for Papers 🚨🚨
We're organizing the Cambridge Alumni in Macro (CAM) Conference on May 9/10
👉 For anyone with link to Cambridge (UG, PG, fac)
👉 All broad macro fields welcome
👉 Keynote by
@S_Stantcheva
📢Spread the word +submit! (by Jan 12)
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Massive effect: “We exposed students (..) to successful and charismatic women who majored in economics at the same university. The intervention significantly impacted female student’s (..) likelihood to major in economics by 8 percentage points.” -> up from a baseline of just 9%
Gender Differences in the Choice of Major: The Importance of Female Role Models in economics
@AEAjournals
Catherine Porter
Danila Serra
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What is a firm🏙️⁉️
JMP by Lukas (
@_LukasFreund_
@CamEcon
): firms enable people to maximize output by working in teams
Tasks more complex? ➡️people specialize+rely more on colleagues
👉 Talented people team up
👉 Greater inequality across firms
👉 Matches key trends > 1990s
Excited to present my JMP: 𝗦𝘂𝗽𝗲𝗿𝘀𝘁𝗮𝗿 𝗧𝗲𝗮𝗺𝘀!
❓What do firms do? And why are they increasingly important in shaping labor market inequality?
👉This paper highlights the role of specialization, teams & competition for talent.
🔗
👇Summary-🧵
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Dutch evidence from national standardized tests: school pupils (universe of 7-11 yo) learned roughly nothing from 8 weeks of remote teaching in spring, despite NL having highest broadband penetration + efforts to provide techonology if needed
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Exciting conference tomorrow: 14 papers selected out of 300 great submissions for the
@CFMUK
@warwickecon
Vienna Global Macro Conference taking place
@LSEEcon
. Co-organized with Christine Braun,
@farmerrf
@R2Rsquared
@dandolfa
. The program is here:
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🚨🚨 Only 5 days left to submit! 🚨🚨
👉 CFM-Warwick-Vienna Global Macro Conference
👉 All macro submissions welcome
👉 22/23 March, London
@LSEEcon
Accommodation etc will be covered by the organizers✅
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Cool new paper by great
@LSEEcon
PhD students
@gaiagdossi
(JMC!) &
@MorandoMarta
Match USPTO inventor+party registration data ➡️
Dem inventors innovate more in green tech/female health 🌳, GOP inventors in weapons 🚀
Potential impication: inventor prefs push green transition
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Love Hugo's JMP: does technology raise inequality ⁉️
Only if tech is *scale biased*:
👉Fixed-cost tech lowers entry, raises inequality
👉But not all tech raises fixed costs!
Evidence:
👉New historical data (US+NL)
👉Steam: FC⬆️, inequality⬆️
👉Electricity: FC⬇️, inequality⬇️
🚨 I am excited to share my JMP!
"Scale-Biased Technical Change and Inequality"
I propose a new theory on why some technologies increase inequality, while others reduce it. I provide causal evidence from the adoption of steam engines and electric motors to support the theory.
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This is incredible
An amazing *randomized trial* on Twitter+academia:
112 papers were randomly chosen to be shared on twitter by a group with ~58k followers or to not be shared. Papers that were tweeted accumulated 4x more citations compared to non-tweeted papers over 1yr.
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NBER WP by Huiyu Li and
@PeteKlenow
: young firms account for almost 50% of productivity growth, 3x their share in employment. Large/established firms only 10%, much less than their empl. share
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Nice column by
@_LukasFreund_
, Wouter and Pontus on economic uncertainty and unemployment. Highlight: results depend a lot on free entry conditions, so ``despite its popularity, it is perhaps time to drop this free-entry assumption altogether''
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🚨🚨Really great paper by
@_LukasFreund_
. Asks key question: what do firms do? Main insight: firms match complementary co-workers, which matters increasingly as work complexity is rising. Can explain big trends in macro economy, such as polarization of wages across firms 👍
🚨New 📜"Superstar Teams"
🔗
❓Does it matter for the macroeconomy who works with whom?
🔧Model of firm organization + micro data (🇩🇪+🇵🇹)
👉Yes! Importance of coworker interdependencies has ⬆️ & this helps explain⬆️between-firm inequality
👇Summary-🧵
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OBR forecast: pandemic will have 2% permanent scarring effect on UK GDP, mainly because of a shortfall in
#productivity
growth resulting from business failures and lack of innovation and technology adoption -> that's exactly what happened after the global financial crisis
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Who paid the vast majority of development costs for successful vaccines? The public sector!
@billjaneway
@MazzucatoM
Big Pharma says
#Covid_19
vaccines prove how well the system works. For them, yes. But this chart shows that it's public money that did it! On what basis are 'billions of pounds in profits next year' justified?
#Peoplesvaccine
Now!!
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VoxEU column by Cerra, Saxena,
@AntonioFatas
on potentially permanent damage to economy from COVID: "(..) deep recessions have typically led to economic scarring in the long term, what we call hysteresis"
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Fantastic mentoring initiative by PhD students such as
@gaiagdossi
and
@_LukasFreund_
from
@LSEecon
,
@CamEcon
and other top econ departments in the UK
BIG NEWS: We are re-launching
#AMP
, a mentoring program for minority applicants applying (/planning to apply) to Econ PhDs. Apply & spread the word!📣
#econtwitter
@LSEEcon
@CamEcon
@OxfordEconDept
@EconUCL
@warwickecon
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We find a multiplier of 2.4->local income increases 2.4% if Pell grants rise by 1% of income. That's more than other types of spending. Effect is largest in community colleges but small at for-profit schools. Joint with Damjan Pfajfar+Simona Hannon,
#FederalReserve
#EconTwitter
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Spot on blog by
@johnvanreenen
about the mini budget. UK's biggest economic issue is long-term stagnation of productivity growth; not high taxes + lack of gov debt
Why the mini-budget will not give the UK the good growth it desperately needs My analysis of the 'shortest economic suicide note in history'
@jdportes
@ChrisGiles_
@paulkrugman
@sjwrenlewis
@BenChu_
@dsmitheconomics
@RachelReevesMP
@TorstenBell
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New working paper by
@Basile_G
, Burstein & Carvalho (that I RA'ed on for many -enjoyable- hours). Takes a deep dive into markup cyclicality and shows that oligopolistic competition/w strategic interaction can reconsile previous contrasting evidence, with evidence from census data
WP () with
@arielburst
(
@UCLA
) and V.M.Carvalho (
@CambridgeINET
@Cambridge_Uni
). “Bottom-Up Markup Fluctuations”. What drives markup fluctuations? Firm-level shocks, oligopolistic competition and flex prices go a long way to reconcile lingering disagreement
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Great column by
@_LukasFreund_
and Pontus Rendahl explaining why banks do *not* create money out of thin air | VOX, CEPR Policy Portal
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Corsetti et al: letting the infection rise unmitigated could have caused a large contraction in activity because symptomatic infective individuals who would not have been able to work -> activity could have dropped 30%/month.
@CambridgeINET
@voxeu
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including (a very non-exhaustive and twitter-only list)
@billjaneway
@Basile_G
@CoenTeulings
@ben_moll
@R2Rsquared
@_LukasFreund_
@ilzetzki
@JADHazell
@haskelecon
@pontus_rendahl
@C_Criscuolo
@johnvanreenen
and everyone at
@CFMUK
@janewayinst
@ECB_Research
@POID_LSE
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New paper by
@johnvanreenen
, Aghion and Bergeaud show effect of size treshold in labor market regulation on innovation. Results: firms hesitate to make incremental innovations around treshold, but not redical innovations
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Really useful paper by
@matejbajgar
,
@C_Criscuolo
,
@Sara_Calligaris
,
@g_berlingieri
&
@JonathanTimmis
showing when Orbis is a reliable proxy for data on the universe of firms. Conclusion: mainly usable for large firms + limited set of countries, be careful with time variation.
Our new paper
@OECDinnovation
explores coverage and representativeness of a popular firm database Orbis. joint with
@C_Criscuolo
@Sara_Calligaris
@g_berlingieri
@JonathanTimmis
#OECD_PBD
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“Without policy actions, around 30% of European firms would face liquidity shortages after two months of confinement measures”.
@Sara_Calligaris
et al in a new
@voxeu
column:
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"Banks that adopted IT more intensely before the Global Crisis were significantly more resilient when the shock hit." --> Technology adoption in lending can enhance financial stability
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A conversation with
#ChristinaRomer
on macroeconomics, fiscal policy in the
@BarackObama
administration, and recent developments in the U.S. economy:
@CambridgeINET
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Nice column
@voxeu
on the relationship between intangible capital investments and productivity growth. As firms age, intangible investments drop; may explain negative age/growth relationship
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Interested in using cutting-edge research to improve productivity through nurturing innovation, and diffuse these ideas across the economy? Apply for this research assistant role, to work with
@johnvanreenen
@POID_LSE
Closing date: Tue 28 Feb
More info:
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Uncertainty has a negative effect on supply because it raises the risk premium; new column on the macro effects of coronavirus by
@_LukasFreund_
and Pontus Rendahl
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Job market paper by my great coauthor
@MorzentiG
: change in antitrust policy requiring fewer mergers to be reported to authorities caused 30%(!!) decline in patenting activity by firms involved in unreported mergers
Hi
#EconTwitter
! This is my JMP 🧵
🚨 Is lax merger policy bad for innovation? 🚨
I have a natural experiment on a relaxation of pre-merger notification rules. (Spoiler Alert) Horizontal mergers lead to 30% less innovation when they are not notified!
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Really puzzling and striking: like in the USA, there now seems to be an increase (!) in UK business creation compared to last year. Some sectors (retail) and areas (London) have positive cumulative firm creation compared to 2019. Analysis from
@anthonysavagar
@Alfred_Duncan
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UK business creation down 22% since lockdown started. Large decline, but smaller than 42% decline in the USA. Research by
@anthonysavagar
👇
Near real-time analysis of business creation in the UK. Full report:
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Germán Gutiérrez and Sophie Piton
@so_piton
reveal differences in measurements in the labor share across countries: only US has serious decline when measured consistently
Forthcoming in AER: Insights: "Revisiting the Global Decline of the (Non-Housing) Labor Share" by Germán Gutiérrez and Sophie Piton.
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Best of luck to the great candidates from
@CamEcon
on the market this year!
#EconTwitter
The Faculty of Economics is pleased to announce its 2021 Job Market candidates.
A complete list of the candidates can be found here:
Over the next few days, we will introduce each of them with a tweet on their JMP.
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Anyone looking for a last minute RA position/predoc?
@econ_ra
Starting in July!
Thinking about a PhD in Economics but not sure what's involved? I'm hiring for an 11 month full-time Research Assistant to work on research projects studying international trade. Experience with matlab or julia programming preferred.
#EconTwitter
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Measuring the impact of malfunctioning credit markets on productivity | VOX, CEPR Policy Portal
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Hosted and generously supported by
@janewayinst
, and
@CamEcon
. Taking place at
@CaiusCollege
. Co-organized by Margit Reischer and
@splloyd_econ
with great support from
@MeredithCrowle1
. Please RT!
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Fantastic program for the launch of the
@janewayinst
@billjaneway
@CamEcon
, *next tuesday*, will be livestreamed on youtube!
#EconTwitter
Don't miss the *Official Launch* of the Janeway Institute
@CamEcon
next Tues 19th Oct, 4pm-5.45pm! We have a great line-up including:
@helene_rey
,
@JosephEStiglitz
, Hyun Song Shin, A. Schoar. Join us on the live stream here:
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New cool evidence that markups are rising. Interesting finding: ``The change is attributable to decreases in marginal costs that are not passed through (..) in the form of lower prices'', driven by rise of intangibles?👉
@_amackay
@NateHMiller
@JoelStiebale
Evidence on rising markups using detailed product level data: 25% increase between 2006 and 2019
Hendrik Dopper
@_amackay
@NateHMiller
and
@JoelStiebale
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😂😂😂
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This is exactly what people around me remark about research the last months. Eager to get back to work!
Remote work? "Projects take longer. Training is tougher. Workers appear less connected and bosses fear that younger professionals aren’t developing at the same rate as they would in offices, sitting next to colleagues and absorbing how they do their jobs"
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@ArshiaHashemi
@jan_eeckhout
@mmorl89
@ReddingEcon
@FelixTintelnot
@TradeDiversion
@imanelici
@itskhoki
@BrianCAlbrecht
@NateHMiller
@_amackay
@Basile_G
Congrats Arshia - but can you really conclude that revenue-based markups often measure input wedges? That's only the case for mon. competition CES demand. We find that correlations between revenue & true/quantity-based markups are actually high in practice:
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Vasco Carvalho on the new Janeway Institute
@CamEcon
founded by Weslie &
@billjaneway
. ``By contributing to the Janeway Institute, you��re partnering with one of the most venerable and storied Economics departments in the world''
In an interview for alumni of the Faculty of Economics Vasco Carvalho reflects on the success of
@CambridgeINET
.
It will shortly transform into a new institute investing in shaping young minds, transforming economic research & disseminating frontier work.
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Love this new working paper by
@LidaSmitkova
. Countries with competitive firms -> higher markups -> higher savings / CA surplus under financial liberalization. Insightful model with new empirical evidence for Europe.
#EconTwitter
A NEW working paper by
@LidaSmitkova
studies how firm heterogeneity shapes capital flows. Fat tailed firm productivities + oligopolistic competition = high aggregate profits. Disproportional saving out of profits then generates capital outflows. Read here:
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Remarkable: NL consumer confidence is quite stable and much stronger than after Euro crisis. Combined with strong GDP growth and low bankruptcies: evidence that large fiscal expansion was very successful?
Consumenten zijn nog niet erg pessimistisch over hun financiële situatie. Het pessimisme kan in 2021 toenemen, o.a. als cao-loonstijgingen afnemen, terwijl de economie naar verwachting wel verder herstelt. Meer in de
#ING
Outlook 2021:
@klok_marcel
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Dutch domestic card transactions: up from trough of -40% to -5% compared to last year
Hoe gaat het met het herstel van de consumenten-aankopen? Belangrijk daarbij is om niet alleen naar pinbetaling, maar ook naar cash te kijken (in binnen- en buitenland). Dat totaal van pinbetalingen en geldopnames ligt nog altijd 10% lager dan vorig jaar.
#ING
@NLbetalen
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The COVID crisis and productivity growth | VOX, CEPR Policy Portal
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If returns to research diminish over time, short-term disruptions do not have persistent effect on level of output --> there are more ideas in the untapped stock left to be discovered. New note by
@Conor_A_Walsh
👇
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Fiscal multiplier of CARES stimulus transfer could be 2 (!) if recipient is unemployed
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Interesting move by
@Cambridge_Uni
- would be fantastic if this makes it possible to curtail (inevitable) outbreaks among students and help keep the uni open
@Cambridge_Uni
just announced a weekly asymptomatic screening program for
#COVID19
for all students living in college accommodation.
The scheme will rely on a pooling procedure and self-administered tests.
More info in screenshot and the following link:
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@mcecibustamante
@constant_hevia
This article uses Dutch data to show that the initial closure of schools for 8 wks reduced learning outcomes by the equivalent of .... approx 8 weeks of schooling. Despite near-universal broadband availability.
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This is such a cool paper by
@Akash_Raja13
- shows that many savers become active -> inactive -> active again on stock market, casting doubt over common explanations for low participation on stock markets
#EconTwitter
#Econjobmarket
and
#EconTwitter
, have a look at
@Akash_Raja13
's research: on the job market from
@LSEEcon
. His research is in macro/macro-finance/household finance.
He has an excellent job market paper on the dynamics of stock market participation.
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This would be such a shame
/1. Yesterday at the ACS Data Users Conference, the Census Bureau described its plans to replace the American Community Survey (ACS) microdata with “fully synthetic” data over the next three years.
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@florianederer
If it's anything like the boat race, probably substantially later than our conference! 😁
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@porszag
@bopinion
This is not a contradiction. Superstar firms -despite initially bringing higher productivity growth- can still harm innovation and deter entry when they consolidate their position and use cost advantage to undercut competitors. See
#antitrust
@ThomasPHI2
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💪 Lukas has already published 2 JMEs, an RED. And posts the best twitter paper sumaries 😉
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Great initiative!
Some news I'm really excited about 🥳: with 30 other PhD students in Economics at LSE, we have launched a mentoring programme for PhD applicants from underrepresented backgrounds.
The programme is called AMP:
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VoxEU column by Bonadio et al. that quantifies the % of GDP reductions from COVID due to intl supply linkages. Main result: model predicts 30% decline in GDP on avg, with 1/3 driven by intl linkages/spillovers.
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Productivity growth in the intangible economy | VOX, CEPR Policy Portal
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Very straightforward and insightful paper by
@itskhoki
and my fantastic colleague
@MukhinDA
. Sanctions on Russia that prevent imports may over time cause appreciation of
#Ruble
, consistent with pattern since the start of the invasion of Ukraine
For anyone who wants to know why the Ruble does not fall:
Oleg Itskhoki and Dmitry Mukhin - Sanctions and the Exchange Rate - NBER Working Paper no. 30009:
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Q1 economic growth vs lockdown intensity, by
@INGnl_Economie
German and Dutch GDP growth confirm that Q1 was all about those last two weeks of domestic lockdown. Eurozone 2nd estimate in under an hour, curious to see if we get any revisions to the average or one of the big countries that released figures early.
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Corsetti et al. from
@CambridgeINET
: concessional loans during the euro crisis reduce the need for severe austerity policies during a deep recession.
📃 New paper by Corsetti (
@gc422
,
@Cambridge_Uni
), Erce & Uy (2020)
👉 Review official sector lending during the €-area crisis: stylised facts, effects on market access, implications for policy design
🔗
👇 A few key points
#EconTwitter
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@EconTraina
@ArshiaHashemi
@jan_eeckhout
@mmorl89
@ReddingEcon
@FelixTintelnot
@TradeDiversion
@imanelici
@itskhoki
@BrianCAlbrecht
@NateHMiller
@_amackay
@Basile_G
No, revenue data still allows you to estimate markups. The only thing you miss is the average markup. That's why CES is knife edge: the avg is everyone's markup. Generally markups from revenue data are v informative of true markups. We show this analytically and with simulations.
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@Sywert
Mogelijk antwoord hier: In het kort: jonge en oude mensen wonen veel vaker samen in Italie
@christianbaye13
& me have been thinking about the big differences in mortality rates so far during the corona outbreak in Europe. The differences in case-fatality rates are humongous. Italy has one of 6% while countries like Norway, Denmark & Germany have rates still close to 0.
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@TomValletti
Is this really news? Plan is to introduce roaming charges for usage above 25GB (!!)... Vodafone has had that as a `fair use' limit on roaming for a long time. And even within the EU, providers can charge for excessive roaming outside of the home market
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@_LukasFreund_
@arthurturrell
It's a layer of gel between the inside and the outside window of the plane!
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@MarynBolhuis
@sharatganapati
Non-rivalrous yet excludable (therefore raising fixed costs, lowering marginal costs) is one way to think about intangibles - see my voxeu column:
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The UK productivity puzzle: CFM survey | VOX, CEPR Policy Portal
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@bankofengland
@haskelecon
@UoNEconomics
@UniofNottingham
Thanks for the mention
@bankofengland
@haskelecon
!
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Nice thread by
@R2Rsquared
on
#MMT
. Like the proposal to rename it `new fiscal activism'!
** MMT is the new supply-side economics
Forty years ago, some economists started from an uncontroversial (but important) result: a lower tax rate raises the tax base, so revenues won't fall as much. But then they ran with it, predicting tax rate cuts could raise revenues.
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@XJaravel
and O'Connell show that inflation of groceries was 2.4% in the UK at start of lockdown (10x usual rate), mainly because of lack of discounts. Temporary boost in demand because of hoarding?
[1/N] What happened to inflation during the lockdown? Our new paper is out, using scanner data covering millions of transactions for fast-moving consumer goods in the United Kingdom.
@TheIFS
@STICERD_LSE
@CEP_LSE
Paper is here:
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