1 First steps in practice Daniel Mouqué Evaluation Unit DG REGIO.

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First steps in practice

Daniel MouquéEvaluation Unit

DG REGIO

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The story so far…

• Indicators useful for management, accountability, but do not give impacts

• For impacts, need to estimate a counterfactual

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Notice that « classic » methods often imply counterfactuals

• Indicators – before vs after• Indicators – with « treatment » vs without• Qualitative methods – expert opinion• Beneficiary surveys – beneficiary opinion• Macromodels – model includes a baseline

But all of these have strong assumptions, often implicit

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How to weaken the assumptions…

… and improve the estimation of impacts

Comparison of similar assisted and non-assisted units (finding « twins »)

There are various ways to do this - let’s start with a simple example

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Training for long term unemployed

• Innovative training for those who have been out of work for >12 months

• « Classic » evaluation: for those trained, pre-post comparison of employment status, income

What’s wrong with this?

• So we combine with a beneficiary surveyIs this much better?

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A simple counterfactual(random assignment)

• 10,000 candidates for the training, randomly assign 5000 to training/5000 to traditional support

• Compare employment status and earnings one year after training

• What’s useful about this?• Can you see any potential problems?

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Let’s try again(« discontinuity design »)

• Offer the training to all• For evaluation, compare a subset of these

with a similar, but non-eligible group:– Unemployed for 12-15 months (eligible)– Unemployed for 9-12 months (not eligible)

• What’s better about this than the previous evaluation example?

• What’s worse?

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3rd time lucky (« pipeline »)

• This time we stagger the training over 2 years

• 5000 are randomly chosen to take the training this year, 5000 next year

• Next year’s treatment group is this year’s control group

• What’s good about this?• What limitations can you see?

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Some observations

Notice:• This is not just one method, but a family of

methods• Two families in fact - we’ll come back to this• Different possibilities have different

strengths & weaknesses, therefore different applications

• Varies from simple to very complicated• We’ll look at common features and

requirements now (with Kai)

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What do we need?

Kai StryczynskiEvaluation Unit

DG REGIO

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The methods require

• Large « n », ie a large number of similar units (to avoid random differences)

• Good data for treated and non-treated units– Basic data (who are the beneficiaries?)– Target variables (what is policy trying to

change?)– Descriptive variables (eg to help us find

matches)– Ability to match the various datasets

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Sectoral applicabilityGood candidates (large « n ») include: • Enterprise support (including R&D)• Labour market and training measures• Other support to individuals (eg social)

But…. only where good data exist

Bad candidates (small « n ») include:• Large infrastructure (transport, waste

water etc)• Networks (eg regional innovation systems)

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Rule of thumb

< 50% of cases applicableof which

< 50% have enough data

And even then, be selective. It’s a powerful learning tool, but can be hard work &

expensive.

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A pragmatic strategy

• 2 pronged approach (monitor all, evaluation for a selection)

• CIE where can, classic methods where can’t (survey better than nothing)

• Mix methods (triangulate, qualitative to explain CIE results)

• Be honest and humble about what we know... And don’t know

• Use working hypotheses, build picture over time

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Let’s get started

Daniel MouquéEvaluation Unit

DG REGIO

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The options

There are many options…

…. But two broad families of counterfactual impact evaluation

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Experimental methods Quasi-experimental methods

Eg random assignment, pipeline

Eg Alberto’s difference in difference, my discontinuity

From the outset, some form of random assignment – evaluation drives selection process

Selection process as normal – does not interfere with policy process

Must be installed from the outset of the measure

Can be conducted ex post (although earlier better, for data collection)

Weakest assumptions, best estimate of impact

Relatively weak assumptions, can usually be considered a good estimate of impact

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A « rule of thumb »

• Randomised/experimental methods most likely to be useful for:– Pilot projects– Different treatment options (especially genuine

policy choices, such as grants vs loans)

• Quasi-experimental – more generally applicable

• However, randomised simpler, so a good introduction (Quasi-experimental methods in depth tomorrow)

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New friends part 1Experimental (« randomised »)

methods

Some experimental/randomised options for your exercises in the group work:

• Random assignment• Pipeline (delaying treatment for some)• Random encouragement

Tip: most costly (mess with selection process), but most reliable

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New friends part 2Quasi-experimental methods

• You don’t need to know all these yet (tomorrow will treat in depth

• Intuition: treat as usual, compare with similar, but not quite comparable, treated units

• Difference-in-difference• Discontinuity design (comparing « just

qualified for treatment » with « just missed it »)

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In your group work, we want you to start thinking

• What are policy/impact questions in my field(s)?

• Can I randomise from the beginning, to get an insight into these results?

• Random or not (and often the answer will be not!) can I get outcome data for similar non-treated units?

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To clarify, a real example (from enterprise support)

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The set-up

• Eastern Germany• Investment and R&D grants to firms• Really increases investment, employment?• Could not randomise (too late, too political)• Clever matching procedures (we’ll tell you

more later in the course) to compare similar assisted/non-assisted firms

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The results

• Investment grants of €8k/employee led to estimated extra investment of €11-12k

• Same grants led to an extra 25-30,000 extra jobs

• R&D grants of €8k/employee led to €8k extra investment

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What does this tell us?This gives comfort to the views:

• Enterprise and R&D grants work in lagging regions (at the very least, generate private investment)

• Grants have a bigger effect on productivity than on jobs

• Gross jobs - especially jobs safeguarded - overstate case

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What does this not tell us?We still do not know for certain:• If same pattern would hold outside E. Germany

(specific situation, specific selection process)• If investment will translate into long term growth

and R&D (but have weakened assumption)• If other instruments better than grants• Crowding out in other enterprises• How to cure cancer (astonishingly, 1 study did not

crack all the secrets of the universe)

But know more than before, and this is not the last evaluation we will ever do

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Potential benefits - motivation for the coming

days• Learning what works, by how much (typically)• Learning what instrument is appropriate in a

given situation (eg grants or advice to enterprise)

• Learning on whom to target assistance (« stratification », eg target training measure on the group most likely to benefit)

• Building up a picture over time