Joint Complementarity of Scale and Verification Intermediaries

In Simple Words

Think of a lock that requires two different keys inserted at the exact same moment to open. Turn Key A (advertising) alone and you get a massive line outside your door, but you lock the deadbolt out of fear. Turn Key B (a badge inspector) alone and you have a secure door, but no one is standing in line. Turning both keys together lets employers invite screened candidates inside and complete the hire.

Research question

Digital platforms often fail to drive adoption when they solve candidate reach without providing verification tools for employer risk management. Employers encounter high friction when evaluating unfamiliar candidates outside established social networks.

Participants

1,719 job postings across 1,576 urban firms in Bengaluru, India.

Study Design

Field RCT testing individual versus joint promotional advertising and third-party government ID verification services with administrative data tracking and 6-month follow-up surveys.

Results

The joint treatment increased employer-initiated candidate contact by 147% (from 2.5 to 6.2 candidates) and increased interview likelihood by 25% (13 percentage points). Jointly treated firms were 8 percentage points (68%) more likely to hire from the portal and 11 percentage points (73%) more likely to retain the portal hire after 6 months.

Takeaway

Bundle visibility-boosting advertisements with verified background or ID documentation when launching digital labor platform services for small and medium enterprises.

Read alongside the research

Plain-English glossary

Original explanations, informed by the references below. Examples are illustrations, not data from the studies above. The research text stays unchanged.

Follow-up

Collecting more information about participants later in a study to see what has happened to them. The term can also mean the length of time researchers keep track of them.

ExampleResearchers interview the same workers three months after a programme ends. That later interview is a follow-up.

GET-IT glossary · Follow-up ↗Read more about follow-up →

Percentage points

The difference between two percentages.

ExampleA rise from 40% to 50% is 10 percentage points. Relative to the starting value, that is a 25% increase.

Office for National Statistics · Percentages ↗Read more about percentage points →

Randomized controlled trial

A study that uses chance, like drawing lots, to decide who receives each option being compared. Researchers compare the groups’ outcomes to estimate the effect of those options.

ExampleA lottery assigns volunteers to a training programme or a comparison group. Researchers then compare their outcomes.

GET-IT glossary · Randomized study ↗Read more about randomized controlled trial →

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• Ability-Heterogeneous Wage Returns →Labour & employment

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• Activation Program Threat Effect →Labour & employment

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• Actual vs. Potential Experience Bias →Labour & employment

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