Table 1.

Elementary indicators of public contract corruption risk. More detail is provided in the electronic supplementary material.

indicator and symbol	values	indicator definition
single bidder Csinglebid	{0, 1}	1 if a single firm submits an offer.
closed procedure Cclosedproc	{0, 1}	1 if the contract was awarded directly to a firm or by invite-only competition.
no call for bids Cnocall	{0, 1}	1 if no call for bids was published in the official procurement journal.
long eligibility criteria Celigcrit	{0, 1}	1 if the length in characters of the eligibility criteria for firms to participate in the tender is above the market average.a
extreme decision period Cdecidetime	{0, 1}	1 if the award was made within 5 days of the deadline or more than 100 days following.
short time to submit bids Cbidtime	{0, 0.5, 1}	1 if the number of days between the call and submission deadline is less than 5, 0.5 if between 5 and 15.
non-price criteria Cnonprice	{0, 1}	1 if non-price criteria are used to evaluate bids.
call for bids modified Ccallmod	{0, 1}	1 if the call for bids was modified.

^aWe define a market in terms of two-digit common procurement vocabulary (CPV) codes, an EU-wide taxonomy of goods and services [48].