The name is absent

₁ 50

across economies is c =   ∑ c_k . Although economies have different length T^k, they are

50 k=1

given equal weight in our measure c of average cooperation across economies.

Figure 2: Average cooperation across treatments^(*)

monitoring punishment (non-
anonymous)

A Mann-Whitney test conducted on cooperation in non-anonymous public monitoring
shows significant difference with private monitoring (59.5%, p-value 0.0001) and with
anonymous public monitoring (58.6%, p-value 0.0000). Result 1 is consistent with data
reported in the literature of high levels of cooperation in the partner treatment. Similar to
a partner design, participants interact in pairs and know the whole individual history of
interaction, but unlike it, the match for the period is randomly picked from a group of
three other individuals.

We also report the distribution of the fifty economies by average cooperation level,
which is illustrated in Figure 3. About 38% of the economies have cooperation rates
above 98%. The superiority of non-anonymous public monitoring is clear also from the
average cooperation in the initial period across economies, shown in Table 4.

^(*) We aggregated economies from all cycles by treatment and carried out Mann-Whitney tests of pairwise
differences in cooperation between treatments. Differences are statistically significant at 1% level with two
exceptions: private monitoring vs. anonymous public monitoring and private monitoring with punishment
vs. non-anonymous public monitoring. One economy is one observation; in each comparison n1=n2=50.

18

<<   17   18   19   20   21   22   23   >>

More intriguing information