1Additional program details are provided in periodic reports issued by the U.S. Congressional Research Service, notably Lake (2003), Whittaker and Isaacs (2012), and Isaacs (2013).
2The IUR is the three-month average ratio of persons receiving UI benefits to the number of persons covered by the UI system. The TUR is a three-month average of the unemployment rate published by the U.S. Bureau of Labor Statistics (BLS).
3The weekly “trigger” notices for the EB program back to 2002 and the complete EUC program are available online at http://www.ows.doleta.gov/unemploy/trigger/ and http://www.oui.doleta.gov/unemploy/euc_trigger/. Similar trigger date information for the TEUC program is no longer available online but was kindly provided to me by Scott Gibbons of the U.S. Department of Labor.
4Figure 1 does not reflect several temporary suspensions of the EUC program arising from legislative disagreements that occurred in April, June-July, and December of 2010. During those periods, reauthorization was expected and individuals were allowed to receive benefits through their current EUC tier and retroactive benefits for the next tier after reauthorization. It is therefore likely that the suspension periods did not significantly offset any behavioral responses to the overall extension programs. The suspension periods are largely addressed in the empirical analysis through the use of complete monthly date dummies in my econometric equations.
5In 2011–13, eight states passed legislation that reduced their normal UI duration below 26 weeks. As an extreme example, in July 2013 North Carolina implemented new legislation that reduced normal UI duration to 19 weeks based on a formula tied to the prevailing state unemployment rate. This and related changes in their state UI laws caused the state to lose eligibility for the federal extensions, reducing total available UI weeks to 19, as reflected in the minimum weeks plot near the end of the sample frame in Panel A of Figure 1. Reductions in normal UI weeks translate into reduction in available weeks through the EUC and EB programs (see Isaacs 2012). I account for these changes in my database of available UI weeks.
6In addition, selected recent work has focused on direct measures of search activity using high-frequency survey or online data from periods corresponding to the recent benefit extensions (Krueger and Mueller 2011, Marinescu 2013). The results from these papers regarding UI extension effects on search intensity and job finding are mixed.
7The choice of the 2011 end date is described in Section 2.1.
8Rare exceptions to this exact timing can occur, such as during temporary shutdowns of the U.S. federal government (the most recent were during 1995 and late 2013, which are outside my sample frame).
9The survivor curves are calculated based on the complete set of available observations, which is larger for the uncorrected transitions due to fewer restrictions placed on the underlying matched sample.
10The share of unemployment spells lasting at least six months in the CPS cross-section data is around 30 percent during 2007–11. The discrepancy between the implied durations for my sampled spells and the CPS cross-section is largely due to the impact of flow-based versus stock-based sampling. Simulations provided in Farber and Valletta (2013) show that the empirical flow-based and stock-based duration distributions largely converge in steady state.
11Attrition arises in these data because the CPS survey does not track households or individuals who move from their surveyed address. The comparison of the first and second rows in Table 1 (“Currently unemployed” and “Valid matches”) illustrates the combined impact of attrition, nonresponse, and the matching validation screen based on demographic characteristics. The implied monthly non-match rate is about 9 percent: matching is feasible for 75 percent (three-fourths) of the sample based on the four-month rotation group structure, but the observation counts in the second row are only about 66 percent of those in the first row on average. Past research reports little or no impact of attrition on longitudinal estimates from matched CPS files (see Neumark and Kawaguchi 2004 for discussion). Moreover, Rothstein (2011, page 162) reports no conditional correlation between the 2008–11 UI extensions and CPS matched sample attrition.
12The U.S. unemployment rate averaged 7.6 percent during 2007–11, with a peak of 10.0 percent in October 2009. By contrast, it averaged 5.2 percent during 2000–04, with a peak of 6.3 percent in June 2003.
13Among the sample of ineligibles in both periods, about 60 percent are re-entrants, 15–20 percent are new entrants, and 20–25 percent are job leavers (quits).
14Industry of prior employment is not defined for new labor force entrants; the industry tabulations in the Additional file 1 are restricted to job leavers and re-entrants.
15As noted earlier, the date dummies largely account for the potential effects of temporary suspensions of extended benefit (EUC) availability in 2010.
16See the Additional file 1: Table A2 for the complete list and corresponding regression results (except the industry categories).
17This variation raises the possibility of a regression discontinuity (RD) design for the empirical analysis, in which the pattern of unemployment transitions is compared across individuals in states that are on either side of an unemployment threshold that triggers additional UI extension weeks. Marinescu (2013) implemented an RD strategy using data from online job searches. With my matched CPS data, this strategy would produce observation counts that are too small to yield adequate statistical precision.
18Complete coefficient estimates for the column (4) and (8) specifications for eligibles (Table 3) and ineligibles (Table 4) are listed in the Additional file 1: Table A2 (excluding the coefficients on the industry, state, and time dummies).
19Job losers unemployed for less than six months are not eligible for extended benefits and hence are not directly affected by the expansions. However, their search intensity may be affected by the expectation of eventual eligibility for extended benefits, implying that they are probably not an appropriate placebo or control group for assessing the effects of extended benefits. The uniformly negative coefficients for this group in Panel B of Table 3 are consistent with this interpretation, although the effects are not precisely estimated.
20Industry of prior employment is not defined for new labor force entrants and therefore is excluded from the regressions for the ineligible sample. Results for the eligible sample are nearly identical to those listed in Table 3 when industry controls are excluded from those regressions.
21Additional file 1: Table A4 lists parallel results based on the uncorrected transitions. This table shows a mixture of positive and negative coefficients, many of them statistically significant, with different signs across the two sample periods. This pattern likely reflects the unreliability of uncorrected transitions for the ineligible group, which is dominated by labor force entrants, and it precludes reliable inferences.
22Similar multinomial logit regressions for the sample of ineligibles produced PBD coefficients that were highly insignificant in all cases.
23The calculation yielding a 7.8 percent unemployment rate is the ratio of the PBD and PBD*state unemp. rate coefficients from Panel A: 0.0262/.00334=7.84.
24The calculation combining the two coefficients is as follows: −0.0262+11*(.00334)=0.0105.
25I truncate durations at 24 months because very few spells are observed beyond that point in my data; accounting for the small number of longer spells does not have a meaningful impact on expected duration.
26Rothstein (2011) and Farber and Valletta (2013) translate their estimates into an impact on the overall unemployment rate. For the recent extension period (2008 forward), they find only a modest impact on the unemployment rate, on the order of 0.5 percentage points or less. Based on rough calculations, my estimated PBD responses imply a similar modest effect on the unemployment rate.