Woodrow-Lafield, Karen A., Xiaohe Xu, Thomas Kersen, and Bunnak Poch. 2001. Naturalization Experiences of U.S. Immigrants. Pp. 106-11, 2000 Proceedings of the Social/Government Statistics Section, 2000 Joint Statistical Meetings. Alexandria, Virginia: American Statistical Association.
K. A. Woodrow-Lafield, Sociology, Anthropology, and Social Work, MSU, Mississippi State, MS 39762
Key Words: Naturalization, Immigrants, Linkage
(Corrected version)
The publication included this text on page 108 that has been removed:
The magnitude of the problem is small. In the immigrant data, 8,926,246 records, persons of all ages, were “original” records, and 299,032 records were “duplicate” records. The overcount rate of actual immigrants in publicly released data is thus about 3.4 percent. Of these latter, the number of duplicated identification numbers was only 159,420 as some identifi¬cation numbers were found more than once among the 299,032 “duplicate” records. In the naturalization data, 5,538,975 (all ages) records were “original” records, and 124,901 records were “duplicate” records. Error in publicly released naturalization data is thus an overcount rate of naturalizations by about 2.3 percent. Of these latter, the number of duplicated identification numbers was only 62,987 as the remainder were third or higher-order incidences.
This revised manuscript includes the substituted text below that more accurately describes this topic:
The magnitude of the problem is small. In the immigrant data, 8,926,246 records, persons of all ages, were “original” records, and 159,420 records were “duplicate” records. The overcount rate of actual immigrants in publicly released data is about 1.8 percent. The number of duplicated identification numbers was only 139,612 as some numbers were found more than once in a pool of 299,032 records containing duplicated numbers. In the naturalization data, 5,538,975 (all ages) records were “original” records, and 62,987 records were “duplicate” records. Error in publicly released naturalization data is thus an overcount rate of naturalizations by about 1.2 percent. The number of duplicated identification numbers was only 61,914 in a pool of 124,901 records with duplicated numbers, as the remaining records were third or higher-order incidences. To summarize in a different way, about 1.8 percent of immigrant counts and 1.2 percent of naturalization counts, as released, should not be counted.
INTRODUCTION
The Immigration-to-Naturalization Project (INP) is a comprehensive study of the timing of naturalization for several million immigrants admitted by the U.S. Immigration and Naturalization Service (INS) over fiscal years 1978-1991. This group of entrants represents about one-third of immigrants admitted over the past fifty years. The 1990 census was the first since the 1920 census to show more aliens (about two-thirds) than naturalized citizens, and this differential persisted in the 1990s (Gibson and Lennon 1999). This shift was largely due to demographic dynamics, new immigration, and the dynamics of making the transition to naturalized citizenship. Nevertheless, questions about recent cohorts’ propensity to naturalize have arisen and added to scrutiny of immigrants’ assimilation within American society, e.g., Pan (1999a). The INP is timely because immigrants are applying for naturalization in unprecedented numbers, and naturalization approvals attained new peaks in the late 1990s. This paper describes the INP and ongoing analyses, noting security constraints underlying the project given confidential data requirements. The INP can become an excellent resource for modeling naturalization in America for immigrant cohorts over two significant decades.
IMMIGRANTS AND NATURALIZATIONS
Official statistics about immigrants and immigration have often been neglected at the same time that their numbers and significance were rising. A literature of critique emerged in the 1980s and a National Academy of Sciences (NAS) panel challenged federal agencies toward improvement (Levine, Hill, and Warren 1985). The original NAS study was revisited in late 1992, with support from the National Institute of Child Health and Human Development (NICHD) and the U.S. Immigration and Naturalization Service (Edmonston 1996). The U.S. General Accounting Office (1998a) followed with a report on whether key recommendations from the 1985 and 1996 reports had been fulfilled. Two other reports (U.S. General Accounting Office 1998b, 1998c) assessed federal statistics on immigration for policymaking and the foreign-born population. To summarize, valuable advances were made, and official statistics became timelier and more complete.
Although the original NAS study noted inaccuracies in naturalizations statistics due to unevenness of data quality, the report expressed optimism about improvements as a consequence of developments in automated data processing (ADP) (Levine, Hill, and Warren 1985, p. 49). To quote, “the new ADP systems being implemented . . . will make it straightforward to link records of immigration or adjustment of status with subsequent naturalizations . . .” (p. 137). The later NAS study gave little attention to official INS statistics and INS microdata (Edmonston 1996).
An extensive set of public use immigrants microdata files (1972-1997) is available from the Inter-University Consortium for Political and Social Research (ICPSR) at the University of Michigan. The INS Statistics Office developed complete documentation for the 1972-1988 files, and released these and the 1989-1997 files for sale through the U.S. Department of Commerce, National Technical Information Service (NTIS), from which ICPSR acquired them to make available to member institutions.
Federal and state government agencies are major users of public use immigrants microdata files. INS has provided these data to the U.S. Census Bureau for age, sex, and country-of-origin tabulations for estimating components of change (authorized and unauthorized immigration) in the postcensal population estimates program and for the decennial census coverage evaluation programs (Fay, Passel, and Robinson 1988; Robinson et al. 1993; Himes and Clogg, 1992; Warren and Passel 1987; Passel and Woodrow 1987; Woodrow and Passel 1990; Woodrow 1992; Bean et al. 1998; Woodrow-Lafield 1998a; Johnson 1996).
INS distributes public use naturalizations microdata files for 1972-1996 (not available through NTIS or ICPSR). For a long time, these were considered as containing publicly recorded data, i.e., filed in the courts, and names and alien numbers were included. With greater public concern about microdata having identifying information, INS ceased release of complete records. As might be expected given the data source as administrative records gathered during emergence of automated data processing systems and computing technology, both immigrants and naturalizations data have known limitations.
The U.S. Immigration and Naturalization Service (INS) provides naturalization benefits on the basis of requirements, whether under general or special provisions, concerning age, lawful admission, and residence in the United States, plus demonstrating ability to speak, read, and write the English language, knowledge of the U.S. government and U.S. history, and having good moral character. INS immigrant records include such fixed or ascribed characteristics as sex, age, country of birth, and such “acquired” characteristics as class of admission, prior experience as nonimmigrant, and month and year of admission that are nevertheless fixed henceforth. INS naturalization records include such fixed characteristics as sex, age, and country of birth and “acquired” characteristics such as marital status, occupation, month and year of naturalization, provisions under which naturalized, and month and year of admission as resident. From the 1998 edition of the Statistical Yearbook of the Immigration and Naturalization Service (U.S. Immigration and Naturalization Service 2000), differences in occurrence of naturalization over 1961-1998 are discernible, as composition of immigrants changed. Representation of Europeans decreased among persons naturalized and the shares of North Americans and Asians increased. Many of the naturalizations occur within six to eight years of residence. The median residence years at naturalization are usually lower for Asians and higher for North Americans. An innovative analysis by Liang (1994) showed that for Mexicans, probabilities of naturalizing were lower than for other groups for the first decade, rising over the 12th to 17th years after immigrating.
There are some examples of longitudinally linked administrative records utilized on a restricted basis for naturalization study. The first, the INS 1971 Immigrant Cohort Sample, is a unique one-percent microdata sample (3,758 cases) from the cohort of persons admitted to permanent resident alien status during July 1970-June 1971 with naturalization experiences through February 1981. Thirty percent had naturalized in the first decade, comparable with 30, 25, and 32 percent naturalizing by late 1979 for those immigrating in 1967, 1968, and 1969, respectively (Jasso and Rosenzweig 1990:107-110; U.S. Select Commission on Immigration and Refugee Policy 1981). Jasso and Rosenzweig (1990) analyzed Eastern vs. Western Hemisphere origins and country-of-origin characteristics, finding higher naturalization for Eastern Hemisphere immigrants and for women from countries in which English is the official language.
In the late 1980s, the INS, responding to NAS recommendations, began to support linking immigrant and naturalization records for studying patterns in the timing of naturalization. The methodology used to link immigrants with naturalizations was simpler in utilizing microdata and more expansive in not being restricted to a sample. Nevertheless, the NAS panel’s optimism about ADP improvements for facilitating this record linkage was not borne out. This record linkage has not been done regularly despite its value for policy relevant research noted for a single entry cohort (Jasso and Rosenzweig 1990; Edmonston 1996:51-2).
The resulting linked records files, the INS 1977 Immigrant-Naturalization Cohort and INS 1982 Immigrant-Naturalization Cohort, have been utilized only partially (Jasso and Rosenzweig 1995; Rytina 1998). Several editions (1993-1997) of the Statistical Yearbook reported completed naturalization rates for these cohorts by country of birth. The 1996 and 1997 editions of the Statistical Yearbooks added tabulations by class of admission and occupation. These were not updated in the 1998 edition, and this may have been deferred due to lesser naturalizations in 1998. Differences in timing of naturalization point to the value of a database with which to examine intercohort and intracohort variation by origin, demographic characteristics, and admission criteria.
Few social science researchers have worked with multiple INS files, preferring to work with one or two years (beginning and ending years) for longitudinal comparisons. Leading in the direction of using multiple years (1972- 1991) are Greenwood and McDowell (1999), noting the data’s considerable volume. Also meeting this challenge are studies of immigrants settling in the New York City metropolitan area (Salvo and Ortiz 1992), Asian immigrants (Lobo and Salvo 1998a), and Irish immigrants (Lobo and Salvo 1998b).
To use multiple years of immigrants and naturalizations micro data files, extensive preparations were involved. With changes in the Immigration Nationality Act, there were changes in admission categories. Even origin country codes and names shifted in time as national identities changed. The INP involved rigorous efforts to set time-consistent coding and to create a database resilient to specific time period of reference. The work of Greenwood and Ziel (1997) was helpful, as were various editions of the Statistical Yearbook. INP researchers implemented these tasks first with public-use immigrant records.
PROGRESS TOWARD THE DATABASE
To create the INP data archive, confidential identifiers on immigrants and naturalizations records were necessary. INS provided access to the immigrants and naturalizations data including identifiers to Dr. Woodrow-Lafield as an INS Expert (without compensation). Two other members of the research team hold security clearances for confidential data access. This solution was a major accomplishment given the significant confidentiality constraints on INS data. INS collects information deemed necessary for receipt of the benefit of either immigration or naturalization, and INS does not collect items considered highly sensitive (race or income). Nor did the format of the provided data include the most sensitive information that could be used for fraudulent purposes (names and actual alien numbers), but encrypted alien numbers were provided.
The Secure Data Laboratory was established in the Social Science Research Center (SSRC) as a “statistical data enclave” very similar to similar facilities (e.g., Census Research Data Centers and the NCHS Research Data Center) with access strictly limited to INP researchers. Guidelines for Research Site Security Issues and Maintaining Confidentiality describe the security procedures. Since mid-May 1999, the study has been in Phase III or the Main Secure Operations Phase after receipt of confidential micro data and Phase IV or Main Analysis/Modeling Operations Phase. The INP is currently maintained on two Pentium III 450 MHz desktop computers having high storage capacity (36 gigabytes). This equipment has been adequate for initial stages of the INP, but updated computer technology will be essential for full analytic capability or utilizing the dataset extensively.
Linking strategies might have been as simple as sorting datasets on encrypted alien number. The INP team had access to less extensive linking data than INS statisticians had been able to utilize—the alien-number (or A-number) or INS identification number, full name of the immigrant (or naturalizing individual), and the sequential ordering of the A-numbers. Nevertheless, INS statisticians had found name was far less useful than alien number as a basis for the initial linkage.
The INP first created the 1982 Immigration-to-Naturalization Cohort, and verified successful replication of the INS 1982 Immigrant-Naturalization Cohort. Then the project team turned toward creating all cohorts. An unanticipated problem arose when some encrypted alien identification numbers were found duplicated not only within individual years but also across subsequent years. Users familiar with documentation for the 1977 and 1982 Immigrant-Naturalization Cohorts may have noted mention of 2,960 duplicates within the 1977 file and 12 duplicates within the 1982 file. The extent to which duplicate immigrant records were found across years was not previously reported. Upon scrutiny, some appear to be associated with duplicated data entry for a single individual, but others appear due to assignment of the same identifier to more than one individual or due to error in the identifier. Based on discussions with INS, the best solution seemed to be to accept the first record as “original” and to designate as “duplicate” the second or higher order records having the same encrypted alien number. We continue to investigate this problem.
The magnitude of the problem is small. In the immigrant data, 8,926,246 records, persons of all ages, were “original” records, and 159,420 records were “duplicate” records. The overcount rate of actual immigrants in publicly released data is about 1.8 percent. The number of duplicated identification numbers was only 139,612 as some numbers were found more than once in a pool of 299,032 records containing duplicated numbers. In the naturalization data, 5,538,975 (all ages) records were “original” records, and 62,987 records were “duplicate” records. Error in publicly released naturalization data is thus an overcount rate of naturalizations by about 1.2 percent. The number of duplicated identification numbers was only 61,914 in a pool of 124,901 records with duplicated numbers, as the remaining records were third or higher-order incidences. To summarize in a different way, about 1.8 percent of immigrant counts and 1.2 percent of naturalization counts, as released, should not be counted.
We conducted analyses of the likelihood of duplication of an identification number. For immigrant records, the presence of a duplicated record was greater for those admitted during fiscal year 1979 and those from primarily refugee-sending countries of Southeast Asia (Vietnam, Laos, and Cambodia), as well as Cuba, Mexico, and the Soviet Union. For naturalization records, individuals naturalizing in fiscal year 1982 were more likely to have a duplicate record, and so were immigrants from the Philippines, Korea, Mexico, Cuba, Vietnam, China, and India. These results suggest our procedures are appropriate in correcting for processing problems for refugees arriving circa 1980, and that potential selection biases of excluding duplicates are minimal.
The provisional database was developed for all immigrant entry cohorts 1978-1992, with naturalizations through the 1996 fiscal year. The number of immigrant records over 1978-1991 matched with a naturalization record as of 1996 was 2,805,599 and 6,120,647 immigrant records remained without a corresponding naturalization record.
Our initial analyses focus on entry cohorts 1978-1987 for the ten leading sending countries (China, India, Korea, the Philippines, Vietnam, Jamaica, Mexico, Cuba, the Dominican Republic, and Colombia), accounting for 4,682,025 immigrant records. These cohorts were admitted before INS processed permanent residence applications (2.68 million) for aliens legalized under the Immigration Reform and Control Act of 1986 (IRCA). We excluded more recent cohorts to maintain minimum exposure time for naturalization. Because children of naturalizing adults may derive citizenship from parents and this cannot be identified within the database, we included only persons aged 21 years and older at immigration. For adults at immigration in these cohorts and from the selected countries, the number of linked immigration-to-naturalization records is 1,938,744.
One dependent variable, for which we report descriptive results here, is simply having naturalized during the observation interval, that is, as of 1996. Another dependent variable for many of the INP analyses will be waiting time until or duration to naturalization, including right-censored observations, calculated on the basis of month and year of naturalization and month and year of admission as lawful permanent resident from the immigrant record. This variable has two versions: years and “century months” of residence.
Most of the independent variables were easily categorized except for a complicated one—visa class of admission. Visa classes of admission include numerically limited and numerically unlimited immigrants. Broadly speaking, visas are distributed among categories of family sponsorship (FP), employment sponsorship (EP), and humanitarian criteria. We further incorporate distinctions according to principals or derivative beneficiaries and specific preference categories (prior to those under the Immigration Act of 1990), establishing fourteen categories. Again, children are not included in these analyses. Among family preferences, first, second, fourth and fifth preferences are shown as translating to seven dummy variables. Third and sixth preferences are translated to four categories. There are two immediate relatives categories: spouses as principals and parents as principals. The last category is encompasses refugees, asylees, and others without distinction as to principals or derivative beneficiaries.
SOME RESULTS FROM INP DATA
Overall, 42 percent had naturalized as of the end of fiscal year 1996, about the same as for immigrants 18 and older in the 1990 census (Chiswick and Sullivan 1995), subject to data quality (Passel and Clark 1997; Passel, Clark and Fix 1997; Fix and Passel 1994; Woodrow 1992). From these INP data, the highest percentages are for certain Asian countries—Vietnam (65 percent), the Philippines (62 percent) and China (51 percent). However, comparably high percentages are found for Colombia (46 percent), Cuba (40 percent), and Jamaica (37 percent) relative to other Asian countries--India (44 percent) and Korea (38 percent). The lowest percentages are for Mexico (18 percent) and the Dominican Republic (24 percent). The percentage naturalized is greater for those having more time to naturalize, e.g., earlier entry cohorts.
The median values on duration to naturalization vary from about 9 years for immigrants (including refugees) from Vietnam to about 13 years for those from Mexico and 12 years for those from the Dominican Republic.
Those admitted under professional categories show higher percentages naturalized, but other employment-sponsored immigrants also show high naturalization relative to family-sponsored immigrants. Women have somewhat higher naturalization levels, as are also found for younger and unmarried immigrants. Those immigrants with nonimmigrant experience, i.e., adjustments, are clearly more likely to have naturalized by 1996. Focusing on characteristics, origin differentials are evident with higher percentages naturalized for Asian origin groups and lower naturalization for Latin American origins with the exception of Cuba and Colombia. Although patterns on age group, marital status, nonimmigrant experience appear similar for specific countries, the same is not true when looking at percentages naturalized by gender. Men from China, India, and Vietnam show higher percentages naturalized than women, but women from these Latin American countries show higher percentages naturalized than men.
CONCLUSIONS AND FURTHER RESEARCH
Sociological studies have explored immigrant groups’ patterns of naturalizing as a consequence of degrees of human capital and social capital as well as origin differentials by distance, English-speaking, and political structures. From the INP, study of naturalization can advance in ways similar to advances in educational attainment, marital formation, marital dissolution, labor force participation, and fertility that became possible with the advent of longitudinal surveys and sophisticated statistical methodologies with which to disentangle duration or aging, cohort, and period influences for various behavioral outcomes In reviewing such accomplishments, Crimmins (1993) asserted scientists are now ready to “address questions of change in demographic behavior across and within individuals” and “examine how demographic processes are affected by change in the context of the time and the place in which individuals live.” The advent of methods for dealing with change over time (event history analysis, survival analysis) leads to studying the process of demographic change rather than merely changes in demographic status. For the study of naturalization, we can study the process of naturalizing rather than merely changes in citizenship status.
The INP offers the promise of being a key data source with which to reach greater understanding of the macro-linkages and micro-linkages leading immigrants to become permanent settlers in the United States. The challenge is a complicated one in every dimension. This happens to be the best of times and the worst of times for this research. On one hand, the time is ideal because major legislation led to increased and more diverse immigration over the past two decades. These immigrants’ assimilation will be key for Americans’ future as their contributions, especially their children, may be beneficial (Smith and Edmonston 1997). Another view, however, is that the time is poor because so many among recent immigrants would have unique naturalization experiences after living here as an unauthorized resident or a close relative to such a person (Woodrow-Lafield 1998b). An unanticipated consequence of IRCA and other INS programs was emergence of huge backlogs in naturalization applications in the mid-1990s. Further analytic research is oriented toward illuminating the highly heterogeneous patterns of immigrants’ transitions into American citizenship. We are conducting several analyses to investigate timing of naturalization with hazards models with covariates gleaned from these administrative records. The volume of immigration, the heterogeneity of immigration, the time series, and the complexity of kinds of admission under the Immigration and Nationality Act mean tasks and studies in the INP are many and challenging. INP studies are just beginning to disentangle influences of such factors as gender, origin, and admission criteria for the timing of naturalization. The goal is to continue the Immigration-to-Naturalization Project because the data provide a substantial longitudinal framework for augmentation into the future.
* This research was supported by a grant to the first author from the National Institute of Child Health and Human Development (NICHD) (R01 HD37279). We greatly appreciate cooperation of the U.S. Immigration and Naturalization Service and the assistance of Robert Bach, Lisa Roney, Michael Hoefer, John Bjerke, Nancy Rytina, Linda Gordon, and Bernadette Lyles.
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