[MUSIC] Hi, in this module, I'm going to introduce you to some of the major sources of publicly accessible cross-sectional and longitudinal data. We're very fortunate to live in a time when there is a great deal of data out there that is readily accessible now to almost everybody with internet access. Just a few decades ago, it was only possible to analyze publicly available data by going to the computer center of a major research university, the data even though it was already public, often had to be ordered. First on punch cards, later as magnetic tapes, or in the 1990s on CD ROMs that were then loaded and put onto a mainframe. If you happened to live in a area that was hilly and had bad weather, you might have to walk uphill, through a snowstorm to go analyze your data and then perhaps walk up a hill again to go home when you're done. Again all that's changed and there's a lot of publicly accessible data, accessible to you via the Internet. One of the most important sources of publicly accessible available data is the Interuniversity Consortium for Political and Social Research. So this is an institution housed at the University of Michigan which for decades has served as a repository for research data sets collected by social scientist. Originally mainly in the United States but eventually from all over the world. So it goes back to the 1950s and originally again, it made data sets available to other researchers by punch card and other formats. It now holds 250,000 files divided into 21 special thematics collections. The files are searchable, the data sets all include documentation. So generally if you're about to set off on a new analysis one of the best places to start is by going to ICPSR taking the advantage of the search facility at their website to see if there are already some data sets related to your interests. The United Kingdom, the UK data archive, has a similar repository and indeed by now there are other repositories in different places around the world. Again, these repositories were probably the best place to start if you're looking for data on a topic that's interesting to you. In the United States there are also some very large public longitudinal surveys that are accessible in one form or another, and I want to talk about them. One of the most important and certainly one of the longest running is the Panel Study of Income Dynamics. This is a study that's been going on since the 1970s which started following some families at that time and now continues to follow them. It's already in the third generation. So it's an important source for studying income and employment dynamics over very long periods of time and the relationship to family dynamics in the United States. Another related very important set of data sets is the National Longitudinal Surveys. These are surveys that first in 1979 and then again at later points in time began following courts in a sample as they age through the workforce. So these are focus on employment following people as they make employment transitions, as they start job and end jobs. And then they also will get family dynamics and so forth. So like the PSID an important resource for understanding labor force participation dynamics over the life course. Now, since some of them have been going for several decades, they're actually turning into aging surveys as well. The Health and Retirement Survey, this is one of the biggest and most important surveys in the United States right now. This is a longitudinal study of the aging population of the United States that got started with samples that were initially collected in the early 1990s and had been followed ever since. Much of what we know about the dynamics of aging in the United States comes from the analysis of the Health and Retirement Survey. Thousands of papers has been published and again a lot of what we know about the trajectories that the elderly follows is they age the decent into dementia, the preservation of good health. And then the relationships of these trajectories to people's characteristics earlier in life. Their family situations, their financial situation. A lot of that comes from the health and retirement survey. So if you're going to be working on aging in the United States, it's almost certain that you're already working with the HRS. There's another very interesting and important survey that's been getting a lot of attention in recent decades which is the national longitudinal study of adolescent health. So this begun studying a cohort of adolescents sometime ago. And it's been following them ever since. So we get to follow people from the time that they were in high school as they go on to college or in some cases go straight to the workforce. By now some of the people in the survey are now in their 20s or some cases even older, they have started to marry. This is a remarkable survey because it collects incredible detail, not only on me, individuals that are sampled in the survey but also on their social context. Their peer networks within school, the characteristics of their schools and of course their family backgrounds. So a lot of what we know about the dynamics of adolescent behaviour in the United States now comes from the national longitudinal study of adolescent health. I want to mention how longitudinal household surveys from other part of the world as well, its not just the United States or this important long between the surveys of being carried out. One survey is going now for over decade actually since 1990's since Indonesian Family Life Survey which is been a national representative sample of Indonesia that's been followed for quite some time now that has studied the economic and family organization of households. So it's given us a great deal of insight into family dynamics and the health and the economic participation of people in Indonesia. It's also been used heavily in comparative studies between Indonesia and other countries for which there are also longitudinal studies. The Mexican Family Life Survey, as you can guess from the name is a longitudinal study families in Mexico. And then of course, accounts for the fact that there is a lot of migration to and from Mexico in the United States with special attention to the dynamics of that migration and then the relationship to household characteristics in Mexico. The German Socio-economic Panel is one of the major sources for the study of the economic dynamic of households and family dynamics in another developed country Germany. The UK Household Longitudinal Survey similarly follows household overtime in United Kingdom In recent years and has a very large sample. So again now increasingly these and other surveys are giving us a lot of detail at least in recent decades about the dynamics of households in terms of their economic behavior, their family organization, and in many cases there health dynamics as well. And many of the survey are accessible. Although they may have certain portions specially ones that related to do health or more sensitive information were you may have to go through application process to access. Now, I want to give special attention to aging surveys in various countries around the world. The health and retirement study that I mentioned earlier has inspired a variety of similar longitudinal studies of the aged in a variety of countries around the world. One reason that studies of the aged are so popular of course is that many countries, the population is getting older. And it's crucial to understand the dynamics of aging and understand how economic factors and other factors shape the trajectories that the elderly experience as they get older. So one of the really big aging surveys is the Survey of Health Ageing and Retirement in Europe. Again, inspired by the health and retirement survey and as well as other ageing surveys. ELSA the English Longitudinal Study of Aging. JSTAR, the Japanese Study of Aging and Retirement. MHAS, the Mexican Health and Aging Study. All these studies are actually quite similar. So similar that people are beginning to conduct comparative studies by pooling these data together. These studies typically include not only typical questionnaire surveys asking people about their health, their income, their relationships with their family members. Many of them also collect what we call biomarker data. Collecting blood, DNA other biomarkers that are direct measures of health conditions in the elderly that allow us to link very complex health conditions that are characteristic of the elderly to a wide variety of economic and family factors. So going forward we can look forward to a variety of comparative aging studies using the pooled data from these surveys.
