NlsyLinks (version 2.0.6)

SurveyDate: Dataset containing survey details for each subject, for each year

Description

Each row represents a survey that a subject completed (or didn't complete). It can be very helpful when restructuring the NLS investigator extracts into a longitudinal dataset that's aligned by age (instead of by survey wave). The Age variables can help to align other response variables across subjects. While the `SurveySource` indicates where to look for their responses.

These variables are useful to many types of analyses (not just behavior genetics), and are provided to save users time.

Format

A data frame with 580,752 observations on the following 6 variables.

SubjectTag

see the variable of the same name in Links79Pair

SurveySource

The location of that subject's survey responses that year. Values are NoInterview, Gen1, Gen2C or Gen2YA.

SurveyYear

The year/wave of the survey.

SurveyDate

The exact date of the administered survey.

AgeSelfReportYears

The subject's age, according to a their own response, or their mother's response.

AgeCalculateYears

The subject's age, calculated from subtracting their birthday from the interview date.

Age

The subject's age, which uses AgeCalculateYears or AgeSelfReportYears if it's not available.

Source

Gen1 information comes from the Summer 2013 release of the NLSY79 sample. Gen2 information comes from the January 2015 release of the NLSY79 Children and Young Adults sample. Data were extracted with the NLS Investigator (https://www.nlsinfo.org/investigator/).

Details

The AgeSelfReportYears and AgeCalculateYears variables usually agree, but not always. The Age variable uses AgeCalculateYears (or AgeSelfReportYears when AgeCalculateYears is missing).

The exact date of birth isn't public (only the subject's month of birth). To balance the downward bias of two weeks, theri birthday is set to the 15th day of the month to produce AgeCalculateYears.

In the Gen2 Child dataset, self-reported age is stated by month (eg, the child is 38 months old); a constant of 0.5 months has been added to balance the downward bias. In the Gen2 YA and Gen1 datasets, self-reported age is stated by year (eg, the subject is 52 years old); a constant of 0.5 years has been added.

Examples

library(NlsyLinks) #Load the package into the current R session.

summary(SurveyDate)
table(SurveyDate$SurveyYear, SurveyDate$SurveySource)
table(is.na(SurveyDate$AgeSelfReportYears), is.na(SurveyDate$AgeCalculateYears))

if( require(ggplot2) & require(plyr) ) {
  dsSourceYear <- plyr::count(SurveyDate, c("SurveyYear", "SurveySource"))
  dsSourceYear <- dsSourceYear[dsSourceYear$SurveySource != "NoInterview", ]
  
  ggplot(dsSourceYear, aes(x=SurveyYear, y=freq, color=SurveySource)) +
    geom_line(size=2) +
    geom_point(size=5, shape=21) +
    scale_color_brewer(palette = "Dark2") +
    theme_bw() +
    theme(legend.position=c(0,0), legend.justification=c(0,0))
    
  ggplot(SurveyDate, aes(x=AgeSelfReportYears, y=AgeCalculateYears)) +
    geom_abline() +
    geom_point(shape=21) +
    theme_bw() 
}