All of the regressions are dummy parameters to have census year, battle, many years, state from delivery, and you can cohort out of beginning, and you may region of birth manner. Research is aggregated to say regarding beginning ? seasons of beginning ? census seasons telephone setting in the first line, however, on private height toward IV regressions. Comprehend the notes to help you Desk 1 .
Discussion
The fresh IV estimates signify the fresh causal effects of early teenager relationship and you can dropout status with the future poverty is substantial. The newest standard rates mean that marrying younger advances the potential a great young bride will end up inside impoverishment later on in daily life by to 30 percentage factors. Shedding from high school provides a fairly quicker, yet still generous, 11 percentage area influence on coming impoverishment. These types of email address details are sturdy to the point off aggregation, LIML estimation, alterations for migration, and you can a processing form strategy. The person-peak OLS estimates to possess very early teen wedding are small, if you are aggregated OLS rates give a quotation which is of your exact same magnitude since IV prices.
To raised appreciate this the fresh new IV and aggregated OLS prices differ really regarding individual-level OLS prices, We now talk about the latest role of aspect mistake. Inside census studies, years at first matrimony was determined from the said big date out-of earliest relationship and you may day from delivery (week and you can 12 months). Usually just one individual fulfills regarding census form for the whole home. This might be going to exacerbate dimensions error while the person doing the census may not have right information about other home members’ schedules regarding beginning and you will first relationship. When you look at the 1970 and you may 1980, the brand new census function teaches individuals to “bring your very best estimate” when sometimes of those times are “unfamiliar.” 19
Given that tiny fraction out of very early adolescent marriage ceremonies is really small, one mismeasurement away from date regarding birth otherwise big date from matrimony-the two variables always construct age to start with wedding-does trigger an extremely higher down bias when you look at the brand new OLS imagine of your very early teen ount from measurement mistake, the fresh new wrongly categorized teen brides is also outnumber the genuine adolescent brides, resulting in good-sized attenuation bias.
To better understand the incidence out-of dimension error when you look at the reported times, take into account the 1975 Federal Virility Survey (NFS). It was the latest 5th inside the several surveys presented most of the five years to examine ily planning. Brand new interesting function of your own survey in 1975 is the fact that boffins made a decision to reinterview a specified test of women in the 1970 survey. New reinterview decide to try comes with dos,355 light women in their basic marriages have been continuously hitched, whoever decades at relationships are lower than twenty five years, and you can whose husbands had already been married only when. The 1975 and you will 1970 surveys inquire date out of birth and you can day away from first relationship, having each other groups of solutions being submitted on the 1975 try. So because of it subset of females, I will assess a lower life expectancy bound to your misreports by the contrasting this new exact same female’s solutions more a beneficial five-year go out vista.
Misreporting fundamentally declines since the a good woman’s said ount out-of mistake in such almost every other teams was smaller in comparison
Table 8 tabulates how often brand new responses in the 1975 survey do not satisfy the responses on 1970 questionnaire. For your try, times away from beginning do not concur 4% of the time, and you may times regarding relationships do not agree twelve% of the time. As a result, you to a beneficial woman’s age at relationship measured during the decades doesn’t fall into line for eleven% of observations on the sample. Mismatch pricing also are said in Dining table 8 having groupings founded on the good woman’s stated marriage age in the 1970 questionnaire. For these marrying from the or underneath the chronilogical age of 15 inside brand new 1970 survey, 8% from birth times and you will 35% out of relationship times do not align around the questionnaire decades. For it category, 39% of your required relationship age disagree along the surveys. The 
amount of dimension error on the census has a tendency to become also larger because 1975 NFS tested just ladies who had never ever divorced along with lady respond to questions on themselves.