time series analysis interpolation

[Jim Tarvid <tarvid ls net>]

Struggling with the application of function interpolation Help gratefully accepted. File can be downloaded from http://docs.google.com/a/ls.net/leaf?id=0B7iRSxKe1Dz-ODY3ODc5YTktMzg5OS00YTEzLTkxMTctNTAzMTMwYTEyNTFj&hl=en

 I have a lot more of these to do.

Goal. Compute asfr(time, age-group) where time is [1991,. 2021] and age-group=[15-19,20-24,25-29,30-34,35-39,40-44,45-49]

Given.

1. start and stop months of survey
2. age-group of respondent at time of survey
3. fertility rate based on number of births in the three year period befor interview

Imputations.

1. Start and stop dates are the 15th of the month of the dates of field work.
2. Interview conducted at the midpoint of the start and stop dates
3. Fertility observation ascribed to 18 months before the midpoint

Data observations.

1. Survey name
2. vlookup of date from the survey-date worksheet (abscissae)
3. births per thousand by survey and age-group (ordinates)

Output.asfr by calendar year and age-group

Formula.

=interpolation('asfr-dhs'!$B$2:$B$6,'asfr-dhs'!$C$2:$C$6,'asfr-ts'!$A3,0)

where
'asfr-dhs'!$B$2:$B$6 are the imputed dates of the observations
'asfr-dhs'!$C$2:$C$6 are the observations
'asfr-ts'!$A3 is the target date
0 is the method

Result. #NAME?






--
Rev. Jim Tarvid, PCA
Galax, Virginia
http://ls.net
http://drupal.ls.net

Attachment: asfr.gnumeric
Description: application/gnumeric