Estimation of coverage errors using Dual System of Estimation (DSE) Pres. 9

1. Estimation of coverage errors using Dual System of Estimation (DSE)Pres. 9

2. Tabulations & Dual System of Estimation (DSE) Tabulations: Initial tables (weighted) a. Estimated number of non-movers (P-sample) b. Estimated number of out-movers (P-sample) c. Estimated in-movers (P-sample) d. Estimated number of matched non-movers (P-sample) e. Estimated number of matched out-movers (P-sample)

3. Tabulations & Dual System of Estimation (DSE) Tabulations: Initial tables (weighted) f. Estimated number of erroneous inclusions in the census (E-sample) g. Estimated number of personscorrectly enumerated in the census but omitted in the PES (E-sample)

4. Basic Tabulations for Coverage Analysis Tabulations for coverage estimates (by age group & sex) E-sample estimates of population enumerated in the census P-sample estimates of total population DSE of True Population Net census coverage error and net coverage rate Census omissions & census omission rates Census erroneous inclusions & census erroneous inclusion rates Gross census coverage error & rate

5. Basic Tabulations for Coverage Analysis Matched population Matched non-movers + estimated matched out-movers (thus, in practice, the number of in-movers is assumed to be the same as that of out-movers) Matched Population = d + e Census population estimate Matched non-movers+ matched out-movers + population erroneously included in the census+ population correctly enumerated in the census but missed in the PESCensus Population Estimate = d+e+f+g Estimated PES population PES population = non-movers + in-movers = a+c

6. Dual System of Estimation (DSE) • Based on capture-recapture models • Chandrasekaran-Deming estimator (1949) assuming independence :

7. Dual System of Estimation (DSE) • First step to compute DSE is to determine correct enumerations in the census. ”Correct” has 4 dimensions: • Appropriateness: the person should be included in the census • Uniqueness: the person is only once in the census • Completeness: the person has sufficient information recorded to be identified • Geographic correctness: the person is enumerated at his/her right location

8. ) Dual System of Estimation (DSE) (contd.) The form of DSE used in PES is as follows: Where C = census count II = number of persons with insufficient information CE = estimated number of correct enumeration from the E-sample Ne = estimated number of people from the E-sample Np = estimated number of people from the P-sample M = estimated number of persons from the P-sample population who matched to the census

9. Dual System of Estimation (DSE) (contd.) • M=estimated number of persons from the P-sample population who matched to the census =Matched non-movers + matched out-movers Matched out-movers=Out-movers matched rate*Number of in-movers Example: Matched non-mover=1000 Matched out-mover=150 Out-movers=200 In-movers=300 Matched out-movers=(150/200)*300=225 Total matched person=1000+225=1225 (Procedure C)

10. Dual System of Estimation (DSE) (contd.) Estimate of True population True population = (Number of persons with sufficient information x Correct enumeration rate from E-sample) x (1/ Match rate for P sample persons)

11. ) Dual System of Estimation (DSE) (contd.) Example of Estimate of True Population C (census count) = 1000 II (number of persons with insufficient information) = 50 CE (estimated number of correct enumeration from the E-sample) = 940 Ne (estimated number of people from the E-sample) = 950 Np (estimated number of people from the P-sample) = 960 M (estimated number of persons from the P-sample population who matched to the census = 900 = (1000 – 50) * (940/950) * (960/900) = 1002.7, i.e. 1003 persons

12. ) Dual System of Estimation (DSE) (contd.) Example of Estimate of True Population C (census count) = 1000 II (number of persons with insufficient information) = 50 CE (estimated number of correct enumeration from the E-sample) = 940 Ne (estimated number of people from the E-sample) = 950 Np (estimated number of people from the P-sample) = 960 M (estimated number of persons from the P-sample population who matched to the census = 900 Erroneous inclusions = Ne – CE = 950-940 = 10 = (960/900) * [(1000-50) – 10] = 1002.7, i.e. 1003 persons

13. Dual System of Estimation (DSE) (contd.) Net Coverage Error The difference between what should have been counted, thus True Population and what was counted in the census Net coverage error = True Population - Census Count Net Coverage Error Rate Net coverage error relative to the true population (an important indicator of the quality of census coverage)

14. Dual System of Estimation (DSE) (contd.) Omissions Net coverage error = True Population – Census Count Net coverage error = Omissions – Erroneous Enumeration Omissions = True Population-Census Count+ Erroneous OmissionRate= (Omissions/TruePopulation)*100

15. Coverage rate, Adjustment factor and Erroneous inclusion rate Coverage rate (match rate) = Matched_Population/PES_Population*100 Erroneous Inclusion Rate = Erroneous_Inclusions/ Census_Count Adjustment (Correction) factor = True Population/Census_Count

16. Dual System of Estimation (DSE) (contd.) Gross coverage error The sum of Omissions and Erroneous Inclusions Gross coverage error rate per unit enumeration This is the absolute gross error relative to census enumerated population But...to use with caution

17. Thank You!