Page 38 - 2010 (3) Agricultural Census 2010, Punjab Report

Volume 3: Special Reportscomprise two reports i.e. one for Gilgit Baltistan and
other for Azad Jammu & Kashmir. Each report contains tabulations at the district
and overall levels in acres for the local users.

QUALITY OF CENSUS DATA.

A sample-based census gives rise to sampling error as well as the non-sampling
error.ln spite of the best efforts made by the ACO during sample selection
procedures, data collection and data processing methods, some margin of non-
sampling errors is inevitable. Therefore, the most important consideration was to
control the extent of non-sampling errors during the census. In addition, the quality of
the census data was considered on the criterion of:

i) Internal consistencies and

ii) Comparison with other corresponding series

The quality of data had been assured by the following methods:

SAMPLING ERROR:

To estimate sampling error the relative variance (R.V and then the coefficient of
)
variation (C.V.)were calculated for a number of important data items and presented
in Appendix-lll. The formula used for estimating relative varianceand the coefficient
of vaiiationat district, province and country levels is described in the succeeding
paragraphs

At the district level, R. V. was estimated simply by first raising the sample
observations of each Patwar Circle to stratum level using the overall raising factor for
each holding but excluding all National Certainty Holdings (NCHs), and then
summing up to obtain an estimate for each half stratum as describedbelow:
r, I o, 1lvu-Ni-t'ti'1 ,, Qt Ni ,, I
i, \- \- ')'h'tjkl* r-)\1'/h'tjkr I
-\-l
'n'r-LlL L p 'L/-t p I
i I k l' r h'tir k I' 'n'ti -)

,, f qi (N* _Ni_N i\ y0,,,,-
Orr:411 s *gf zr*r]
/J Prrio 77 Prr, )

Then, the R V for the district estimate of aggregates of the attribute is obtained by
taking the square of differences between estimates for successive pairs of half strata
divided by the district estimates as follows:
r ^ ^ .t2

y
\ / L \ lJ
TL
l
vo,(f\=l cv (t\1' =fl"'="' I
si mi rar'v' the R' * bute is
rii'ffi l= ;i ;:[jTri
-\
lL \ /t
Tl X
I