╨╧рб▒с>■ ,.■ + ье┴7 Ё┐bjbjUU .$7|7| l╩╩╩╩╓Е ╢ЎЎЎЎЎЎЎЎ( * * * * * * ;
[▐* ЎЎЎЎЎ* ЎЎ? ЎЎЎ( Ў( ( ( Ўъ╨~Rй┌╚о╩
( ( U 0Е ( 9
9
( ┘Estimating total number of dogs roaming in unsurveyed wards from the survey counts
The program opens to display a default name for the file containing the roaming dog counts and predictor variable values for each surveyed and unsurveyed ward. Edit to the name of your file and include the path if the file is not in the same folder as the regression estimator program.
The format of the required data file is:
First line: names of the predictor variables separated by commas (maximum of four predictor variables).
Subsequent lines: ward name or key number followed by the predictor variable values followed by the count of roaming dogs in the ward if it was surveyed. All values comma separated.
The predictor values can themselves be functions of other variables and they can also be coded values for qualitative variables, for example У1Ф if most people in the ward are Muslim and У-1Ф otherwise.
Click the Уread data from fileФ command button.
On the right the predictor variable names will be listed under the УconstantФ. To their left the text boxes contain zero default values for the coefficients used to give predicted dog counts based on the predictor variable values. The default constant is 10. To the left of those text boxes the check boxes select which of the predictor variables will be included in the regression estimator. Checking or unchecking those boxes causes the dog counts to be plotted against the corresponding predictor variable values. Up to 10 surveyed wards will be colour-coded, the rest will be shown using grey circles.
On the left you can select the model assumed for error about the predicted counts: lognormal with standard deviation proportional to predicted count; normal with constant variance about the predicted counts; negative binomial with variance proportional to the predicted count. The text box below the predictor variable coefficients shows the corresponding coefficient of variation, standard deviation or amount by which the variance to mean ratio exceeds 1.
Click the Уestimate population sizeФ command button. The maximum likelihood estimate for the total number of roaming dogs over all unsurveyed wards is shown in green, followed by the 95% confidence interval and the total count over the surveyed wards. If the estimate is shown in red it is unreliable Ц try the estimation again with different starting values for the selected predictor values entered in to the text boxes. The plot now shows the roaming dog counts in the surveyed wards plotted against the predicted values for those wards.
The lower plot shows how the maximised likelihood changes with the total number of roaming dogs Ц it should show a maximum at the maximum likelihood position on the horizontal axis. The dotted horizontal line is drawn at 1.92 below the maximum likelihood. If it fails to cut the maximised likelihood curve change the value in the text box to the right of the plot. Where it cuts the maximised likelihood curve provides confidence limits on the regression coefficients combined to provide the estimate of the roaming dog number. However that neglects variation about the model value. Adding that variation gives the 95% confidence interval shown on the plot as vertical green lines.
The confidence interval assumes that predictor variables were selected a priori. The width of the confidence interval will be underestimated if the final selection of predictor variables is made by picking the combination that seems to provide the best prediction.
A text box above the upper plot allows the name of any of the unsurveyed wards to be entered to give an estimate of the number of roaming dogs in that ward rather than the total over all unsurveyed wards. Estimates for all unsurveyed wards are also written to a Уward_predictions.txtФ file in the folder that contains the regression estimator program.
Simulating the estimation procedure
Clearing the text box that holds the name of the data file initiates simulation of data and subsequent estimation of the total number of roaming dogs simulated. Repeating the simulations allows the performance of the estimator to be evaluated. If the data file text box is cleared immediately the simulation proceeds using a total of 50 wards and the number of surveyed wards shown in the text box to the right of the Уsimulate data and estimateФ command button. If real data is read first and the text box then cleared the number of surveyed and unsurveyed wards used in the simulation is based on the number in the data file. In either case the simulation uses the predictor variable values entered in the text boxes and selected error model to first simulate roaming dog counts and then estimate the total number simulated. The number simulated is now shown as a vertical red line on the lower plot and summary results reported using the light green text above the upper plot. These compare the average number simulated over repeated simulations with the average number estimated and the number of simulations resulting in confidence intervals about the estimate that failed to include the simulated total.
The Уre-estimateФ check box that appears near the top of the screen can be checked to re-estimate from the previous simulation to see how bringing predictors in to the regression estimator that were not used in the simulation effects the estimate.
ЮиRS№№°№6Б]Б5Б\Б STstЭЮ╜╛ЙК║╗
ъы
╛┐╔╩,-.RS¤√√√√√√√√√√√√√√√√√√√√√√√√√∙√√¤¤¤,1Рh░В. ░╞A!░4"░4#Ра$Рk%░░┼░┼Р─
i8@ё 8NormalCJ_HaJmH sH tH 2@2 Heading 1$@&5Б\Б<A@Є б<Default Paragraph Font,B@Є, Body Text5Б\Б$ STstЭЮ╜╛ЙК║╗ъы
╛┐╔
╩
,-.RSШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0ААШ0АА0ААШ0А.Ш0ААШ0ААШ0АА hiby`C:\Documents and Settings\lex\Application Data\Microsoft\Word\AutoRecovery save of Document2.asdhibyЕC:\Program Files\straydog\regression estimator\Estimating total number of dogs roaming in unsurveyed wards from the survey counts.dochibyЕC:\Program Files\straydog\regression estimator\Estimating total number of dogs roaming in unsurveyed wards from the survey counts.dochibyQC:\Program Files\straydog\regression estimator\Using the regression estimator.dochibyQC:\Program Files\straydog\regression estimator\Using the regression estimator.dochibyQC:\Program Files\straydog\regression estimator\Using the regression estimator.doc @@@ Unknown GРЗz А Times New Roman5РАSymbol3&РЗz А Arial"ёИЁ╨hRМ║f[М║f\%!Ё4а┤┤ББr0dQ2ГЁ REstimating total number of dogs roaming in unsurveyed wards from the survey countshibyhiby■ рЕЯЄ∙OhлС+'│┘0╕РШЇ(< LX
tА
МШаи░фSEstimating total number of dogs roaming in unsurveyed wards from the survey countsstihibyatiibyibyNormal.dotthibyl.d4byMicrosoft Word 9.0m@
П@,I┘╚@вЁК┌╚\■ ╒═╒Ь.УЧ+,∙о0ThpФЬдм┤╝─╠
╘3фconservation research ltdn%Qа
SEstimating total number of dogs roaming in unsurveyed wards from the survey countsTitle
■ ■ !"■ $%&'()*■ ¤ -■ ■ ■ Root Entry └F0-]й┌╚/А1Table WordDocument .$SummaryInformation( DocumentSummaryInformation8 #CompObj jObjectPool 0-]й┌╚0-]й┌╚ ■ ■
└FMicrosoft Word Document
MSWordDocWord.Document.8Ї9▓q