5625.0 - Private New Capital Expenditure and Expected Expenditure, Australia, Jun 2010
Previous ISSUE Released at 11:30 AM (CANBERRA TIME) 26/08/2010
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APPENDIX SAMPLING ERRORS

LEVEL ESTIMATES

INTRODUCTION

The estimates in this publication are based on a sample drawn from units in the surveyed population. Because the entire population is not surveyed, the published estimates are subject to sampling error. The most common way of quantifying such sampling error is to calculate the standard error for the published estimate or statistic.

EXAMPLE OF USE

The following example illustrates how to use the standard error to interpret a level estimate.

Let us say that the published level estimate for total capital expenditure is \$27,735m and the calculated standard error in this case is \$654m. The standard error is then used to interpret the level estimate of \$27,735m.

For instance, the standard error of \$654m indicates that:

• There are approximately two chances in three that the correct value falls within the range \$27,081m to \$28,389m (\$27,735m ± \$654m)
• There are approximately 19 chances in 20 that the correct value falls within the ranges \$26,427m to \$29,043m (\$27,735m ± \$1,308m)

The correct value in this case is the result we would obtain if we could enumerate the total population.

The following table shows the standard errors for June Quarter 2010 estimates.

 Buildings and Structures Equipment, Plant and Machinery Total \$m \$m \$m Mining 84 127 147 Manufacturing 13 171 173 Electricity, Gas, Water and Waste Services 111 25 111 Construction 11 254 254 Wholesale Trade 13 61 64 Retail Trade 18 79 79 Transport, Postal and Warehousing 48 96 110 Information Media and Telecommunications - 34 34 Financial and Insurance Services 2 21 21 Rental, Hiring and Real Estate Services 292 403 522 Professional, Scientific and Technical Services 92 89 128 Other Selected Services 109 100 152 Total 369 529 654 New South Wales 164 278 354 Victoria 174 387 405 Queensland 190 247 344 South Australia 113 88 135 Western Australia 75 163 172 Tasmania 4 18 20 Northern Territory 6 41 42 Australian Capital Territory 1 7 7 Australia 369 529 654 - nil or rounded to zero (including null cells)

MOVEMENT ESTIMATES

EXAMPLE OF USE

The following example illustrates how to use the standard error to interpret a movement estimate.

Let us say that one quarter the published level estimate for total capital expenditure is \$23,837m and the next quarter the published level estimate is \$27,735m. In this example the calculated standard error for the movement estimate is \$652m. The standard error is then used to interpret the published movement estimate of \$3,898m.

For instance, the standard error of \$652m indicates that:
• There are approximately two chances in three that the correct movement over the two quarter period falls within the range \$3,246m to \$4,550m (\$3,898m ±\$652m)
• There are approximately nineteen chances in twenty that the correct movement falls within the range \$2,594m to \$5,202m (\$3,898m ± \$1,304m).

The following table shows the standard errors for June Quarter 2010 estimates.

 Buildings and Structures Equipment, Plant and Machinery Total \$m \$m \$m Mining 48 134 142 Manufacturing 29 164 167 Electricity, Gas, Water and Waste Services 33 24 41 Construction 10 274 274 Wholesale Trade 13 127 129 Retail Trade 30 107 118 Transport, Postal and Warehousing 30 135 145 Information Media and Telecommunications 7 21 22 Financial and Insurance Services 13 79 80 Rental, Hiring and Real Estate Services 336 265 425 Professional, Scientific and Technical Services 35 100 105 Other Selected Services 55 115 126 Total 353 513 652 New South Wales 95 310 330 Victoria 310 245 408 Queensland 73 305 312 South Australia 12 103 107 Western Australia 73 178 192 Tasmania 6 20 21 Northern Territory 8 48 51 Australian Capital Territory 5 7 9 Australia 353 513 652