5625.0 - Private New Capital Expenditure and Expected Expenditure, Australia, Sep 2013
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 28/11/2013
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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 \$40,742m and the calculated standard error in this case is \$411m. The standard error is then used to interpret the level estimate of \$40,742m.

For instance, the standard error of \$411m indicates that:

• There are approximately two chances in three that the real value falls within the range \$40,331m to \$41,153m (40,742m ± \$411m)
• There are approximately 19 chances in 20 that the real value falls within the range \$39,920m to \$41,564m (40,742m ± \$822m)

The real 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 September Quarter 2013 estimates.

 Buildings and Structures Equipment, Plant and Machinery Total \$m \$m \$m Mining 99 32 108 Manufacturing 28 79 96 Electricity, Gas, Water and Waste Services 41 20 51 Construction 9 161 160 Wholesale Trade 18 73 78 Retail Trade 53 77 97 Transport, Postal and Warehousing 78 132 154 Information Media and Telecommunications 1 21 21 Financial and Insurance Services 7 36 36 Rental, Hiring and Real Estate Services 199 100 213 Professional, Scientific and Technical Services 36 88 93 Other Selected Services 98 117 152 Total 249 315 411 New South Wales 83 157 195 Victoria 158 130 222 Queensland 127 192 226 South Australia 100 64 129 Western Australia 80 138 152 Tasmania 43 20 48 Northern Territory 1 6 6 Australian Capital Territory - 16 16 Australia 249 315 411 - 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 \$41,668m and the next quarter the published level estimate is \$40,742m.

In this example the calculated standard error for the movement estimate is \$514m. The standard error is then used to interpret the published movement estimate of -\$926m.

For instance, the standard error of \$514m indicates that:
• There are approximately two chances in three that the real movement over the two quarter period falls within the range -\$1,440m to -\$412m (-\$926m ± \$514m).
• There are approximately 19 chances in 20 that the real movement falls within the range -\$1,954m to \$102m (-\$926m ± \$1,028m)

The following table shows the standard errors for September Quarter 2013 movement estimates.

 Buildings and Structures Equipment, Plant and Machinery Total \$m \$m \$m Mining 102 112 161 Manufacturing 35 83 95 Electricity, Gas, Water and Waste Services 30 28 40 Construction 9 188 189 Wholesale Trade 27 66 76 Retail Trade 55 98 108 Transport, Postal and Warehousing 31 174 172 Information Media and Telecommunications 3 23 24 Financial and Insurance Services 28 25 34 Rental, Hiring and Real Estate Services 258 137 303 Professional, Scientific and Technical Services 47 72 87 Other Selected Services 95 124 179 Total 319 390 514 New South Wales 76 206 234 Victoria 176 147 242 Queensland 186 222 283 South Australia 91 65 107 Western Australia 63 168 174 Tasmania 47 37 61 Northern Territory 1 10 10 Australian Capital Territory 1 16 16 Australia 319 390 514