5625.0 - Private New Capital Expenditure and Expected Expenditure, Australia, June 2012 Quality Declaration 
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 30/08/2012   
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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 $43,821m and the calculated standard error in this case is $542m. The standard error is then used to interpret the level estimate of $43,821m.

For instance, the standard error of $542m indicates that:

  • There are approximately two chances in three that the real value falls within the range $43,279m to $44,363m (43,821m ± $542m)
  • There are approximately 19 chances in 20 that the real value falls within the range $42,737m to $44,905m (43,821m ± $1084m)

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 June Quarter 2012 estimates.

Buildings and Structures
Equipment, Plant and Machinery
Total
$m
$m
$m
Mining
135
115
178
Manufacturing
33
71
79
Electricity, Gas, Water and Waste Services
178
10
176
Construction
12
187
188
Wholesale Trade
13
49
52
Retail Trade
52
37
71
Transport, Postal and Warehousing
96
113
142
Information Media and Telecommunications
8
32
33
Financial and Insurance Services
33
33
50
Rental, Hiring and Real Estate Services
245
113
261
Professional, Scientific and Technical Services
113
103
163
Other Selected Services
64
167
192
Total
351
355
542
New South Wales
68
210
222
Victoria
117
126
182
Queensland
216
186
290
South Australia
51
86
115
Western Australia
255
167
333
Tasmania
2
45
45
Northern Territory
29
17
35
Australian Capital Territory
2
21
21
Australia
351
355
542



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 $35,709m and the next quarter the published level estimate is $43,821m.

In this example the calculated standard error for the movement estimate is $490m. The standard error is then used to interpret the published movement estimate of $8,112m.

For instance, the standard error of $490m indicates that:
  • There are approximately two chances in three that the real movement over the two quarter period falls within the range $7,622m to $8,602m ($8,112m ± $490m)
  • There are approximately nineteen chances in twenty that the real movement falls within the range $7,132m to $9,092m ($8,112m ± $980m)

The following table shows the standard errors for June Quarter 2012 movement estimates.

Buildings and Structures
Equipment, Plant and Machinery
Total
$m
$m
$m
Mining
108
83
130
Manufacturing
35
98
87
Electricity, Gas, Water and Waste Services
102
12
102
Construction
15
179
179
Wholesale Trade
53
63
82
Retail Trade
51
57
78
Transport, Postal and Warehousing
73
101
130
Information Media and Telecommunications
8
31
28
Financial and Insurance Services
32
33
48
Rental, Hiring and Real Estate Services
130
155
194
Professional, Scientific and Technical Services
37
111
119
Other Selected Services
88
157
186
Total
266
385
490
New South Wales
98
189
207
Victoria
127
141
191
Queensland
76
175
183
South Australia
49
99
123
Western Australia
185
174
257
Tasmania
12
47
47
Northern Territory
30
14
32
Australian Capital Territory
3
22
22
Australia
266
385
490