5625.0 - Private New Capital Expenditure and Expected Expenditure, Australia, March 2013 Quality Declaration 
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 30/05/2013   
   Page tools: Print Print Page Print all pages in this productPrint All

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 $34,873m and the calculated standard error in this case is $716m. The standard error is then used to interpret the level estimate of $34,873m.

For instance, the standard error of $716m indicates that:

  • There are approximately two chances in three that the real value falls within the range $34,157m to $35,589m (34,873m $716m)
  • There are approximately 19 chances in 20 that the real value falls within the range $33,441m to $36,305m (34,873m $1,432m)

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 March Quarter 2013 estimates.

Buildings and Structures
Equipment, Plant and Machinery
Total
$m
$m
$m

Mining
625
52
625
Manufacturing
16
94
97
Electricity, Gas, Water and Waste Services
39
10
38
Construction
8
140
140
Wholesale Trade
14
74
78
Retail Trade
20
39
41
Transport, Postal and Warehousing
59
102
133
Information Media and Telecommunications
2
16
16
Financial and Insurance Services
9
50
51
Rental, Hiring and Real Estate Services
197
331
384
Professional, Scientific and Technical Services
38
47
61
Other Selected Services
70
126
154
Total
639
454
716
New South Wales
66
146
149
Victoria
66
126
151
Queensland
626
325
693
South Australia
170
45
186
Western Australia
72
157
181
Tasmania
59
14
61
Northern Territory
-
8
8
Australian Capital Territory
9
68
68
Australia
639
454
716

- 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 $43,801m and the next quarter the published level estimate is $34,873m.

In this example the calculated standard error for the movement estimate is $460m. The standard error is then used to interpret the published movement estimate of -$8,928m.

For instance, the standard error of $460m indicates that:
  • There are approximately two chances in three that the real movement over the two quarter period falls within the range -$9,388m to -$8,468m (-$8,928m $460m)
  • There are approximately nineteen chances in twenty that the real movement falls within the range -$9,848m to -$8,008m (-$8,928 $920m)

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

Buildings and Structures
Equipment, Plant and Machinery
Total
$m
$m
$m

Mining
158
57
173
Manufacturing
36
96
109
Electricity, Gas, Water and Waste Services
9
9
10
Construction
21
223
224
Wholesale Trade
45
89
105
Retail Trade
21
67
72
Transport, Postal and Warehousing
27
133
140
Information Media and Telecommunications
1
17
17
Financial and Insurance Services
27
50
60
Rental, Hiring and Real Estate Services
188
215
279
Professional, Scientific and Technical Services
51
85
96
Other Selected Services
54
127
137
Total
259
377
460
New South Wales
102
151
203
Victoria
45
159
169
Queensland
98
261
292
South Australia
157
45
157
Western Australia
151
182
239
Tasmania
72
32
88
Northern Territory
2
12
12
Australian Capital Territory
10
72
72
Australia
259
377
460