Introduction
Defining and measuring socio-economic position
The asset-based approach to measuring socio-economic position
Weighting the items in a wealth index
Which concept of long-term SEP does a wealth index represent?
Aim
Methods
Details of dichotomisation of categorical variables
Floor material
-
Lower SEP group: sand, smoothed mud
-
Higher SEP group: smooth cement, tile, other
Cooking fuel
-
Lower SEP group: firewood, crop residue, other
-
Higher SEP group: paraffin, electricity, charcoal
Water supply
-
Lower SEP group: personal open unprotected well, communal open unprotected well, river, spring, lake, reservoir, other
-
Higher SEP group: piped into dwelling, piped outside dwelling, communal standpipe, personal handpump, communal handpump, protected spring
Toilet facility
-
Lower SEP group: no toilet facility, other
-
Higher SEP group: flush toilet, VIP latrine, traditional latrine with roof, latrine without roof
Results
Distribution of Indices
Weights assigned to index components
Item | Item weight | ||
---|---|---|---|
PCA
|
MCA
| ||
Toilet facility:
| |||
Flush toilet |
0.2760
|
2.081
| |
VIP latrine |
0.0894
|
0.515
| |
Traditional latrine with roof |
0.0015
|
-0.019
| |
Latrine no roof |
-0.0613
|
-0.125
| |
None or other |
-0.0923
|
-0.197
| |
Water source:
| |||
Piped inside dwelling |
0.2762
|
2.428
| |
Piped outside dwelling |
0.1631
|
0.857
| |
Communal standpipe |
0.1251
|
0.161
| |
Personal handpump or well |
0.0154
|
0.011
| |
Communal handpump or well |
-0.2270
|
-0.138
| |
River, lake, spring, reservoir, or other |
-0.0433
|
-0.179
| |
Cooking fuel:
| |||
Collected firewood |
-0.3049
|
-0.153
| |
Purchased firewood |
0.1252
|
0.176
| |
Paraffin, gas or charcoal |
0.2196
|
0.721
| |
Electricity |
0.2451
|
2.537
| |
Crop residue, saw dust, or other |
0.0043
|
-0.084
| |
Floor material:
| |||
Sand |
-0.0078
|
-0.168
| |
Smoothed mud or other |
-0.3113
|
-0.154
| |
Smooth cement, wood, or tiles |
0.3310
|
0.613
| |
Electricity:
| Yes |
0.3427
|
1.6
|
No |
-
|
-0.1
| |
Radio:
| Yes |
0.0193
|
0.007
|
No |
-
|
-0.009
| |
TV:
| Yes |
0.2836
|
1.726
|
No |
-
|
-0.070
| |
Bike:
| Yes |
0.0025
|
0.002
|
No |
-
|
-0.001
| |
Car:
| Yes |
0.1885
|
2.247
|
No |
-
|
-0.028
| |
Motorbike:
| Yes |
0.0432
|
0.869
|
No |
-
|
-0.003
| |
Domestic servant:
| Yes |
0.1426
|
1.32
|
No |
-
|
-0.025
| |
Agricultural land:
| Yes |
-0.2280
|
-0.081
|
No |
-
|
0.589
|
Item | Item weight | ||
---|---|---|---|
PCA
|
Equal weights
|
Inverse proportion
| |
Toilet facility:
| |||
some toilet facility |
0.1429
|
1
|
1.2
|
Water source:
| |||
protected source |
0.1703
|
1
|
1.5
|
Cooking fuel:
| |||
more likely to have been purchased |
0.4320
|
1
|
11.8
|
Floor material:
| |||
modern |
0.4084
|
1
|
5.0
|
Electricity:
|
0.4600
|
1
|
17.1
|
Radio:
|
0.0225
|
1
|
1.8
|
TV:
|
0.4012
|
1
|
25.7
|
Bike:
|
0.0014
|
1
|
2.8
|
Car:
|
0.2766
|
1
|
82.3
|
Motorbike:
|
0.0725
|
1
|
275.1
|
Domestic servant:
|
0.2190
|
1
|
53.4
|
Agricultural land:
|
-0.3072
|
1
|
1.1
|
Agreement of the indices with consumption
% Households moving between quintiles of the wealth index and quintiles of per capita consumption expenditure | 1. PCA index | 2. PCA index using binary variables | 3. Equal weights index | 4. Inverse proportion index | 5. MCA index |
---|---|---|---|---|---|
Same quintile | 28.9 | 28.0 | 26.6 | 28.2 | 29.2 |
Move one quintile | 34.8 | 36.0 | 37.8 | 33.6 | 34.3 |
Move two quintiles | 21.5 | 20.6 | 22.3 | 22.5 | 22.1 |
Move three quintiles | 11.6 | 12.2 | 10.5 | 11.3 | 11.4 |
Move four quintiles | 2.9 | 3.1 | 2.8 | 4.4 | 3.0 |
Kappa
|
0.11*
|
0.10*
|
0.082*
|
0.10*
|
0.12*
|
Comparing the indices
1. PCA | 2. PCA (binary) | 3. Equal weights | 4. Inverse proportion | 5. MCA | |
---|---|---|---|---|---|
1. PCA
| - | ||||
2. PCA (binary)
| 41.9% κ = 0.27* | - | |||
3. Equal weights
| 35.9% κ = 0.20* | 73.6% κ = 0.67* | - | ||
4. Inverse proportion
| 39.3% κ = 0.24* | 69.5% κ = 0.62* | 67.7% κ = 0.60* | - | |
5. MCA
| 75.6% κ = 0.69* | 51.5% κ = 039* | 40.6% κ = 0.26* | 43.4% κ = 0.29* | - |
Wealth indices being compared | % Households moving between quintiles | ||||
---|---|---|---|---|---|
Same quintile
|
Move 1 quintile
|
Move 2 quintiles
|
Move 3 quintiles
|
Move 4 quintiles
| |
Index 1 (PCA all categories) and Index 2 (PCA binary variables) | 41.9 | 41.3 | 13.3 | 4.5 | 0.4 |
Index 1 (PCA all categories) and Index 3 (Equal weights) | 35.9 | 38.5 | 18.8 | 7.1 | 1.1 |
Index 1 (PCA all categories) and Index 4 (Inverse proportion) | 39.3 | 39.2 | 13.3 | 8.6 | 0.98 |
Index 1 (PCA all categories) and Index 5 (MCA) | 75.6 | 18.9 | 5.8 | 0.65 | 0.33 |
Index 2 (PCA binary variables) and Index 3 (Equal weights) | 73.6 | 18.7 | 4.5 | 4.0 | 0.5 |
Index 2 (PCA binary variables) and Index 4 (Inverse Proportion) | 69.5 | 23.1 | 5.6 | 2.7 | 0.33 |
Index 2 (PCA binary variables) and Index 5 (MCA) | 51.5 | 36.3 | 11.6 | 1.5 | 0.36 |
Index 3 (Equal weights) and Index 4 (Inverse proportion) | 67.7 | 28.8 | 3.5 | 0.91 | 0.37 |
Index 3 (Equal weights) and Index 5 (MCA) | 40.6 | 38.4 | 16.4 | 4.9 | 1.0 |
Index 4 (Inverse proportion) and Index 5 (MCA) | 43.4 | 39.8 | 10.5 | 6.7 | 0.90 |
% Households moving between quintiles of wealth index and per capita consumption expenditure | ||||||
---|---|---|---|---|---|---|
Consumption equivalence scale
|
Same quintile
|
Move 1 quintiles
|
Move 2 quintiles
|
Move 3 quintiles
|
Move 4 quintiles
|
Kappa (SE)
|
Total consumption expenditure | 28.8 | 34.7 | 21.7 | 12.1 | 2.7 | 0.10 (0.005) |
Per adult consumption expenditure | 27.3 | 35.7 | 21.1 | 12.8 | 3.0 | 0.090 (0.005) |
Per capita consumption expenditure | 28.9 | 34.8 | 21.5 | 11.6 | 2.9 | 0.11 (0.005) |