5. Maternal education and community
characteristics as indicators of
nutritional status of children –
application
of multivariate regression
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6. Main results
• Step 1: Estimating the coefficients of the model(Table 10.2,10.3).
• Step 2: Examining how good the model predicts(Table 10.4,10.5).
• Step 3: Hypotheses testing.
• Tests about the equation(Table 10.6,10.7).
• Tests about individual coefficients(Table 10.8,10.9).
• Part and partial correlation coefficients.
• Step 4: Checking for violations of regression assumptions.
• Checking normality of the errors(Table 10.10,Figure 10.1,10.2).
• Checking for homogeneity of variance of the residuals(Figure
10.3,10.4).
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12. Equations to predict the weight for age Z-scores
for model 1
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13. Table 10.4 Summary of the model for determinants of
weight for age Z-scores
Adjusted R2 Std. error of
Models R R2
the estimate
1 0.488 0.238 0.203 1.09
2 0.506 0.256 0.222 1.079
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14. Table 10.5 Summary of the model for determinants of
height for age Z-scores
Adjusted R2 Std. error of
Models R R2
the estimate
0.418 0.174 0.13 1.285
1
2 0.448 0.201 0.157 1.265
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15. Table 10.6 Analysis of variance table for weight for
age Z-scores
Sum of
Models df Mean Square F Sig
Squares
I Regression 89.139 11 8.104 6.797 0
Residual 284.936 239 1.192
Total 374.075 250
II Regression 95.757 11 8.705 7.475 0
Residual 278.318 239 1.165
Total 374.075 250
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16. Table 10.7 Analysis of variance table for height for age
Z-scores
Sum of
Models df Mean Square F Sig
Squares
I Regression 70.948 11 6.45 3.901 0.00
Residual 335.649 203 1.653
Total 406.597 214
II Regression 81.525 11 7.411 4.628 0.00
Residual 325.072 203 1.601
Total 406.597 214
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17. Table 10.8 Tests of individual coefficients for determinants of
weight for age Z-scores
Variables Model 1 Model 2
t-stat P value t-stat P value
Constant -6.016 0.000 -5.956 0.000
EDUCSPOUS 2.987* 0.003 2.70* 0.007
ATTCLINI 3.047* 0.003 3.102* 0.002
DRINKDST -2.817* 0.005 -2.938* 0.004
LATERINE 0.882 0.378 1.03 0.304
PXFD 1.185 0.237
AGEMNTH -4.041* 0.000 -4.282* 0.00
AGESQ 3.096* 0.002 3.386* 0.001
CLINFEED 3.966* 0.000 3.911* 0.00
DIARRHEA -3.018* 0.003 -3.126* 0.002
BFEEDNEW 2.935* 0.004 2.791* 0.006
CALREQ 2.668* 0.008
HEALTDST -1.32 0.188 -0.851 0.396
Note: * denotes at 1 per centof Children
Nutritional Status level of significance. 17
18. Table 10.9 Tests of individual coefficients for determinants of
height for age Z-scores
Variables Model 1 Model 2
t-stat P value t-stat P value
Constant -3.187 0.002 -3.745 0.000
EDUCSPOUS 0.661 0.509 1.437 0.152
ATTCLINI 2.863* 0.005 2.273** 0.024
DRINKDST -0.37 0.712 -0.286 0.775
LATERINE 0.375 0.708 0.615 0.539
PXFD 1.479 0.141
AGEMNTH -2.642* 0.009 -2.78* 0.006
AGESQ 1.949** 0.053 2.022** 0.044
CLINFEED 3.018* 0.003 3.394* 0.001
DIARRHEA -3.171* 0.002 -3.584* 0.00
BFEEDNEW 0.489 0.625 0.580 0.563
INSECURE
2.977* 0.003
HEALTDST -1.15 0.252 -1.395 0.164
Note: * denotes at 1 per cent level of significance, ** denotes at 5 per cent level of significance.
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19. Table 10.10 Part and partial correlation coefficients for weight
for age and height for age
Variables Weight for age Height for age
Part correlation Partial correlation Part correlation Partial correlation
EDUCSPOUS 0.169 0.19 0.042 0.046
ATTCLINI 0.172 0.193 0.183 0.197
DRINKDST -0.159 -0.179 -0.024 -0.026
LATERINE 0.05 0.057 0.024 0.026
PXFD 0.067 0.076 0.094 0.103
AGEMNTH -0.228 -0.253 -0.168 -0.182
AGESQ 0.175 0.196 0.124 0.136
CLINFEED 0.224 0.248 0.192 0.207
DIARRHEA -0.17 -0.192 -0.202 -0.217
BFEEDNEW 0.166 0.187 0.031 0.034
HEALTDST -0.075 -0.085 -0.073 -0.08
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20. Figure 10.1 Histogram of standardized residuals of
weight for age
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21. Figure 10.2 Normal P-P plot of regression standardized
residuals
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22. Figure 10.3 Residuals plotted against predicted values
for weight for age
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23. Figure 10.4 Residuals plotted against predicted values
for height for age
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