Multiple Causes of Food Insecurity:
  Multiple Regression Analysis


          Reference: Gujarati (2004)
THE THREE-VARIABLE MODEL
THE THREE-VARIABLE MODEL
THE THREE-VARIABLE MODEL
Maternal education and community
  characteristics as indicators of
  nutritional status of children –
            application
    of multivariate regression



           Nutritional Status of Children   5
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).

                            Nutritional Status of Children               6
Empirical analysis




    Nutritional Status of Children   7
Empirical analysis




  Data description and methodology



     Nutritional Status of Children   8
Table 10.1 Means and standard deviations of
                      variables: Malawi sample
Variables                             Mean                  Standard deviation

BFEEDNEW                               1.57                       0.49

DIARRHEA                               0.16                       0.37

CALREQ                                 0.32                       0.47

ATTCLINI                               1.32                       0.59

AGEMNTH                               27.29                       16.28

CLINFEED                               2.29                       4.57

DRINKDST                               1.98                       1.39

EDUCSPOUS                              2.23                       1.30

LATERINE                               0.40                       0.49

PXFD                                   9.00                       9.85




                           Nutritional Status of Children                        9
Table 10.2 Determinants of weight for age Z-scores
Variables                           Model 1                                            Model 2

                     Coefficients              Std. error               Coefficients             Std. error

Constant                -3.03                    0.504                     -2.93                   0.492

EDUCSPOUS               0.173                    0.058                     0.156                   0.057

ATTCLINI                0.439                    0.144                     0.439                   0.142

DRINKDST               -0.143                    0.051                    -0.147                   0.05

LATERINE                0.134                    0.152                     0.152                   0.148

PXFD                    0.009                    0.008

AGEMNTH                -0.084                    0.021                    -0.088                   0.021

AGESQ                   0.001                    0.0003                    0.001                  0.0003

CLINFEED                0.717                    0.181                     0.699                   0.179

DIARRHEA               -0.608                    0.201                    -0.620                   0.198

BFEEDNEW                0.664                    0.226                     0.625                   0.224

CALREQ                                                                     0.566                   0.212

HEALTDST               -0.094                    0.071                     -0.06                   0.072


                                       Nutritional Status of Children                                         10
Table 10.3 Determinants of height for age Z-scores
Variables                           Model 1                                           Model 2

                     Coefficients               Std. error             Coefficients             Std. error

Constant               -2.159                     0.677                  -2.564                   0.685

EDUCSPOUS               0.048                     0.072                   0.106                   0.074

ATTCLINI                0.514                     0.18                    0.402                   0.177

DRINKDST               -0.024                     0.064                  -0.018                   0.062

LATERINE                0.072                     0.192                   0.114                   0.185

PXFD                    0.014                     0.01

AGEMNTH                -0.091                     0.034                  -0.094                   0.034

AGESQ                   0.001                    0.0004                  0.0009                  0.0004

CLINFEED                0.686                     0.227                   0.761                   0.224

DIARRHEA               -0.829                     0.261                  -0.932                   0.260

BFEEDNEW                0.149                     0.305                   0.174                   0.299

INSECURE                                                                  0.252                   0.085

HEALTDST               -0.106                     0.092                  -0.127                   0.091


                                      Nutritional Status of Children                                         11
Equations to predict the weight for age Z-scores
                  for model 1




                  Nutritional Status of Children   12
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




                       Nutritional Status of Children                                 13
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




                      Nutritional Status of Children                                 14
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




                               Nutritional Status of Children                         15
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




                                Nutritional Status of Children                          16
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
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.
                                             Nutritional Status of Children                                                  18
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


                                  Nutritional Status of Children                                             19
Figure 10.1 Histogram of standardized residuals of
                  weight for age




                  Nutritional Status of Children     20
Figure 10.2 Normal P-P plot of regression standardized
                      residuals




                    Nutritional Status of Children   21
Figure 10.3 Residuals plotted against predicted values
                  for weight for age




                    Nutritional Status of Children   22
Figure 10.4 Residuals plotted against predicted values
                  for height for age




                    Nutritional Status of Children   23

Topic 18 multiple regression

  • 1.
    Multiple Causes ofFood Insecurity: Multiple Regression Analysis Reference: Gujarati (2004)
  • 2.
  • 3.
  • 4.
  • 5.
    Maternal education andcommunity characteristics as indicators of nutritional status of children – application of multivariate regression Nutritional Status of Children 5
  • 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). Nutritional Status of Children 6
  • 7.
    Empirical analysis Nutritional Status of Children 7
  • 8.
    Empirical analysis Data description and methodology Nutritional Status of Children 8
  • 9.
    Table 10.1 Meansand standard deviations of variables: Malawi sample Variables Mean Standard deviation BFEEDNEW 1.57 0.49 DIARRHEA 0.16 0.37 CALREQ 0.32 0.47 ATTCLINI 1.32 0.59 AGEMNTH 27.29 16.28 CLINFEED 2.29 4.57 DRINKDST 1.98 1.39 EDUCSPOUS 2.23 1.30 LATERINE 0.40 0.49 PXFD 9.00 9.85 Nutritional Status of Children 9
  • 10.
    Table 10.2 Determinantsof weight for age Z-scores Variables Model 1 Model 2 Coefficients Std. error Coefficients Std. error Constant -3.03 0.504 -2.93 0.492 EDUCSPOUS 0.173 0.058 0.156 0.057 ATTCLINI 0.439 0.144 0.439 0.142 DRINKDST -0.143 0.051 -0.147 0.05 LATERINE 0.134 0.152 0.152 0.148 PXFD 0.009 0.008 AGEMNTH -0.084 0.021 -0.088 0.021 AGESQ 0.001 0.0003 0.001 0.0003 CLINFEED 0.717 0.181 0.699 0.179 DIARRHEA -0.608 0.201 -0.620 0.198 BFEEDNEW 0.664 0.226 0.625 0.224 CALREQ 0.566 0.212 HEALTDST -0.094 0.071 -0.06 0.072 Nutritional Status of Children 10
  • 11.
    Table 10.3 Determinantsof height for age Z-scores Variables Model 1 Model 2 Coefficients Std. error Coefficients Std. error Constant -2.159 0.677 -2.564 0.685 EDUCSPOUS 0.048 0.072 0.106 0.074 ATTCLINI 0.514 0.18 0.402 0.177 DRINKDST -0.024 0.064 -0.018 0.062 LATERINE 0.072 0.192 0.114 0.185 PXFD 0.014 0.01 AGEMNTH -0.091 0.034 -0.094 0.034 AGESQ 0.001 0.0004 0.0009 0.0004 CLINFEED 0.686 0.227 0.761 0.224 DIARRHEA -0.829 0.261 -0.932 0.260 BFEEDNEW 0.149 0.305 0.174 0.299 INSECURE 0.252 0.085 HEALTDST -0.106 0.092 -0.127 0.091 Nutritional Status of Children 11
  • 12.
    Equations to predictthe weight for age Z-scores for model 1 Nutritional Status of Children 12
  • 13.
    Table 10.4 Summaryof 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 Nutritional Status of Children 13
  • 14.
    Table 10.5 Summaryof 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 Nutritional Status of Children 14
  • 15.
    Table 10.6 Analysisof 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 Nutritional Status of Children 15
  • 16.
    Table 10.7 Analysisof 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 Nutritional Status of Children 16
  • 17.
    Table 10.8 Testsof 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 Testsof 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. Nutritional Status of Children 18
  • 19.
    Table 10.10 Partand 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 Nutritional Status of Children 19
  • 20.
    Figure 10.1 Histogramof standardized residuals of weight for age Nutritional Status of Children 20
  • 21.
    Figure 10.2 NormalP-P plot of regression standardized residuals Nutritional Status of Children 21
  • 22.
    Figure 10.3 Residualsplotted against predicted values for weight for age Nutritional Status of Children 22
  • 23.
    Figure 10.4 Residualsplotted against predicted values for height for age Nutritional Status of Children 23