American trade policy towards Sub Saharan Africa –- a meta analysis of AGOA

(1)

T-stat

(2)

T-stat

(3)

T-stat

(4)

T-stat

(5)

T-stat

(6)

T-stat

(7)

T-stat

Constant

2.693^***

1.932^***

-0.253*

-0.572^***

-0.406^***

-28.82^***

-0.360^***

(0.077)

(0.079)

(0.101)

(0.097)

(0.109)

(0.001)

(0.006)

no. of explanatory variables

0.0422^***

0.0416^***

0.0416^***

0.0416^***

0.0425^***

(0.000)

(0.000)

(0.000)

(0.000)

(0.000)

N (in logs)

0.0175^***

0.000443

0.00515

-0.00195

-0.0162^***

(0.000)

(0.006)

(0.005)

(0.006)

(0.000)

No. of years used (log)

0.0448^***

-0.392^*

0.0198

-0.269

-0.378^***

(0.002)

(0.166)

(0.086)

(0.375)

(0.025)

No. of countries (log)

0.384^***

-0.0535^***

-0.0642^***

-0.0561^***

-0.0285^***

(0.003)

(0.010)

(0.010)

(0.010)

(0.000)

annual = 1

1.241^***

-2.880^*

1.092^***

(0.190)

(1.214)

(0.031)

selection correction = 1

-0.190^***

-0.189^***

-0.252^***

(0.049)

(0.049)

(0.004)

published = 1

0.0106

2.287^*

0.0117^***

(0.009)

(0.977)

(0.000)

country effects = 1

-0.283^*

0.384

-0.235^***

(0.115)

(0.560)

(0.016)

time effects = 1

0.00382

0.0105

-0.00122

(0.046)

(0.048)

(0.004)

cross section = 1

-2.256^***

-4.005

-2.485^***

(0.320)

(4.257)

(0.044)

other preferences included = 1

0.200^***

0.699

0.151^***

(0.061)

(3.553)

(0.010)

gravity regression = 1

-0.466^***

4.300^**

-0.379^***

(0.066)

(1.514)

(0.011)

agoa dummy = 1

-2.707^***

-2.196^***

-2.673^***

(0.262)

(0.422)

(0.103)

robust s.e. = 1

-0.144^***

-0.139^***

0.00619^***

(0.016)

(0.017)

(0.001)

product effects = 1

0.153^**

-0.864

0.391^***

(0.047)

(0.570)

(0.005)

single country analysis = 1

0.834^***

0.972^***

(0.125)

(0.015)

logged dep. var. = 1

0.288^***

-0.116

0.331^***

(0.041)

(0.208)

(0.005)

product group = ”All/Total”

-0.00637

-0.0311

(0.056)

(0.068)

product group = ”Apparel & Textiles”

-0.0369

-0.0436

(0.045)

(0.045)

product group = ”Agriculture”

0.0609^*

0.0550^*

(0.026)

(0.026)

regions included = AGOA countries

-0.0514

-2.874

(0.068)

(3.493)

regions included = AGOA + N. Africa

-0.287^***

-6.300^**

(0.069)

(2.054)

definition of dep. var. = Exports

-0.214

0.696

(0.264)

(3.502)

definition of dep. var. = Imports

0.156

1.813

(0.245)

(3.455)

time frequency = Annual

0.488^**

(0.157)

time frequency = Monthly

-0.0248

-2.959^*

(0.134)

(1.208)

econometric method = GMM

-0.00367

-0.657

(0.057)

(0.607)

econometric method = Heckman/Tobit

-0.873^***

-2.552

(0.121)

(1.567)

level of aggregation = Aggregate

0.0686⁺

0.0712⁺

(0.039)

(0.040)

level of aggregation = Less Aggregate

0.0779^*

-2.206^*

(0.040)

(0.976)

Precision

0.00449^***

-2.228^***

2.584^***

-0.258⁺

4.384^***

0.0128^***

2.489^***

(0.000)

(0.009)

(0.342)

(0.149)

(1.056)

(0.000)

(0.107)

Observations

173

173

173

173

173

173

173

goodness of fit-χ²

120496.0

7710.6

862.6

1074.5

836.8

1.31107e+10

316374.3

model χ²

1217.4

114002.8

120850.8

120639.0

120876.6

600194512.9

1.37106e+10

Standard errors in parentheses. All explanatory variables divided by standard error.

The last two columns use the square of the standard error as weights