Table 1 Descriptive statistics of the main variables
From: The effect of Internet use on adolescent nutritional outcomes: evidence from China
Variables | Definitions | All | Internet users | Non-users | Difference |
|---|---|---|---|---|---|
(1) | (2) | (3) | (4) | ||
Internet | 1 if use Internet, 0 otherwise | 0.610 | 1.000 | 0.000 | 1.000 |
(0.488) | (0.000) | (0.000) | (0.000) | ||
Internet time | How many leisure hours per day are spent on the Internet | 1.326 | 2.147 | 0.000 | 2.147*** |
(2.269) | (2.563) | (0.000) | (0.031) | ||
BMIZ | Body mass index for-age z-score | − 0.357 | − 0.328 | − 0.403 | 0.075*** |
(1.339) | (1.255) | (1.460) | (0.020) | ||
Overweight | If BMIZ >  = 1, 0 otherwise | 0.149 | 0.144 | 0.156 | − 0.012** |
(0.356) | (0.351) | (0.363) | (0.005) | ||
Age | Years | 14.137 | 14.839 | 13.039 | 1.800*** |
(2.826) | (2.755) | (2.575) | (0.040) | ||
Gender | 1 if boys, 0 means girls | 0.525 | 0.543 | 0.497 | 0.046*** |
(0.499) | (0.498) | (0.500) | (0.007) | ||
Education | Years of education | 7.491 | 8.344 | 6.154 | 2.191*** |
(2.845) | (2.720) | (2.500) | (0.039) | ||
Exercise | Number of exercises per week | 3.280 | 3.550 | 2.856 | 0.695*** |
(3.241) | (3.286) | (3.123) | (0.048) | ||
Household size | Household size | 4.798 | 4.630 | 5.060 | − 0.430*** |
(1.785) | (1.727) | (1.843) | (0.026) | ||
Income | Natural logarithm of the per capita household income(yuan) | 9.072 | 9.350 | 8.635 | 0.715*** |
(1.135) | (1.062) | (1.107) | (0.016) | ||
Urban | I if living in the urban area, 0 otherwise | 0.330 | 0.410 | 0.204 | 0.206*** |
(0.470) | (0.492) | (0.403) | (0.007) | ||
County penetration | Internet penetration rate in local counties | 0.439 | 0.513 | 0.322 | 0.192*** |
(0.270) | (0.254) | (0.253) | (0.004) | ||
Carbohydrate | Natural logarithm of 3-day average: Carbohydrate(g) | 5.455 | 5.433 | 5.482 | − 0.049*** |
(0.382) | (0.387) | (0.375) | (0.018) | ||
Fat | Natural logarithm of 3-day average: Fat(g) | 4.041 | 4.174 | 3.886 | 0.288*** |
(0.558) | (0.496) | (0.587) | (0.025) | ||
Protein | Natural logarithm of 3-day average: Protein(g) | 4.034 | 4.118 | 3.936 | 0.182*** |
(0.363) | (0.347) | (0.357) | (0.016) | ||
Fast food | How many times have you eaten fast food in the last three months? | 1.232 | 1.790 | 0.580 | 1.210*** |
(3.076) | (3.583) | (2.178) | (0.141) | ||
Soft drink | Average liters drink per week | 2.910 | 2.841 | 2.991 | − 0.149* |
(1.663) | (1.512) | (1.822) | (0.078) | ||
Observations | 19, 317 | 11, 791 | 7, 526 | 19, 317 |