Table 2. Open in new tab Effect of...

	All hours	Morning peak	Evening peak	Off- peak	Weekends
(a) Moderate phase
PYP (moderate)	−0.008	−0.037	−0.052	0.006	0.062
	(0.066)	(0.066)	(0.076)	(0.089)	(0.130)
Observations	9,999	825	1,249	2,875	707
R²	0.654	0.637	0.600	0.483	0.735
(b) Drastic phase
PYP (drastic)	0.180	0.131*	0.154	0.167	0.067
	(0.147)	(0.077)	(0.164)	(0.199)	(0.092)
Observations	10,873	1,418	1,404	2,805	780
R²	0.708	0.607	0.680	0.593	0.730
p value of hyp. testing:	0.121	0.046**	0.124	0.228	0.487
\|${H_0}:\ {\beta_{drastic}} - {\beta _{moderate}} \le 0$\|
\|${H_1}:\ {\beta_{drastic}} - {\beta_{moderate}} > 0$\|

All hours

Morning peak

Evening peak

Off- peak

Weekends

(1)

(2)

(3)

(4)

(5)

(a) Moderate phase

PYP (moderate)

−0.008

−0.037

−0.052

0.006

0.062

(0.066)

(0.076)

(0.089)

(0.130)

Observations

9,999

825

1,249

2,875

707

R²

0.654

0.637

0.600

0.483

0.735

(b) Drastic phase

PYP (drastic)

0.180

0.131*

0.154

0.167

0.067

(0.147)

(0.077)

(0.164)

(0.199)

(0.092)

Observations

10,873

1,418

1,404

2,805

780

R²

0.708

0.607

0.680

0.593

0.730

p value of hyp. testing:

0.121

0.046**

0.124

0.228

0.487

|${H_0}:\ {\beta_{drastic}} - {\beta _{moderate}} \le 0$|

|${H_1}:\ {\beta_{drastic}} - {\beta_{moderate}} > 0$|

	All hours	Morning peak	Evening peak	Off- peak	Weekends
(a) Moderate phase
PYP (moderate)	−0.008	−0.037	−0.052	0.006	0.062
	(0.066)	(0.066)	(0.076)	(0.089)	(0.130)
Observations	9,999	825	1,249	2,875	707
R²	0.654	0.637	0.600	0.483	0.735
(b) Drastic phase
PYP (drastic)	0.180	0.131*	0.154	0.167	0.067
	(0.147)	(0.077)	(0.164)	(0.199)	(0.092)
Observations	10,873	1,418	1,404	2,805	780
R²	0.708	0.607	0.680	0.593	0.730
p value of hyp. testing:	0.121	0.046**	0.124	0.228	0.487
\|${H_0}:\ {\beta_{drastic}} - {\beta _{moderate}} \le 0$\|
\|${H_1}:\ {\beta_{drastic}} - {\beta_{moderate}} > 0$\|

Table 2.

Open in new tab

Effect of Moderate and Drastic Restrictions on CO Concentration

	All hours	Morning peak	Evening peak	Off- peak	Weekends
	(1)	(2)	(3)	(4)	(5)
(a) Moderate phase
PYP (moderate)	−0.008	−0.037	−0.052	0.006	0.062
	(0.066)	(0.066)	(0.076)	(0.089)	(0.130)
Observations	9,999	825	1,249	2,875	707
R²	0.654	0.637	0.600	0.483	0.735
(b) Drastic phase
PYP (drastic)	0.180	0.131*	0.154	0.167	0.067
	(0.147)	(0.077)	(0.164)	(0.199)	(0.092)
Observations	10,873	1,418	1,404	2,805	780
R²	0.708	0.607	0.680	0.593	0.730
p value of hyp. testing:	0.121	0.046**	0.124	0.228	0.487
\|${H_0}:\ {\beta_{drastic}} - {\beta _{moderate}} \le 0$\|
\|${H_1}:\ {\beta_{drastic}} - {\beta_{moderate}} > 0$\|

	All hours	Morning peak	Evening peak	Off- peak	Weekends
	(1)	(2)	(3)	(4)	(5)
(a) Moderate phase
PYP (moderate)	−0.008	−0.037	−0.052	0.006	0.062
	(0.066)	(0.066)	(0.076)	(0.089)	(0.130)
Observations	9,999	825	1,249	2,875	707
R²	0.654	0.637	0.600	0.483	0.735
(b) Drastic phase
PYP (drastic)	0.180	0.131*	0.154	0.167	0.067
	(0.147)	(0.077)	(0.164)	(0.199)	(0.092)
Observations	10,873	1,418	1,404	2,805	780
R²	0.708	0.607	0.680	0.593	0.730
p value of hyp. testing:	0.121	0.046**	0.124	0.228	0.487
\|${H_0}:\ {\beta_{drastic}} - {\beta _{moderate}} \le 0$\|
\|${H_1}:\ {\beta_{drastic}} - {\beta_{moderate}} > 0$\|

Source: Data from RMCAB. Author’s calculations.

Notes: This table shows PYP estimates from five regressions for the moderate restriction (panel (a)) and five regressions for the drastic restriction (panel (b)). The dependent variable is carbon monoxide (CO) in logs. PYP (moderate) is an indicator variable equal to one after August 18, 1998, and zero otherwise. PYP (drastic) is an indicator variable equal to one after February 6, 2009, and zero otherwise. All specifications are fitted along a polynomial time trend of degree five and include meteorological variables, indicator variables for month of the year, day of the week, and hour of the day. Interactions between weekends and hour of the day are added only in the “all hours” model. Standard errors, in parentheses, are robust to heteroscedasticity and arbitrary correlation within one-week clusters. Estimates marked

*p < 0.10,

**p < 0.05,

***p < 0.01.

This Feature Is Available To Subscribers Only