Gravity is determined by the mass of an object and the distance between that object and the object experiencing the gravitational force. Since the International Date Line is an imaginary line on Earth's surface, it doesn't have any mass of its own, and therefore doesn't influence gravity.

Here are the factors that affect gravity on Earth:

* Earth's mass: Gravity is stronger where Earth's mass is more concentrated.

* Altitude: Gravity decreases as you move further away from Earth's center, meaning higher altitudes have slightly lower gravity.

* Local density variations: Areas with denser rock or higher mineral concentrations can have slightly stronger gravity.

The International Date Line is simply a line of longitude that marks the change from one calendar day to the next. It doesn't affect Earth's mass, altitude, or density, so it doesn't influence gravity.