A general rule of thumb is that if your economic model has no value judgements, it's positive economics, and if it does have value judgements it's normative economics, since to tell someone what he ought to do, you first have to judge what is best for him.
A subscriber identity module or subscriber identification module (SIM) is an integrated circuit that is intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers).
Other information contained in a SIM card is the IMSI or International Mobile Subscriber Identity, Local Area Identity or LAI, ICCID and etc. A cell phone or mobile device can only be used once it is inserted with the SIM card.The important factor to be taken account is that the SIM card is only functional once it is inserted into the mobile device.However, once activated SIM is the conduit for tracking as it will emit the IMEI number of your mobile device as well as the SIMâs serial number to a nearby cell tower.he important factor to be taken account is that the SIM card is only functional once it is inserted into the mobile device. However, once activated SIM is the conduit for tracking as it will emit the IMEI number of your mobile device as well as the SIMâs serial number to a nearby cell tower.