Method for predictive pacing of calls in a calling system

Claim 1

A method of automatically selecting and dialing customer telephone at a paced rate and keeping a plurality of agent stations at full occupancy, comprising: providing a database containing telephone numbers to be called; providing a computer for controlling the pacing of telephone numbers to be called connected to said database; providing an automatic call distribution system for dialing the telephone numbers and establishing connection to the customer telephone and connected to said computer; providing a plurality of agent stations connected to said computer and to said automatic call distribution system; determining the maximum number, K, of calls to be in progress at any time by calculating the maximum number, K, such that an average number, Q, of calls waiting in a queue does not exceed a selected delay, DMAX; initiating a new call only when there are less than K calls existing; and for a set up state determining the number, NQ, of calls waiting in queue from the maximum permissible number, QMAX, of calls waiting in queue less a known number, NS, of calls dialed and waiting a response; determining the probability P(NS) of having exactly NS calls in the set-up state from P(NS)=e.sup.(-R*S) (R*S).sup.NS /NS where R is the rate of connection to agents and S is the average call set-up time, setting QMAX equal to a large value; determining the average number, Q, of calls waiting in queue from ##EQU1## determining the average delay D, in queue from D=Q/R; decreasing QMAX and recalculating Q until D exceeds DMAX; and determining the value, K, from K=QMAX+M.

Claim 2

A method of automatically selecting and dialing customer telephone at a paced rate and keeping a plurality of agent stations at full occupancy, comprising: providing a database containing telephone numbers to be called; providing a computer for controlling the pacing of telephone numbers to be called connected to said database; providing an automatic call distribution system for dialing the telephone numbers and establishing connection to the customer telephone and connected to said computer; providing a plurality of agent stations connected to said computer and to said automatic call distribution system; determining the maximum number, K, of calls to be in progress at any time by calculating the maximum number, K, such that an average number, Q, of calls waiting in a queue does not exceed a selected delay, DMAX; initiating a new call only when there are less than K calls existing; and for a set up state determining the number, NQ, of calls waiting in queue from the maximum permissible number, QMAX, of calls waiting in queue less a known number, NS, of calls dialed and waiting a response; determining the probability P(NS) of having exactly NS calls in the set-up state from P(NS)=e.sup.(-R*S) (R*S).sup.NS /NS where R is the rate of connection to agents and S is the average call set-up time, setting QMAX equal to a large value; determining the average number, Q, of calls waiting in queue from ##EQU1## determining the average delay D, in queue from D=Q/R; decreasing QMAX and recalculating Q until D exceeds DMAX; and determining the value, K, from K=QMAX+M.

Claim 3

A method of automatically selecting and dialing customer telephones at a paced rate and keeping a plurality of agent stations at full occupancy, comprising: providing a database containing telephone numbers to be called; providing a computer for controlling the pacing of telephone numbers to be called connected to said database; providing an automatic call distribution system for dialing the telephone numbers and establishing connection to the customer telephone and connected to said computer; providing a plurality of agent stations connected to said computer and to said automatic call distribution system; determining the maximum number, K, of calls to be in progress at any one time by calculating the maximum number, K, such that an average number, Q, of calls waiting in a queue does not exceed a selected delay, DMAX; initiating a new call only when there are less than K calls existing; and for a set-up state determining the number, NQ, of calls waiting in queue from the maximum permissible number, QMAX, of calls waiting in queue less a known number, NS, of calls dialed and waiting a response; determining the probability P (NS) of having exactly NS calls in the set-up state as a function of a rate R of connection to agents and of an average call set-up time S; determining the average number, Q, of calls waiting in queue as a function of the rate R, the set-up time S, the maximum number K and a selected large value QMAX; determining the average delay D, in queue from D=Q/R; decreasing QMAX and recalculating Q until D exceeds DMAX; and determining the value, K, from K=QMAX+M.

Claim 4

A method of automatically selecting and dialing customer telephones at a paced rate and keeping a plurality of agent stations at full occupancy, comprising: providing a database containing telephone numbers to be called; providing a computer for controlling the pacing of telephone numbers to be called connected to said database; providing an automatic call distribution system for dialing the telephone numbers and establishing connection to the customer telephone and connected to said computer; providing a plurality of agent stations connected to said computer and to said automatic call distribution system; determining the maximum number, K, of calls to be in progress at any one time by calculating the maximum number, K, such that an average number, Q, of calls waiting in a queue does not exceed a selected delay, DMAX; initiating a new call only when there are less than K calls existing; and for a set-up state determining the number, NQ, of calls waiting in queue from the maximum permissible number, QMAX, of calls waiting in queue less a known number, NS, of calls dialed and waiting a response; determining the probability P (NS) of having exactly NS calls in the set-up state as a function of a rate R of connection to agents and of an average call set-up time S; determining the average number, Q, of calls waiting in queue as a function of the rate R, the set-up time S, the maximum number K and a selected large value QMAX; determining the average delay D, in queue from D=Q/R; decreasing QMAX and recalculating Q until D exceeds DMAX; and determining the value, K, from K=QMAX+M.

Claim 5

A method of automatically selecting and dialing customer telephones at a paced rate and keeping a plurality of agent stations at full occupancy, comprising: providing a database containing telephone numbers to be called; providing a computer for controlling the pacing of telephone numbers to be called connected to said database; providing an automatic call distribution system for dialing the telephone numbers and establishing connection to the customer telephone and connected to said computer; providing a plurality of agent stations connected to said computer and to said automatic call distribution system; providing a plurality of queues each with assigned agent stations for servers to service calls; providing sets of dynamic variables which are measurements of current call performance for each queue, average server hold time, average call set-up time, rate of connection of calls to servers, and average number of calls in the delay queue; providing a set of dynamic variables which are the current number of agents signed-in at agent stations to serve each queue; determining for each queue the maximum number, K, of calls to be in progress at any one time based upon an iterative algorithm which uses the dynamic variables and calculated probabilities for the numbers of calls in various call set-up states; and initiating a new call only when there are less than K calls existing.

Claim 6

A method of automatically selecting and dialing customer telephones at a paced rate and keeping a plurality of agent stations at full occupancy, comprising: providing a database containing telephone numbers to be called; providing a computer for controlling the pacing of telephone numbers to be called connected to said database; providing an automatic call distribution system for dialing the telephone numbers and establishing connection to the customer telephone and connected to said computer; providing a plurality of agent stations connected to said computer and to said automatic call distribution system; providing a plurality of queues each with assigned agent stations for servers to service calls; providing sets of dynamic variables which are measurements of current call performance for each queue, average server hold time, average call set-up time, rate of connection of calls to servers, and average number of calls in the delay queue; providing a set of dynamic variables which are the current number of agents signed-in at agent stations to serve each queue; determining for each queue the maximum number, K, of calls to be in progress at any one time based upon an iterative algorithm which uses the dynamic variables and calculated probabilities for the numbers of calls in various call set-up states; and initiating a new call only when there are less than K calls existing.