Pacing algorithms are typically the number one factor in determining agent productivity.

Pacing algorithms are the processing logic which determines the rate at which calls are made by the dialer.  Pacing algorithms generally vary in the timing of dial attempts relative to agent availability.  The choice of pacing algorithm is best understood as selecting a tradeoff between agent productivity and the quality of interactions with your targeted audience.

Predictive dialing algorithms are fairly aggressive pacing algorithms, that utilize predictive dialing techniques to provide a high level of agent productivity.  However, nuisance calls can occur as a side effect of predictive dialing.  Nuisance calls may impact the quality of contacts with your targeted audience, and therefore the effectiveness of your agents, as discussed below.  A good predictive algorithm will be able to achieve high levels of agent talk time, with a minimum of nuisance calls.  Most dialers will also provide options for directly or indirectly controlling how aggressively predictive dialing techniques are applied.

Preview dialing is another prominent pacing algorithm, which provides the agent with call data before placing the call, and provides for high quality interactions.  With time to absorb information such as name, address, payment history, etc, the agent is well-prepared to make the most of each dialogue.  Preview dialing also does not have some of the side effects of predictive dialing, such as abandoned calls and "dead air".  While preview dialing provides for high quality interactions with the targeted audience, any gains in agent productivity are dramatically lower than can be achieved with predictive dialing.

There are numerous pacing algorithms available on the market, with variations from dialer to dialer in terms of implementation details, control options to tweak or manage the algorithm, and even the meaning of a particular algorithm.  When considering a dialer, it's important to understand what these pacing algorithms actually mean for that particular dialer, and the rate at which the dialer paces dial attempts while maintaining an acceptable quality of interactions.  Depending on the pacing algorithm and the specific dialer implementation, this rate may be partially dependent on other factors listed below, such as the number of agents and dynamics of any answering machine detection.  In combination with the other factors listed below, the rate of dial attempts will be key in determining the productivity of your agents.