scoring

16 bgbb.PAlive
Arguments
params
x
t.x
n.cal
BG/BB parameters - a vector with alpha, beta, gamma, and delta, in that order.
Alpha and beta are unobserved parameters for the beta-Bernoulli transaction
process. Gamma and delta are unobserved parameters for the beta-geometric
dropout process.
number of repeat transactions a customer made in the calibration period. May
also be a vector of frequencies - see details.
recency - the last transaction opportunity in which this customer made a transaction.
May also be a vector of recencies - see details.
number of transaction opportunities in the calibration period.. May also be a
vector of calibration period transaction opportunities - see details.
Details
x, t.x, and n.cal may be vectors. The standard rules for vector operations apply - if they are not
of the same length, shorter vectors will be recycled (start over at the first element) until they are as
long as the longest vector. It is advisable to keep vectors to the same length and to use single values
for parameters that are to be the same for all calculations. If one of these parameters has a length
greater than one, the output will be a vector of probabilities.
P(alive at n+1 | alpha, beta, gamma, delta, x, t.x, n)
Value
Probability that the customer is alive at the (n+1)th transaction opportunity. If x, t.x, and/or n.cal
has a length greater than one, then this will be a vector of probabilities (containing one element
matching each element of the longest input vector).
References
Fader, Peter S., Bruce G.S. Hardie, and Jen Shang. “Customer-Base Analysis in a Discrete-Time
Noncontractual Setting.” Marketing Science 29(6), pp. 1086-1108. 2010. INFORMS. http:
//www.brucehardie.com/papers/020/
Examples
params