bgnbd.Expectation {BTYD}

BG/NBD Expectation

Description

Returns the number of repeat transactions that a randomly chosen customer (for whom we have no prior information) is expected to make in a given time period.

Usage

bgnbd.Expectation(params, t, hardie = TRUE)

Arguments

params

BG/NBD parameters - a vector with r, alpha, a, and b, in that order. r and alpha are unobserved parameters for the NBD transaction process. a and b are unobserved parameters for the Beta geometric dropout process.

t

length of time for which we are calculating the expected number of repeat transactions.

hardie

if TRUE, use h2f1 instead of hypergeo.

Details

E(X(t) | r, alpha, a, b)

Value

Number of repeat transactions a customer is expected to make in a time period of length t.

References

Fader, Peter S.; Hardie, Bruce G.S.and Lee, Ka Lok. “Computing P(alive) Using the BG/NBD Model.” December. 2008. Web. http://www.brucehardie.com/notes/021/palive_for_BGNBD.pdf

See Also

bgnbd.ConditionalExpectedTransactions

Examples

params <- c(0.243, 4.414, 0.793, 2.426)

# Number of repeat transactions a customer is expected to make in 2 time intervals.
bgnbd.Expectation(params, t=2, hardie = FALSE)

# We can also compare expected transactions over time:
bgnbd.Expectation(params, t=1:10)