Un estado del arte

tels in mind w e, though, that duct will in the 8), p. 59f). How

s, involved ca ustry.

mond / Schues Airlines flight f early-booking alculate the cu quoted in Stift p. 10). Lookin at sold increas gher, when bo

ess importa reluctance orts the hy eisure trave e-scale cann

ss case o

o maximize ecasts. In p oint to decid

capacity fo 3, which is b

of all bookin

tion of book

the prevaili iod as a m for 40% of

which are also t introducing lo

long run also wever, since a rrier) than hot ssler / Axhaus from Novembe ooked at a late

ant than b to select ypothesis th elers are n nibalization ngs are acc

kings and re

ng yield ma means of pr

f the reven

sold by Pricel ow-priced prod o have a negat

airline tickets i tels (location, sen (2007), p.

er 2006. As a engers is sligh nue of the flig st (2009), p. 7 flights of a Nor parture date is er time).

both the fli options w hat flexible no suitable

of revenue

e tickets

ues of a pa n busy fligh

it wants to king high-y booking data cepted in the

evenues (las

anagement rice discrim nue of the

ine, Hotwire o ducts which in tive impact on nvolve more p hotel chain) th 10. The book result of the s tly underrepre ht, is based on 74ff. This is als rth-American a s approaching

ght type ( where the

time-range option for s.⁴⁷⁷

rticular fligh hts, the yie

limit the sal yield busin a of a Swis e last week

st 75 days pr

practices, w ination, the

displayed

or other ‘opaqu n the end are o the price leve potential uncer his argument s ing data is tak selected month esented. The p n the (approxi so in line with airline, he foun

(in spite of th

(direct fligh flight time e tickets, w

most bus

ht, an airlin eld manage

le of low-far ness passe ss Internatio k prior to de

rior to depa

which stron e bookings

flight. The

ue’ channels, of similar qual el of the specif

rtainty (duratio seems less co ken from a Sw h, it is likely to price data, wh imated) values

the data analy nd that the av he fact that the

ht) and the es are not while being iness trips,

ne relies on ment of an re tickets in engers. As onal airlines

parture.

arture)⁴⁷⁸

ngly use the of the last e monetary

several ity than a fied product on, departure onvincing in wiss

importance of late bookers also became apparent in an analysis of fares between Amsterdam and London in spring 2009, which found that “average fares increase by about 3% each day as departure approaches, with a cumulative 80% increase in the last 20 days.”⁴⁷⁹

Given the monetary importance of late bookings, it is not astonishing that airlines are willing to reject low-yield bookings (which usually are placed several weeks earlier) by limiting the amount available low-fare tickets in order to preserve capacity for an expected business demand. However, if the forecast for a high-yield booking class turns out to be too high, which given typical forecast errors (on the booking class level) of up to 25% in the airline business⁴⁸⁰ is often the case, this passenger ‘spill’ results in unused capacity (‘spoilage’) and lost revenues. In this context, flexible time-range tickets would allow airlines to accept more low-fare booking requests than in the current environment by pooling the demand risk of several flights (it is unlikely that the amount of forecasted late-bookings materializes on all flights).

To avoid accepting more bookings than the overall set of flights which are composing a flexible ticket is able to accommodate, airlines could use a fractional booking approach.

This means that if a flexible booking is accepted which builds upon a set of five flights, the booking could be considered as 0.2 passengers in each of the flights booking records. If one of the flights reaches its capacity limit (based on the forecasted bookings corrected for the expected no-shows), the flight is withdrawn from the flexible product set and the fractional booking in the remaining four flights is increased to 0.25 passengers. Once four flights out of the potential flight set are fully booked, the flexible ticket would be switched into a full (1.0) booking on the last remaining flight.

If several flights still have available seats at the defined notification time (e.g. one week prior to departure), the airline could assign the booking to the alternative in the flexible-ticket set which entails the lowest marginal costs, i.e. mainly costs for the additional fuel burn resulting from another passenger, passenger-specific airport fees and catering costs (if applicable). Ceteris paribus (e.g. assuming the same type of aircraft) this would usually imply to assign passengers to a non-stop flight, since these flights minimize the distance flown and avoid the costs of a transfer and an additional flight. From a Yield Management perspective the flight with the lowest bid-price (i.e. the lowest opportunity costs) should be selected.⁴⁸¹

By pooling the risk that more passengers arrive than there is capacity for in all flights of the flexible time-range ticket set and by shortening the forecast horizon (i.e. the time between flight allocation and departure date) as a consequence of the delayed assignment, airlines are able to increase the amount of low-fare tickets sold and the

479 Cf. Alderighi et al. (2011), p. 5

480 Cf. Belobaba / Weatherford (2002), p. 820

481 Cf. also Petrick et al. (2010) for a detailed discussion of various allocation mechanisms

degree of of a flight wit

ure 84: Impa

on, flexible ng condition ere are seve der the comm

ng which t th a high loa

act of flexib

time-range ns are given mand by low

fferings of a e the prese cannot (in t with a netw cause the a n acceptable alization of f h demand

le time rang

e tickets are n on a route

w-yield pas a network c ence of LCC

the long ru work airline c absence of e amount o

ge tickets on

e able to ge of low-fare t h-yield reven

y on the l ure date ap es between

airline grou

e. The res n Figure 84

n optimal ov

enerate a p hich cannot oute led to a

by offering re

ate fences m tickets witho nues.

evel of ind proaches

origin and p.

sulting impa 4.

verbooking

positive con t be profitab an average g traditiona makes it im out having dividual flig e price level al, specified mpossible to to accept a ghts, which n which are e

• At least some flights on the considered route are sometimes subject to a load factor of 100% (otherwise, there is no need to further optimize the available capacity usage).⁴⁸²

A study by Petrick et al. (2010) used OR-techniques to quantify the revenue gains which can be achieved through a delayed assignment of booking requests. They assumed a flexible product which incorporates both non-stop and indirect flights and is sold at a discount of 25% relative to the lowest specified fare. Based on their simulation they came to the conclusion that the gained flexibility in average allows for an increase of revenues by 4%. Furthermore, in line with what has been found above, they specify that

“flexibility is more important to the firm if uncertainty is higher and that a late notification date helps to further increase revenues”.⁴⁸³