Desarrollo de Modelos de Distribución de Especies

The conceptual definition of brand loyalty used in this study is the one proposed by Brown (1952) which defines brand loyalty as a deliberate prior tendency to purchase a brand, often stemming from positive past experiences with its use. Kahn and Meyer (1989) support this definition claiming it closely mirrors modern views on the subject. For all loyalty related measures (average time spent listening, share of category requirements and exclusive audience) the associated propositions state that they will be virtually the same for all stations with a small downward DJ trend and that the measure will correlate with market shares. This means that all stations with a similar market share will have similar loyalty measures. The DJ effect predicts that a small

station, when compared with a large station, will suffer twice in that less people will listen to it and those that do listen will do so for shorter time periods (e.g. McPhee 1963, Ehrenberg et al. 1990).

Average Time Spent Listening

With both fast moving consumer goods and industrial products average purchase frequencies are very similar from brand to brand. Thus Proposition 2 asserts that if radio listening behaviours followed similar patterns, then the average time spent listening to each station will be very similar from station to station, but that there would be a small downward DJ trend in line with market share. Also, the average time spent listening would strongly correlate with market share if proposition two is to be supported.

However, Ehrenberg (1975) notes that average purchase frequency is not exactly constant across brands, but the variation in it is relatively small across brands (e.g., within +/- 10%). Looking at the data related to this phenomenon, it can be seen, from Tables 18 and 19 that the average time reportedly spent listening for all the stations is similar from brand to brand, although some stations are outside Ehrenberg’s +/- 10% band. And, there does seem to be a clear DJ effect in line with market share. The correlation between market share and average time spent listening for ‘All Stations’ was 0.75, r2 = 0.58 and for the ‘Top Twelve’ Stations the correlation was 0.86, r2 = 0.75 indicating a rather good fit.

Although diaries showing supposedly ‘impossible’ listening scenarios (e.g. listening over 20 hours per day) were discarded, there were four stations: The Rock, National Programme, Newstalk ZB, and The Coast, who between them had a total of 22 listeners who reported listening for periods in excess of 12 hours per day. When those 22 listeners were omitted from the analysis, the average time spent listening for those stations became: The Rock 7.4, National Programme 8.4, Newstalk ZB 8.3, and The Coast 6.1. When this adjustment was made the correlations for ‘All Stations’ increased to 0.81 and for the ‘Top Twelve Stations’ to 0.87.

Nonetheless, even with the inclusion of those outlying heavy listeners it is clear that Proposition 2 can be judged as supported. That is, the average time spent listening to each station is very similar from station to station with a small downward DJ trend, and the average time spent listening strongly correlates with market share.

Share of Category Requirements

Share of category requirements (SCR) is the most common measure of brand loyalty used by market researchers (Bhattacharya, Fader, Lodish and Desarbo 1996) and is also used extensively in Dirichlet analysis (e.g. Uncles et al. 1994, 1995; Ehrenberg et al. 2004). As used in this study SCR simply measured each station’s market share among the listeners who listened to that station during the time period in question. Moreover, as market share is calculated among ‘triers’, SCR captures the notion that a listener can be loyal only to a station after she/he has listened to it; which is one of the key underpinnings of Brown’s (1952) loyalty definition.

On the other hand, in a marketing intensive environment (e.g. radio station survey periods), listening-based measures such as SCR fail to reflect whether a particular listening period is attributable to a deliberate prior tendency stemming from positive past experiences with the station, or instead to promotional or situational conditions that prevailed at the time the listening occurred. In other words, did the listener switch stations due to the influence of a promotional message, or because they changed location; or perhaps did a third party change the station - thus causing the listener to effectively change stations?

As can be seen from Tables 18 and 19 the average time spent listening to the radio is typically far higher than the average time spent listening to a particular station (on average 3 to 4 times higher). This ratio naturally gives a low SCR (e.g. for ‘All Stations’ 6.4/23.7= 27%). In looking at the observed SCR’s we see that every station has a low SCR (below 40%), and that all are close to the average, with a slight double jeopardy effect. Whilst these low SCR’s are reflective of the fact that the exclusive audience are light listeners, they also highlight that most listeners are multi-station listeners (refer to Table 20).

As well as proposing that each station’s SCR would be low, Proposition 3 states that, as with cumulative audience and average time spent listening, share of category requirements would vary with market share. The correlation between market share and share of category requirement for ‘All Stations’ was 0.79, r2 = 0.62 and for the ‘Top Twelve Stations’ the correlation was 0.89, r2 = 0.79. When the 22 outliers are removed from the analysis, the correlation for ‘All Stations’ was r = 0.88 and for the ‘Top Twelve’ Stations 0.90. These correlations strongly support Proposition 3.

Exclusive Audience

The final loyalty-related measure is that of exclusive audience - or those respondents who, during the selected time period, report listening to just one station. From a radio industry perspective station managers see specific formats as one way of differentiating their station from their competitors (Eastman, Fergusson and Klein 2002). In so doing they hope that somehow this will increase their exclusive audience. Thus, it is assumed that, for instance, Classic Hits listeners would behave differently from More FM listeners, and listeners to each station would rarely listen to another. This section examines Proposition 4 which states that; each station’s exclusive audience will be small; that the exclusive audiences will be light radio consumers; and that in aggregate the exclusive audience will strongly correlate with market share. The exclusive audience and their average time spent listening (see Tables 18 and 19) are almost constant across all stations--although a slight double jeopardy effect does seem present. For instance, More FM’s exclusive audience is 7%. The proportion of listeners listening just to the lower share Classic Hits is slightly less, whereas at the higher share Newstalk ZB it is slightly more. Also, for all stations, the exclusive audience listens less frequently than the average listener; just an average of 11.8 hours per week, compared with an average listener’s 23.3 hours. The few oddities that exist (The Edge) seem to be the exception rather than the rule, and could be due to factors such as sampling variation or outliers. In the case of The Edge there was one exclusive listener who claimed to spend over 8 hours per day listening to that station. The raw data shows the average number of exclusive listeners per station to be 10 and even the top ranked station had only 33 solely loyal listeners.

As with cumulative audience, average time spent listening and SCR, the exclusive audience was expected to vary with market share. The correlation between market share and exclusive audience for ‘All Stations’ was 0.31, r2 = 0.10 indicating a poor fit. On the other hand, the correlation for the ‘Top Twelve’ Stations the correlation is 0.83, r2 = 0.68 – indicating a reasonable fit. The prime reason for the poor fit between the market share and exclusive Audience for ‘All Stations’ primarily rests with Radio Rhema (22.2%) which may be due to the additional sampling variation associated with a small station, or the unusual listening patterns associated with its religious format.

The key observations from the exclusive audience are clear: there are very few exclusive listeners, they are very light listeners – that is on average an exclusive listener spends just 11.8 hours listening to the radio compared to a polygamous listener who spends almost twice that time (23.3 hours). Also from a station’s marketing perspective--not very important in terms of the station’s overall audience. This supports Proposition 4.