Free listing: a method to gain initial insight of a food category Daniela Ferraris and Guillermo Hough

Transcription

1 Free listing: a method to gain initial insight of a food category Daniela Ferraris and Guillermo Hough DESA-ISETA (6500) Nueve de Julio Buenos Aires- ARGENTINA Tel/Fax: (02317) guillermo@desa.edu.ar

2 Nueve de Julio

3 Introduction and summary results

4 Free Listing is a deceptively simple but powerful technique (Bernard, Russell Research Methods in Anthropology) In Free Listing you ask informants to list all the X you know about or inquire what kinds of X are there? X might be: - Cookie brands - Movie stars - Main meals -OR

5 FRUITS year-old adolescents 84 from low-income families 100 from middle-high income families Please list all the fruits you know whether you ve eaten them or not whether you like them or not Each one was given up to 15 minutes to complete their list

6 Adolescent listing all the fruits she knows

7 water bergamot medlar persimmon pomegranate water bergamot sour water persimmon tuna pomegranate water water sour mango sour mango papaya SUBJ5 SUBJ4 SUBJ3 SUBJ2 SUBJ1 Crude list from 5 subjects

8 Transformed list showing position of each fruit for 5 subjects. This matrix is used to calculate summary stats and the distance matrix Fruits mentioned by 25% of the subjects FRUITS raspberry pomegranate lemon fruit kumquats water SUBJ SUBJ SUBJ SUBJ SUBJ

9 Summary Income Minumum number listed Maximum number listed Average number listed Low Middle/high

10 % consumers who mentioned each fruit Only fruits mentioned by > 10% subjects low medium water lemon raspberry water lemon fruit rasberry kumquats mulberry mango sour_ pomegranate medlar

11 Average order of each fruit in the list Only fruits mentioned by > 10% subjects low medium water mango sour_ fruit pomegranate rasberry lemon mulberry kumquats medlar

12 Core set of items Most mentioned Banana Pear Orange Grape Melon Apple Kiwi Peach Strawberry Water Mandarin Average listing order Apple Banana Orange Pear Mandarin Peach Strawberry Kiwi Grape Melon Water These can be used for a future study on degree of liking or frequency of consumption Both lists coincide

13 Cluster Analysis and Multidimensional Scaling

14 SUBJ1 SUBJ2 SUBJ3 SUBJ4 The distance between items in a freelist can give glimpses of the underlying cognitive structure of the domain The difference in rank between two fruits would provide a natural measure of the distance between them in the mind of each subject pomegranate water bergamot papaya mango sour tuna pomegranate water mango sour water water persimmon medlar

15 water kumquats fruit lemon pomegranate raspberry SUBJ4 SUBJ3 SUBJ2 SUBJ1 FRUITS Distance matrix: - Euclidean - Cityblock: provided better interpretation

16 mulberry lemon rasberry

17 Multidimensional scaling Including fruits mentioned by > 10% consumers Stress= 0.19 Including fruits mentioned by > 25% consumers Stress= 0.15 Limit of acceptability (Borgatti, 1996)

18 Low-income adolescents water fruit pomegranate lemon kumquats 0.0 appl e -0.5 rasberry

19 Low-income adolescents Stone-pulpy Big-watery Commoneveryday?? Berries Odd-to-eat Fruit? Seasonal water rasberry pomegranate kumquats lemon fruit appl e

20 1.5 Medium/high income adolescents water lemon fruit kumquats mulberry rasberry

21 Middle/high income adolescents Berries? Odd-to-eat Fruit?? In Argentina s are so big they look like s Same- family Big-watery Common citrus Commoneveryday? fruit mulberry rasberry kumquats lemon water appl e

22 Conclusions Summary results: Differences between populations in number of items listed Core members of a category: listed by most respondents or items that were first mentioned MDS and Cluster Analysis: Show up associations between members of a category

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