Nutritional balance of kinds of yogurt
Perezgonzalez assessed the nutritional balance of yogurt in 2011 (see b2,c3,d4,e5,f6,g7,h8,i9). The same data can be analysed further, to ascertain whether features such as having children as the target customer may (unintentionally) inform about the overall nutritional balance of above products.
Illustration 1 collates information per group, namely group sizes, as well as medians and interquartile ranges for nutritional balance (BNI). Illustration 2 collates information about mean ranks per group, as well as tests for equality of ranked distributions for independent groups (Mann-Whitney U tests and equivalent Z areas).
|Illustration 1: Group size, medians & interquartile ranges|
|n||median||( IQR )||n||median||( IQR )|
|Children||315||90.50||( 15.67 )||27||100.91||( 11.63 )|
|(Medians closer to 0.0 indicate greater balance)|
According to these results, it can be concluded that:
- Yogurts grouped according to having children as their customer base or not show ranked group distances so extreme that, under normal circumstances, such distances would only occur about 2 times in 100. As yogurts not targeted to children have a lower median BNI (90.50) than yogurts targeted to children (100.91), it can be inferred that yogurts not targeted to children are more balanced nutritionally13. Indeed, the absence of such targeted marketing alone would identify some 12% of more nutritionally balanced yogurts (see rho values in illustration 3).
|Illustration 2. Mann-Whitney U tests|
|Kind||m.rank 'no'||m.rank 'yes'||U||Z||( p )|
|Children||167.97||212.63||3142.0||-2.25||( .024 )|
|(Mean ranks closer to 0.0 indicate greater balance. Sig ≤ .05, 2-tailed)|
Illustration 3 collates information about a regression model for assessing the potential usability of this kind of grouping. The regression model (R, 'enter' procedure) retains the 'targeted to children' category as a significant variable, capable of identifying the nutritional balance of about 12% of yogurts in the sample. The 'usability' of such regression model for predicting the nutritional balance of yogurts not in the sample is, approximately, 11% (adjusted R).
|Illustration 3. Regression model on ranked BNI|
|rho||( p )||β||( p )|
|Children||.122||( .024 )||.122||( .024 )|
|R =||.122||( .024 )|
|(Dependent variable = BNI. Sig ≤ .05, 2-tailed)|
Jose D PEREZGONZALEZ (2012). Massey University, Turitea Campus, Private Bag 11-222, Palmerston North 4442, New Zealand. (JDPerezgonzalez).
Want to know more?
- BNI™ journal (2012, issue 1) - Yogurts galore
- This issue of the Balanced Nutrition Index™ journal collates all BNI™ nutrition information for the original sample in a single book. You can also access information about each individual breakfast cereal on the BNI™ database and aggregated information on Wiki of Science (nutritional balance of food).
- Wiki of Science - Nutrition topics
- This Wiki of Science page provides access to a variety of nutrition topics, including research related to the one described above.