Methodology for performance measurements
The sources
Sources refer to a market player who carries out independent tyre comparison tests, based on a stable methodology and broad performance criteria, to provide objective results for a range of similar tyres according to the type of use.
Only the sources that respect the criteria are included in the base. These criteria are also applied for every test source.
The sources used to establish the performances for a tyre are:
A detailed list of the sources (not including Regulation (EC) 1222/2009) used to rate each product accompanies the display of test ratings.
The structure of the ratings
The final rating is divided into 9 basic performance criteria, and an additional 4 criteria for winter tyres.
The basic criteria are grouped into 5 performance categories: 3 for summer tyres, and 2 for winter tyres.
Within these categories, each performance criterion is weighted differently according to its importance.
The performance categories and the basic performance criteria are as follows:
The methodology for the calculation
All basic performance criteria are rated according to the following principle:
If the source uses its own rating (when it is not on a base of 10), a linear transcoding is performed
The final score for the basic performance is the arithmetic average of the scores obtained for each test.
Note: Tests conducted by car magazines or specialised bodies generally cover the most common tyre sizes available on the market. Even if performances vary slightly depending on sizes, we have chosen to apply the rating to all sizes for a tyre model.
The star rating system
The stars give a graphic overview of the score for a performance category. They are given according to the following scale:
* MOBS : Methodology to calculate the most widely observed label values
rezulteo score
The scores for all of the basic performance criteria are compiled to make 3 ratings for Economy, Comfort and Safety.
These ratings are calculated by weighting the basic performance criteria:
For winter tyres, the overall tyre rating is calculated from the Economy, Comfort and Safety ratings as well as the Ice and Snow ratings.
An overall score can therefore be attributed by weighting the 3 different ratings previously calculated, plus the 2 winter ratings for winter tyres. This weighting is calculated based on the tyre size category: economic, high performance or sports.
Value for money sorting
The price-performance sorting is calculated on the basis of the ratio between the Rezulteo Score and the lowest price found. Tyres are ranked in descending order of this ratio.