According to the Numbeo , entry in the survey is saved as the number in the range [-2, +2], with -2 having meaning of strongly negative and +2 meaning of strongly positive.
The survey is filtered to eliminate potential spam, like people entering the large amount of data which are differentiating from the median value.In the present survey result, a scale [0, 100] is used for the values since it is easier to read for users.Most of the data are based on perceptions (opinions) from visitors of this website. For pollution section, the survey include some relevant data from World Health Organization and other institutions.
Pollution Index is an estimation of the overall pollution in the city. The biggest weight is given to air pollution, than to water pollution/accessibility, two main pollution factors. Small weight is given to other pollution types.
Pollution Exp Scale is using an exponential scale to show very high numbers for very polluted cities, and very low numbers for unpolluted cities. Therefore to calculate formula it uses the exponential function to calculate the index.
Pollution in Accra, Ghana
|Air Pollution||87.50||Very High|
|Drinking Water Pollution and Inaccessibility||81.25||Very High|
|Dissatisfaction with Garbage Disposal||98.44||Very High|
|Dirty and Untidy||90.62||Very High|
|Noise and Light Pollution||82.14||Very High|
|Water Pollution||93.33||Very High|
|Dissatisfaction to Spend Time in the City||85.29||Very High|
|Dissatisfaction with Green and Parks in the City||96.67||Very High|
Purity and Cleanliness in Accra, Ghana
|Air quality||12.50||Very Low|
|Drinking Water Quality and Accessibility||18.75||Very Low|
|Garbage Disposal Satisfaction||1.56||Very Low|
|Clean and Tidy||9.38||Very Low|
|Quiet and No Problem with Night Lights||17.86||Very Low|
|Water Quality||6.67||Very Low|
|Comfortable to Spend Time in the City||14.71||Very Low|
|Quality of Green and Parks|
Bellow is the 2017 latest World ranking on Pollution Perception Index by Numbeo.