Logarithmic colour scale in world map

Hi all,

as probably many collectors, I have a few countries with a lot of different coins, and many countries with only a few coins. In my case, Belgium with 155 different types, and no other country with more than 100 different types. This implies that in my world map, half of the usable colours are not used: Belgium is dark red, and more than half of the world is blue or green (the bottom three bins in the colour scale). Even countries with 16 coins are still in the dark green colour.

Would it be possible to implement a logarithmic color scale, so that the spread is a bit more equal ? See e.g. http://stackoverflow.com/questions/20613841/how-to-generate-a-non-linear-colormap-colorbar

mbaes

Here is another idea for a coloring scale - percent of completion for that country by type/year

I think the first idea will be good for collectors like me...
And the Houseofham's would be for all coins' collectors.

I like Houseofham's idea except that it would need to be based on wish list vs have list because everyone seems to have different types that they collect. IE, I don't collect commemoratives or precious metal coins, except in the US, where I do collect the presidentials.

Alan

Cita: "Houseofham"​Here is another idea for a coloring scale - percent of completion for that country by type/year

​Not a bad idea, "IF" all of the coins that have "PROOF" variations included with the circulated varieties, have the proofs removed.

I have several hundred coins that I would never spend the time now money to get the proofs. So therefore, I could theoretically have all known circulating coins but without the proofs, it/they would not be complete without the proofs ...

+1 for logarithmic (it's a problem where everything from 1 to 19 just falls in three bins), disagree for completion (some countries just made far too much stuff, and a big fraction of that is NCLT, and/or patterns aka "non selected trial strikes").

I think the only country I have all the types for is Bohemia and Moravia (4 out of 4), and even for them I'm missing the patterns; and even ignoring patterns, I'm not sure if I will ever complete another country (aside from maybe a few places that only ever made one type, and Saint Pierre and Miquelon, where I have 1 out of 2).

It looks a little better with a logarithmic scale, but if your collection is focussed on a couple of countries then there are still only a few colors used for the rest of the world. I found that if you give the top spots to these countries, then use a logarithmic scale for the rest, the map has many colors and looks great.

Hello,

 

This idea has recently been posted again at https://en.numista.com/forum/topic127783.html

I'm posting my reply here.

 

The color scale is actually already logarithmic in some way, although it is displayed as non-logarithmic to facilitate understanding:

• 1 - 6% : blue
• 6% - 20%: greenish
• 20% - 40%: yellowish
• 40% - 66%: orangish
• 66% - 100%: redish

 

A linear color scale would have been:

• 1 - 20%: blue
• 20% - 40%: greenish
• 40% - 60%: yellowish
• 60% - 80%: orangish
• 80% - 100%: redish

That would have given much more areas in blue for the map of many members.

 

The way I understand the problem (as clearly illustrated by the screenshot from inc7007) is not linear versus scalar scale, but rather the logarithmic base. Should we increase the logarithmic base? Probably not for everyone (or it will mess up the maps from other members), but maybe dynamically based on each collection (so that the map shows as many distinct colors as possible even if one country has much more coins than all others)?

An alternative would be to have a continuous color scale. This way, even if UK has 15 times more coins than any other country, you would still have (minor) variations of blue for the other countries instead a flat blue map.

Without wanting to adversely affect the map for people who like it as it is…

 

I (likely others) have one or two of each foreign coin type, but many duplicates from my home country, and date runs I'm trying to complete for others.

 

Would it be possible to add an option to switch the map between ‘totals’ and ‘types’, as my UK number would drop from 4898 total coins to 302 types, this should add a lot more colour to the map.

 

If I was to be picky, I would prefer to see the total number of coins as is, but base the map colours on types.

inc7007

Would it be possible to add an option to switch the map between ‘totals’ and ‘types’, as my UK number would drop from 4898 total coins to 302 types, this should add a lot more colour to the map.

That's already possible, or am I missing something?

Xavier

That's already possible, or am I missing something?

More colourful when viewed by type… but I prefer to see the number of coins, so never leave it set that way.

So I don't usually see these colours, like I said, minor and picky.

 

The problem being I can look at nicer colours, but without the information I want, or I can see the numbers I want to see, but the map is all blue, just wondering if it would be possible to separate colours from numbers, if altering the scale is going have undesirable effects for other members.

The more logaritmic scale of colours would be usefull for me too:

I have red Australia, orange Canada and UK, few yellow small countries and the whole rest is blue (Queen Elizabeth II coins only).

 

Maybe it could be possible to give to the users the option to choose one of 2-3 different versions of colour scale which best fit to their needs?

One of the variant could be ratio have/wish mentioned above.

Xavier

An alternative would be to have a continuous color scale.

+1

 

The current scale color have 15 grades: 1 blue, 2 greens, 2 yellows, 4 oranges and 6 reds.

Perhaps can be added more grades of blues, blue-greens and green-yellows, or in only one step, a continuous color scale (really a scale with 30 colors can be “continuous” for human eye 😉).

Here is another idea: When you hover over the color scale at the bottom, display a little popup with the count range for that color and highlight all countries with the corresponding color.

 

+1 for logarithmic. I haven't checked the charting engine in use here but in most of them it's a fairly simple thing to implement.

You can see from these charts that show the same data how much smoother the distribution is with a logarithmic scale.

Xavier

 

The color scale is actually already logarithmic in some way, although it is displayed as non-logarithmic to facilitate understanding:

• 1 - 6% : blue
• 6% - 20%: greenish
• 20% - 40%: yellowish
• 40% - 66%: orangish
• 66% - 100%: redish

 

The way I understand the problem (as clearly illustrated by the screenshot from inc7007) is not linear versus scalar scale, but rather the logarithmic base. Should we increase the logarithmic base? Probably not for everyone (or it will mess up the maps from other members), but maybe dynamically based on each collection (so that the map shows as many distinct colors as possible even if one country has much more coins than all others)?

 

An alternative would be to have a continuous color scale. This way, even if UK has 15 times more coins than any other country, you would still have (minor) variations of blue for the other countries instead a flat blue map.

 

The idea of having a dynamic logarithmic base is a good one but I have no idea how you'd analyze the dataset to select the appropriate base, +10 points if you can figure it out!

 

I don't think the continuous scale would help much as the subtle differences in shade would probably be impossible to distinguish anyway.

 

For me it just needs to be a bigger base but I completely understand that what is a good base for me isn't necessarily good for everyone.

jay2001

Xavier

 

The color scale is actually already logarithmic in some way, although it is displayed as non-logarithmic to facilitate understanding:

• 1 - 6% : blue
• 6% - 20%: greenish
• 20% - 40%: yellowish
• 40% - 66%: orangish
• 66% - 100%: redish

 

The way I understand the problem (as clearly illustrated by the screenshot from inc7007) is not linear versus scalar scale, but rather the logarithmic base. Should we increase the logarithmic base? Probably not for everyone (or it will mess up the maps from other members), but maybe dynamically based on each collection (so that the map shows as many distinct colors as possible even if one country has much more coins than all others)?

 

An alternative would be to have a continuous color scale. This way, even if UK has 15 times more coins than any other country, you would still have (minor) variations of blue for the other countries instead a flat blue map.

 

The idea of having a dynamic logarithmic base is a good one but I have no idea how you'd analyze the dataset to select the appropriate base, +10 points if you can figure it out!

 

I don't think the continuous scale would help much as the subtle differences in shade would probably be impossible to distinguish anyway.

 

For me it just needs to be a bigger base but I completely understand that what is a good base for me isn't necessarily good for everyone.

Simply letting the user choose the base would be the simplest option.