The following description is based on the 2017 median household income of counties in New Mexico.
The first map created was based on the equal interval approach. Four categories were created for this map. The categories are as follows: incomes below $47,092, between $47,092.50 and $68,125, $68,125 and $89,157.50, and greater than $89,157.5. Based on the map as seen below 26 of the 33 counties had median household incomes below $47,092.50, with 6 of them with incomes between $47,092.50 and $68,125, and 1 above $89,157.50. There was no county with a median income between $68,125 and $89,157. Based on the map, the majority of the counties live below the median household income of the U.S. Furthermore, because median household income of all counties is $46,715 and is below the national income, this indicates that the state as a whole is relatively poor, with only 5 counties living above the national average.
The second map was based on the quartile approach. For this map, 4 categories were created with an outlier. The four categories that were created were: incomes between $26,000 and $31,000, $31,001 and $35,000, $35,001 and $42,000, and $42,001 and $110,000. Based on the map, it appears that 8 counties lie between $26,000 and $31,000, 8 between $31,001 and $35,000, 8 between $35,001 and $42,000, and 9 between $42,001 and $110,000. There is also one outlier which is Los Alamos at $110,190. Based on the map, it appears that the counties with different incomes are scattered across the state with no exact patter.
The two maps show that ,depending on how data is presented and categorized, different conclusions can be made.