Lab 9

Lab 9 Goal

In this lab, all the maps generated using ArcGIS will finally be combined together in the .gif file format – to create an animated file. Not just that – we will also use Arc-to-Earth to create time-lapse animations of the chloropleth maps.

GIF animation

The animations created using GIF files are cool but the downside to them is that the speed at which they transition between layers in the file cannot be controlled beyond their creation.

GIF animations will be done to the following maps:

• Graduated Color (Choropleth) map of Population change in your state(s), 1900-2007
• Graduated color (Choropleth) map of Population change gains and losses (a 2 class map). You will have to go back to ArcGIS and create a new classification (2 classes, split at 0), export, and animate the files.
• Graduated Symbol map of Total Population in your state(s), 1900-2007
• Dot Density map of Total Population in your state(s), 1900-2007

How-to:

1. 1. When exporting maps from ArcGIS, make sure that the maps are exact in their layout so that the resulting animation will not ‘wiggle’.
   2. Add .gif files
   3. Re-order them in order of appearance in the left-hand panel
   4. Set an appropriate speed for web viewers to easily grasp the trend and yet be able to analyze them
   5. Save the file and en joy the animation!

Arc2Earth

Time-lapse animations on Google Earth will be done on the chloropleth, but in two forms:

• Choropleth
• Chloropleth of gains and losses (a 2 class map). For this second map, the first map needs to be modified

In ArcGIS, changes that need to be made to to the chloropleths include:

• Arranging the layers from oldest to newest
• Turn all the layers on
• Change county borders to 3 pt white
• Make sure all the layers in the list are checked.

Using the Arc2Earth feature of ArcGIS, export all layers  and add time information. Un-check legend.

And we are done!

Some funny file type sin

Evaluation of Lab 2: making improvements

The final medium of this project is primarily a computer monitor. However, it may also be viewed as a projected image.

There is indeed limited resolution and screen area for a computer screen. Therefore, it is important to make sure words, symbols and patterns are of sizes large enough and complexities low enough to be visible. We also should ensure that the maps can be viewed in a web browser without the need to scroll around. But since there is a large range of resolutions and screen areas of computer screens, we have to make considerations based on an average computer screen. As such I feel that suggestions to save the map at 72 dpi and at a size that can fit into a browser window are reasonable ones.

The issue of different monitors also cause complexity with the distinction of colors such that it is necessary to design the maps and the web pages containing the maps using basic colors that are easily distinguishable from each other. It seems that a color intensity scale of light-to-dark representing a visual hierarchy from most important to least important works best for a computer screen, the possibility of the web page being viewed as a projected image demands careful thought about the matter.

The projection of the world as a three-dimensional surface onto a flat surface like a map involves distortions of areas, shapes, distances, and directions. Some projections are best for accurate mapping of direction, while some are best for measuring distances, even as they distort both shape and area erroneously. Others do better for representing the world on a single map while compromising on both some shape and area distortion. Depending on what data we want to map as well as the message of our map, the choice of which map projections to use matters because we want to use a projection that does not muddle the message of our map. In this project we need to compare percentage change in population of counties on a regional map the size of two states. For the purposes of the project, shapes, distances and directions are irrelevant, although area should be preserved to not present a wrong idea of average population density in counties. Thus we should choose an equal area projection. The Albers Equal Area Projection is a bonus because when we center it on out two states (Nevada and Utah), the resultant map minimized shape distortion in addition to not having area distortion.

ArcGIS provide a large variety of map projections such that users of the software can choose the projection that best suits the needs of the map that they are creating.

For the web pages in general, it is important to include informative pieces about the page and the project in general, such as the title of the pages with adequate information about what is on the page. However, for web pages, since the title can be easily supplemented with a subtitle, it is possible to include more complicated information on a web page than on a map. In this project, since the animated map will take one web page on its own, the information on that page containing the map should be adequate to help viewers understand the map. For example, the title of the page should specify that the map shows percent population change in counties in Nevada and Utah. Any subtitle for the page should explain briefly what population change represents, and any text on the page after should describe what percent population change tells us and what it does not. The map itself would require a title and a legend to inform the reader about how to interpret the map. There should also be an acknowledgement of the US Census Bureau as the source of population data used in creating the map using ArcGIS software. Perhaps, an inset map showing where in the United States are Nevada and Utah located would help viewers of the map orientate themselves better as well.

Considering that individuals viewing the map generally focus from top left to bottom right, as well as on any part of the page and of the map that stands out, it is important to place elements of the entire page (including the map) at locations from left to right and from top to bottom, that will be read or viewed in order of necessity and importance. Besides that, use of appropriate font colors and placement of elements of the page (to manipulate the visual center of viewers of the web page – usually just slightly top of center) will also help direct the line of sight to the main focus of the web page – the map especially (which should therefore be centred), and the title (which should therefore be on the top left corner of the web page and of the map).

When the element of balance in the web pages is evaluated, I feel that some elements on the pages need to be modified, such as the location of the menu bar. Since the menu bar on the left takes up some lateral space but little longitudinal space on the page, it creates an off-balance and disrupts the visual center of the web pages. I feel that it should be changed into a horizontal bar or moved to the bottom of the web page.

In the design of the web pages to date, there have been some efforts to improve sight lines by placing elements of the web page into grids. Taking into account the possibility that the grid needs to be modified if the menu box is moved from the left to the top or to the bottom of the page, sight lines need to be modified to bring the text and the maps into the center of the web pages. This can be done by placing empty boxes, which may be filled with color, to the immediate left and right of the central bulk of information. Perhaps some consideration can also go to whether there is a need to relocate the title of the web page to the center if a centralized format of grids is to be applied.

Visual elements on web pages in order of importance (from highest to lowest):

• Map or text with the main point of the page
• Immediate explanations or captions to map or to text carrying the weight of the main point of the page (text)
• Color of the section containing the main body of the web page
• Title (text)
• Explanatory subtitle of page (text)
• Menu leading to other web pages that are part of the project
• Color of the section containing the title, the subtitle and the menu
• Additional information that will supplement the immediate information on the web pages (text)
• Documentation of main sources and tools used in the project (text)
• Color the sections immediately adjacent to the main body of the web page
• Segregation between sections of the same web page
• Background color of the web page

Currently, central body of the page is lower in hierarchy than the title and the subtitles. I plan to rectify the problem by changing the color of the title and the subtitle from blue (which stands out on an orange-yellow background) to black. I also plan place regions of darker color immediately adjacent to the central text to highlight the visual center of my web pages more effectively.

Evaluating Labs 3 and 5

Considering that ArcGIS work only with very specific file formats, like DBase and Excel worksheets, it is necessary to transform that original Notepad format that the population data was provided in into DBase or Excel worksheet file formats. DBase being the file format of preference, the event where Microsoft (MS) Office software on the computers being updated to the latest 2007 version created a problem, because the new 2007 version could no longer generate DBase files. To get around the problem, we used alternative software like OpenOffice to create files with DBase formats. File format incompatibilities like this make data processing more tedious but they are not insurmountable obstacles to transforming our population data for it to be map-able using ArcGIS.

For my project, The first file I attempted to append to the attribute table of the layers showing states of Nevada and Utah is of the DBase format, but it turned out unsuccessful because the FIPS codes of counties did not match – the DBase files had FIPS codes in running order instead of in their original values, such that population data cannot be properly matched with the specific counties. Even after rectifying FIPS codes, ArcGIS still could not incorporate population data into the attribute tables of the states of Nevada and Utah. When I eventually switched to using Excel worksheet formats, the problem went away. Still, I am worried that the Excel files might not work seamlessly with ArcGIS.

In mapping the percent change in population of counties, it is essential that the large volume of population data obtained from the US Census Bureau’s website be matched exactly with the data in the attribute tables of the states containing those counties (in ArcGIS). Otherwise, the maps would lose their value.

The entire process of working with file formats while transforming data and importing data to different software, albeit being tedious, was irreplaceable. Through the complexities of data management, the issues of the need for professional responsibility and meticulousness in data processing are highlighted. Although it was time-consuming and occasionally disorienting to learn to process data, it is good to experience to process data, as long as students are allowed time that is in tandem with the level of significance accorded to the object of learning.