Posted by: dmconroy | May 5, 2009

Mitchell 2,3,4

Why map where things are?

By looking at the distribution of features on the map rather than individual features you can see patterns that better help you understand the area you are mapping. This can influence where you should take action or where changes are most need or would be most effective. Patterns can be seen and identified

Deciding what to map

For each individual set of data, certain types of symbols and representation may be more appropriate or effective for the set.

-You can use point features- to map where crimes occur, or to map where different types of crimes occurred.

How will you use the map is an important factor

The audience of the map is sometimes the most important part of deciding what to show and how to show it

– The amount of detail in a zoning map would matter depending on if you are presenting the information at a city council meeting to discuss the location of heavy industry would be different than if you are presenting information about overall zoning patterns in the city

– The way the map is presented also affects the amount of information included. In some cases reference points like roads and waterways can be useful

If the map is able to present the information clearly, you may be able to identify patterns in the data

People map where the most and least are to find places that meet their criteria and take action or to see the relationships between places

By mapping the patterns of features with similar values you’ll see where the most and least are. This can help you decide how to best present the quantities to see the patterns on the map.

Mapping density can show you where the highest and lowest concentrations of features are. Density maps are effective for identifying patters rather than specific points or individual features.

You can create a density map based on features summarized by defined area, or by creating a density surface.

Posted by: dmconroy | May 5, 2009

Mitchell 2,3,4

Why map where things are?

By looking at the distribution of features on the map rather than individual features you can see patterns that better help you understand the area you are mapping. This can influence where you should take action or where changes are most need or would be most effective. Patterns can be seen and identified

Deciding what to map

For each individual set of data, certain types of symbols and representation may be more appropriate or effective for the set.

-You can use point features- to map where crimes occur, or to map where different types of crimes occurred.

How will you use the map is an important factor

The audience of the map is sometimes the most important part of deciding what to show and how to show it

– The amount of detail in a zoning map would matter depending on if you are presenting the information at a city council meeting to discuss the location of heavy industry would be different than if you are presenting information about overall zoning patterns in the city

– The way the map is presented also affects the amount of information included. In some cases reference points like roads and waterways can be useful

If the map is able to present the information clearly, you may be able to identify patterns in the data

People map where the most and least are to find places that meet their criteria and take action or to see the relationships between places

By mapping the patterns of features with similar values you’ll see where the most and least are. This can help you decide how to best present the quantities to see the patterns on the map.

Mapping density can show you where the highest and lowest concentrations of features are. Density maps are effective for identifying patters rather than specific points or individual features.

You can create a density map based on features summarized by defined area, or by creating a density surface.

Posted by: dmconroy | May 5, 2009

Schuurman 4,5

4- Bringing It All Together: Using GIS to Analyze and Model Spatial Phenomena

This section discusses the significance and power of GIS. Mitchell uses the example of the

Cadastral system– historically used to store survey definitions of property lots, land tenure, property values and taxation rates, roads and their condition, zoning information, utility routing, and public recreation areas.

The development of GIS allowed land managers to look beyond just simple lines and look at things like the percentage of home owners within 1000 meters of a green space of library.

GIS is distinguished from cartography by its ability to analyze data

It can use overlay analysis and varies depending on whether vector or raster data is displayed

Buffers are frequently used to identify the boundaries around a certain spatial object that should be considered in analysis. Buffering is used to extend overlay analysis.

5- Where Do I Go From Here? GIS Training and Research

GISystems and GIScience are closely related but not equivalent. They are different but mutually dependent.

GIS data analysis and GIS research are two different things. Universities tend to stress the potential for abstract application of GIS and its ability to solve a broad range of issues but this does not always commensurate the practical application or technical training that is necessary to be hired in a real world GIS job.

The chapter then goes on to review Epistemology and Ontology which is decided to skip over.

Posted by: dmconroy | May 5, 2009

Schuurman 2,3

2; GIS vs Human Geography

This chapter discusses the various ways in which these two disciplines and how they have interconnected over the years

Epistemology- methods that we use to study the world, and the lenses that they entail.

The perspectives that are developed and used to examine data and material

Ontology- What something really is, its foundational essence

There has been the recognition that the application of GIS can be used throughout society. Mitchell discusses various ways in which they can and have been applied.

3; The Devil is in the Data: Collection, Representation, and Standardization

The beginning of this chapter discusses the importance of the data that is collected for GIS analysis. The information can be applied in social and political situations and explains the social significance of digitally inscribed data.

The section about the politics of the data was most interesting to me. This section was personally relevant and I was able to discuss this subject with one of my PG professors and discuss the types of things I was learning in this class. I learned the importance of GIS and how it is able to be applied in various situations.

Posted by: dmconroy | May 5, 2009

Final Evaluation

Class Readings

Week 1

Interesting Apps.

Schuurman ch.1

Week 3

Mitchell ch. 1

Schuurman 2&3

Week 5

Schuurman 4,5

Mitchell 2,3,4

Week 6

Mitchell 5,6 no notes

Tutorials- 3, 4, 5, 6, 7,

– I did not summarize some of the chapters. I had to review the majority of the chapters when I was learning various techniques in order to complete the midterm.


Presentation– presented with Todd Ufferman

Delaware Data Inventory

Project Postings

interesting/helpful sites, rainwater regulations



Posted by: dmconroy | March 4, 2009

ArcGIS:Chapters 6, 7

Chapter 6: By the end of the exercisei started to recoginze what I was doing. When I started the exercise I was unclear on some of the terminology but as the exercises progressed I started to figure it out. I think being able to label different features and attributes of the layers in different ways is a useful tool. In this exercise I started to see how maps can be minipulated to show  specific information and alter the ways they are shown.

Chapter 7:  I ran into some problems when I first started this exercise. I did not have the same cities labeled that the tutorial was asking me to select. I tried to figure out what was wrong but I ended up moving on to another exercise.

Posted by: dmconroy | March 2, 2009

Delaware Data

Address Pts.– This is a visual representation of all the address points located in delaware county. They used existing maps including street maps to further enhance the quality of the adress points and as a good starting point.

Annexations-  A data set containing all of Delaware County’s annexations since 1853 to present. This helps locate annexations and conforming boundary lines.

Archeological- This map shows important historical/archeological sites within Delaware County. It is just a point and does not actually mean anything. This map would make more sense if the points actually meant something.

Bench Marks- These gps points were used to create an orthophoto of delaware county which are effective for measuring true distances because they show and accurate topography.

Building Outline-  This outlines all buildings in Delaware County and can help enhance the property appraisal process.

Census Block- A polygon shapefile that outlines the blocks in Delaware as determined by the Census Bureau.

Census Block Group-  This data seat is a grouping of the block census from the previous set.

Census Tracts- This is the largest grouping of the census information.(a larger grouping of the previous 2 sets.)

Farmlots- This set is used to idenify all of the farmlots in Delaware County according to the US Military and the Virginia Military Survey Districts.

Floodplain 100 Year-  This shows the 100 year floodplain of streams flowing through Delaware County.

Floodplain 500 Year-  This shows the 500 year floodplain of streams flowing through Delaware County. This set is smaller than the 100 year but includes the same streams.

Floodways- A polygon image of the areas that compose the flood pathways across the County.

Historical Local – There is no real data associated with these sites but they show some sort of important historical point in Delaware County.

Historical National-  These are just points on a map. They represent some significant National historical point of interest.

Hydrology-  This map shows the major water ways in Delaware County.

Hydrology Detailed-  This is a more detailed version of the waterways in Delaware County.

Landmarks- This shows specific landmarks and  points of interest in Delaware County including golf courses, schools, churchs, parks and firestations. (including others)

Municipalities – This was created to aid in identifying the municipal boundaries in Delaware County.

Natural Heritage ODNR-  These are points of natural interest in Delaware County as determined by ODNR. (rare or endangered plants or animals, and important natural habitats)

Orthophoto 2008- There are various orthophoto layers. They show an accurate, to scale aerial image of Delaware County.

Parcels- This map shows all 362 mapsheet layers which provide a detailed image of the land parcels in Delaware County.

Precincts- Outlines all of the voting precints in the County with information from the Delware County Board of Elections. This set includes polling locations and City Wards.

Public Land Survey System-  A polygon system depicting the boundaries of the two public land survey systems. (The US Military and the Virgina Military Survey District)

Railroad- Shows each rail line running through the County.

Road Center Line-  All roads in Delaware County.

Road Right of Way- Shows the road right of way for each road.

School Districts- Outlines the area that each school district covers.

Soils- Outlines the soil types for the County

Subdivisions- This shows the boundaries of the subdivisions of Delaware County.

Tax Districts – This layer contains all the individual tax districts withing the county.

Topography – This file contains all of the topography data for the enitire county; the topo shape files are separated into individual township files.

Townships – This data layer shows the township boundaries for the county.

Townships Historical – This data layer displays the original 18 townships in the county.

Watersheds – This map layer displays the watershed areas in the county.

Wetlands – A map layer showing the wetland areas within the county.

Woodland – A map layer displaying the woodland areas in the county.

Zip Codes – A map layer that displays the zip code boundaries in the county.

Zoning – This layer ontains current and historical zoning boundaries for the city of Delaware.

 

 

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Posted by: dmconroy | February 23, 2009

ArcGIS: Chapter 5

This was an enjoyable exercise. The color features are cool to play around with and will be fun to use when i make my own maps. At first the amount of data seemed overwhelming, but the tutorial continued on to show how we can apply the changes to all of the features.

I have also found myself becoming more comfortable with the program and have noticed that i am already understanding what to do as a progress through the exercise. These skills will be useful when i return to my summer work.

Posted by: dmconroy | February 23, 2009

Getting to Know ArcGIS: Chapter 4

Another thrilling tutorial. Similar to the first, this was a simple and straightforward exercise. I do like that they are starting out easy so it is not too furstrating trying to get to know the program. I think that this chapter will be useful and i am now glad i know how to drag files from the ArcCatalog. This seems like it will be useful when we start to use some of the delaware data.

Posted by: dmconroy | February 20, 2009

Mitchell Chapter 1

What is GIS Analysis?

Frame the question: it is important to be as specific as possible when considering your question. This will help decide how to approach the question, which method to use, and how to present the results.

Understand your data: the type of data you use will often determine that methods you use.  But, if you need to use a specifc method, you may need to obtain additional data. It is important to understand whta you have and what you need.

Choose a method: there is often more than one way to obtain your data and some methods may be quicker and give you more approximate data, while others will take longer and give you more specific information. The method you use may be dictated by the type of information you are trying to obtain.

Process the data:  once you have the data you need, you will need to use the appropriate steps in GIS.

Look at the results: the results may be displayed in a map and values in a table or chart. You will have to decide what information to display on your map and how to best present the information. It is also important to look at the results and then you can determine whether they are relevent or useful.

Types of Geographic Features represented on maps:

Discrete features: the location can be pinpointed. at any given location the feature is either present or not.

Continuous phenomena:  this type of feature is seen in precipitation or temperature maps. This feature often starts as sample points such as irregularly placed weather stations.

Features Summarized by Area: examples can be the number of businesses in a zip code, the total length of streams in each watershed or the number of households in each county.

Geographic features can be represented in the GIS using two models of the world: vector and raster.

Categories: groups of similar things that are put together to help the reader understand the data better.

Ranks: puts features in order from high to low or vise versa

Counts: this shows total numbers for each individual data points such as the amount of employees each company in a city employs.

Ratios: relationships between two quantities such as the average number of people per household.

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