GEOG 201 Final

T/F: With the raster data model location is stored in the dataset by having an X,Y coordinate pair assigned to each cell in the raster matrix.

False

Given the example raster, assume the cell size is 10 meters x 10 meters.  What is the total area for cells with a value of 10?

1800 square meters

Which of the following statements about the vector GIS model NOT Correct?

Location in a point is stored as one coordinate pair

Location in a polyline is stored as a group of coordinate pairs in sequence

Location in a polygon is stored as a group of coordinate pairs in sequence

Location in a line is stored a group of coordinate pairs in sequence

Location in a polygon is stored as a group of coordinate pairs in sequence

Which of the following is INCORRECT about an feature layer in ArcGIS Online?

With a feature layer you can edit features and attributes

With a feature layer you can display data as a basemap

With a feature layer you can perform queries of a table

With a feature layer you can change the color or size of symbols

With a feature layer you can display data as a basemap

Which of the following CORRECTLY describes Web GIS?

With Web GIS you access files on your computer and create web applications

With Web GIS you need to install software to access web services

Web GIS allows advance analysis and symbolization with web maps

Web GIS is good for collaboration and allows you to access web services

Web GIS is good for collaboration and allows you to access web services

Which of the following is NOT true about Data Enrichment in ArcGIS Pro or ArcGIS Online?

It is a tool that enriches, or adds, information from the census to spatial data.

It can be used to provide an estimate of population for a given polygon (area).

The GIS user needs to collect the demographic data layers themself.

It works by using a GeoEnrichment web service.

The GIS user needs to collect the demographic data layers themself.

Which of the following statements about the vector GIS Model is FALSE?

Information about roads, rivers, and railways is likely to be found in one layer

Records (rows) provide information about different features in a layer

Attribute tables can be joined to provide additional information to layer

Fields (columns) provide information about different attributes of a feature

Information about roads, rivers, and railways is likely to be found in one layer

Which of the following is NOT a characteristic of Web GIS (online GIS)?

Interactive maps and web applications.

Designed to facilitate collaboration (multiple people working with the same data)

Data are web services called feature layers.

Advanced analysis and symbolization for traditional cartography.

Advanced analysis and symbolization for traditional cartography.

Which of the following geographic units most closely approximates a "neighborhood"?

Block Group

Subdivision

Census Block

Census tract

Block Group

vector model

• features are points (x,y pair), polylines (connected x,y pairs), and polygons (closed connected x,y pairs)

• model by geometry and logical association

• model in layers

• attribute table provides information about the features

• rows (record) and columns (field)

• tables can be joined and related on a common field

• suited to features

raster model

• array of cells in rows and columns with numeric cell values

• only one coordinate pair is stored (upper left x and upper left y)

• raster resolution — size of the raster cell for a raster dataset (cell size is the same for all cells)

• coordinate location for all other cells is inferred from stored coordinate pair

• each cell is linked to a number that represents a numeric value or class

• discrete (count data; nominal and ordinal) and continuous (measured/transformed; interval/ratio)

• suited to data

3 Tiers of Client-Server Architecture

• client — device making requests and consuming Web & GIS services

• Web server — software interacting with clients and the GIS Server AND GIS server — software serving special web services and interacting with GIS database

• GIS database server — a database with GIS data

Desktop GIS

• data on your computer, stored in various file formats

• software installed on computer

• limited collaboration

• advanced analysis and symbolization for traditional cartography

Web GIS

• data re webservices called feature layers that are on a web server

• access through a web browser

• allows collaboration

• analysis and symbolization capabilities

• interactive web maps and web applications

Web services used by ArcGIS Online

• ArcGIS Enterprise Server (“in-house” GIS server, server admin experience)

• ArcGIS Online (“cloud” GIS server, server admin knowledge and knowledge of JavaScript not needed)

hierarchy of census units

Nations > Regions > Divisions > States > Counties > Census Tracts > Block Groups > Census Blocks

The map scale for an aerial photo is 1:50,000

The length of a road on the aerial photo is 1.5 inches

What is the length of the road in feet?

6250 ft

T/F: When landscape ecologists talk about "large landscape scale" they are referring to the same concept as large map scale. 

False

Concepts of space

• EX: Where is Mount Rushmore?

• absolute and relative location, distance and direction (from something else), distribution, pattern, density

Tools of representation

• EX: A mental map of how you get home from work every day.

• representations

• mental maps (represent spatial experience) and actual maps (represent context and spatial pattern)

• spatial pattern is a concept; the map is a tool for representing that concept

Processes of reasoning

• EX: Is there a spatial relationship between tree canopy cover and household income?

• spatial interpretation (what does the pattern tell us? why is it the way it is?), spatial problem-solving (what is the travel time tot eh nearest food bank? are the food banks in the right locations?), spatial relationships (is there a relationship between household income and tree canopy?)

Displaying a map of public libraries in the context of population density is an example of...

Tools of representation

You have two layers, Soil Stability and City Lots, and you want to find out what part of city lots are stable and unstable.  Which tool would you use for your analysis?

Intersect

Union

Buffer

Clip

Intersect

The compound query: select STATE_NAME = 'TX' AND POP > 50,000 will...

Select all counties in Texas with a population greater than 50,000

Which of the following is the smallest map scale?

1:500,000

Spatial Problem-Solving is an example of what characteristic of Spatial Thinking?

Spatial ideas

Spatial concepts

Spatial reasoning

Spatial representation

Spatial reasoning

In ArcGIS Online when the Condition statement for a query uses "All of the following are true" as in the example below.  This is the same as what in SQL syntax?

It is the same as using the AND logical operator.

Which of the following overlay operations retains all data from both input layers?

Dissolve

Intersect

Union

Clip

Union

representative fraction

a fraction indicating what is represented on the map in relation to waht is on the ground (real life) — expressed as a ratio (1 unit on the map is equal to x units on the ground, 1:X)

determining RF on a map/aerial image

1. choose a prominent linear feature that you can also measure on the ground

2. measure the linear feature on the photo (your choice of units)

3. measure the linear feature on the ground (actual length) or with a georeferenced map

4. set up the relative fraction, cross-multiply, and convert and cancel units

SQL and Attribute Queries

SELECT <Features>

FROM <Table>

WHERE <Condition>

• Condition is defined by relational operator: =, <>, >, or <

• Can compound queries with logical operators: OR, AND

proximity analysis

geospatial technique that measures distances and spatial relationships between geographic features to support decision-making and planning

intersect operator

• spatial and attribute information from two inputs are combined to create a single output

• the area in common for the inputs is retained in the output

union operator

• spatial and attribute information from two inputs are combined to create a single output

• area from both inputs are retained in output

map algebra

algebra applied to maps

• each new cell value computed from single cell values of input rasters

• often called “cell-by-cell” operations

• division (Input/constant — such as unit conversions)

• additive (such as suitable = precip + elev → ranked locations)

• multiplicative (such as suitable = precip x elev → best location)

• conditional (such as suitable = Con(Precip = 1 and Elev = 1, 1, 0)

• reclassify (continuous range of cell values reclassed into raster of categories)

• zonal statistics (compute summary statistics based on an area or zone)

In developing a research hypothesis "Urban trees are valuable and therefore attract homeowners with income" is what? 

a premise

"Everything is related to everything else, but near things are more related than distant things" is a...

law

How is a scientific law different from a scientific theory?

A law is meant to describe phenomena, while a theory is meant to explain phenomena

You run a Pearson's r correlation test, resulting in r = -0.82 and p-value = 0.03; your alpha is 0.01. What do you conclude?

There is a strong negative correlation but it is not statistically significant

You do GIS analysis and quantify the relationship between the amount of lead in drinking water (parts per million) and race (proportion people of minority ethnicities) by block group.  You calculate Pearson's r correlation coefficient and find the r coefficient is 0.4 and the p-value is 0.1.   Before your analysis you decided to use an significance level of 0.05.  What do you conclude? 

While the correlation is positive it is not statistically significant.

Which of the following is TRUE about simple random sampling? 

Observations are collected at regular intervals.

It involves dividing the geographic area into strata.

There is the possibility that rare or unevenly dispersed phenomena might be missed.

Observations are taken in proportion to the size of the strata.

There is the possibility that rare or unevenly dispersed phenomena might be missed.

Which of the following statements best describes the general process of the scientific method?

Its main goal is to prove theories absolutely true and eliminate all uncertainty.

It involves making observations, collecting data, forming a testable hypothesis, designing experiments or tests, and drawing conclusions.

It primarily relies on personal beliefs and anecdotal evidence to form conclusions.

It is a rigid, linear process that always leads to a definitive, unchanging conclusion.

It involves making observations, collecting data, forming a testable hypothesis, designing experiments or tests, and drawing conclusions.

A tentative statement that suggests a relationship between variables.

hypothesis

A well substantiated explanation or framework.

theory

A descriptive statement that reliably predicts a phenomena.

law

"Urban trees are valuable and attract homeowners with higher income" Why is this not falsifiable? 

It doesn't state the direction of the relationship

Which of the following is NOT true about hypothesis testing in statistics?

Statistical tests tell us whether something is true for false

We never know for certain whether the Null is correct; only the probability it might be

It involves rejecting or not rejecting a null hypothesis

Every statistical test has a null hypothesis

Statistical tests tell us whether something is true for false

For a statistical test, the probability of incorrectly is rejecting the Null Hypothesis is the...

p-value

• the alpha value is the maximum probability of committing a Type I error that we are willing to tolerate

deductive thinking

a type of logical thinking — start with a general premise from which you predict/deduce an outcome to make conclusions (a way of generating knowledge)

scientific method

• based on deductive reasoning

• starts with an observation/question

• then a research topic area

• then a hypothesis

• next testing with an experiment

• then analyze the data

• then report conclusions

• and it cycles back through (ongoing cycle)

developing a research hypothesis

1. research topic (general) → Just Sustainability and green amenities

2. observation/premise → urban trees are valuable and attract homeowners with higher income

3. research question → is there a relationship between household income and urban trees?

4. research hypothesis (testable and falsifiable) → there is a positive relationship between household income and urban percent tree cover

Digital Elevation Model (DEM)

• format more often used in GIS

• a raster (array of cells) wherein each cell holds an elevation value

Triangulated Irregular Network (TIN)

• format that more accurately models complex topographic surfaces

• a network of triangular facets which each contain a value for aspect and slope

• ADVANTAGES (over DEM): complex topographic surfaces, better for modeling ridgelines and slope breaks, file size is smaller

Which of the following statements is FALSE?

An aspect of 360 degrees is a north-facing aspect.

An aspect of 180 degrees is a south-facing aspect.

An aspect of 90 degrees is a west-facing aspect.

An aspect of 0 degrees is a north-facing aspect.

An aspect of 90 degrees is a west-facing aspect.

Which BEST describes how slope is calculated for GIS data?

A moving window calculates slope of the focal cell based on the run and rise in the Y direction

A moving window calculates slope of the focal cell based on the run and rise in both the X and Y directions

A moving window calculates slope of the focal cell based on the run and rise in the X direction

A moving window calculates slope of the focal cell based on the run in both the X and Y directions

A moving window calculates slope of the focal cell based on the run and rise in both the X and Y directions

A 3D model created from LiDAR data showing forest coverage is a __________________.

Digital Surface Model

Which of the following are examples of active remote sensing?  Choose all that apply. 

MODIS Terra

Landsat OLI

SRTM

LiDAR

LiDAR, SRTM

Which of the following is FALSE about LASER used in LiDAR technology? 

It can be transmitted over large distances.

It is comprised of non-visible near-infrared wavelengths.

It travels as a higher velocity than other forms of EM energy.

It is composed of 'coherent' light.

It travels as a higher velocity than other forms of EM energy

Interpret the topographic contours indicated by the straight line. 

Assuming north is at the top of the map, which one of the following statements is TRUE?

This is an area that this flat.

This is a gentle east-facing slope.

This is a gentle west-facing slope.

This is a steep east-facing slope.

This is a steep east-facing slope.

What is a problem encountered with Aspect in GIS analysis?

Aspect is an interval-level measurement but it is circular

Which of the following most accuracy describes active remote sensing

Electromagnetic energy is emitted from the Sun and the sensor records the portion of energy reflected off objects.

Electromagnetic energy is broadcast from a platform and a sensor records the portion of energy reflected off objects.

Electromagnetic energy is actively sought after by the remote sensing device.

All remote sensing is generally considered to be active remote sensing.

Electromagnetic energy is broadcast from a platform and a sensor records the portion of energy reflected off objects.

Removing the above-ground LiDAR data points in a LiDAR point cloud gives you a...

Digital Relief Model

Digital Surface Model

Digital Terrain Model

Digital Elevation Model

Digital Terrain Model

T/F: The first return with LiDAR scanning can be the ground-level. 

True

2D vs. 2.5D vs. 3D

• 2D: flat plane

• 2.5D: 3D terrain, but no above ground structures

• 3D: 3D including above ground structures

slope

measure of change in elevation (rise) with a change in horizontal distance (run)

• DEM derivative

• calculated as percent: (rise/run)*100

• a moving window calculated slope value for focal cells

• can be used to clear up spectral confusion

aspect

compass direction that terrain faces measured in degrees

• DEM derivative

• North (0 or 360), East (90), South (180), West (270)

• can be used to clear up spectral confusion

• can tell us a lot about ecosystems

• cosine and sine transformations provide non-circular interval-level measurements of aspect

LiDAR

Light Detecting And Ranging

• LASER (Light Amplification by Simulated Emission Radiation): composed of “coherent” light, NIR wavelengths, can be transmitted over large distances

• near instantaneous laser footprint, laser pulse may generate single or multiple returns

• terrain and landcover features can be extracted from the cloud of LiDAR point returns

• DSM: contains elevations of first reflective surface (first return)

• DTM: contains elevations of ground/terrain surface (objects subtracted)

Which of the one of the following statements about a Generative Adversarial Network (GAN) model is FALSE?

It is typically used for creating very realistic (but artificial) images, videos, or audio.

It uses two ANN that compete with one another until a "realistic" solution is achieved.

It can be used to create an "aerial photo" of a completely fictional place.

It uses ANN to learn from a very large corpus of textual data.

It uses ANN to learn from a very large corpus of textual data.

In an Artificial Neural Network (ANN) which layer defines the patterns in the data?

Hidden layer

Which type of AI could be used to generate realistic but fictious aerial photo?

General Adversarial Network

If you didn't know how to do something in a GIS software and you wanted some help with step-by-step instructions, what type of AI would help you most? 

a Large Language Model

T/F: Although Large Language Models (LLMs) and Generative Adversarial Networks (GANs) appear to use logical (deductive) reasoning, the are really predicting based "seeing patterns" in extremely large training datasets (i.e., inductive reasoning). 

True

Machine Learning

algorithms learn from data and predict…

Deep Learning

Artificial Neural Networks (mimics the human brain)

Generative AI

Highly advanced NN (generates “new content”)

• Generative Adversarial Networks (GAN) — imagery, audio, video, “Deep Fakes”

• Large Language Models (LLM) — ChatGPT, Gemini, CoPilot, Chatbots

ANN

computational model that looks for patterns in large amounts of data

• input layer — raw training data

• hidden layer — connections/patterns in the data

• output layer — prediction/output

GAN

computational model generated output through “adversarial” process

• aim to create something new

• generator NN — takes input image and tries to generate something new

• discriminator NN — uses training data to critique what the generator produces

• competition between two networks continues until something realistic is produced

LLM

computational model using a single, massive neural network

• self-supervised learning — LLM predicts the next word in a sequence based on massive corpus of texttual information

• generative but also transformer

GeoAI

the application of artificial intelligence fused with geospatial data, science, and technology

• remote sensing and image classification

• predictive spatial analytics

• teaching and learning (pedagogy)