LDA 150 Final

Three major sources of error in GPS measurement are

Satellite, receiver, atmospheric interference

To create road buffers as a raster, you must start by executing the_________ tool on the vector road layer.

Euclidean Distance

Do you need the internet to use GPS? True or False

True

Tobler's law states that_________.

Values close together are more likely to be similar

A GPS signal consists of

 A navigation message, one or more carrier waves, one or more digital codes

 Map algebra is a technique for_________.

 Analyzing stacks of raster maps using mathematical or Boolean operators

A better spatial interpolation method should have a _____ RMS error.

lower

What raster function would you use to find the areas of a slope raster that exceed 20 degrees?

 Raster Calculator

Estimating values for a new raster between measurements taken at point locations uses the_________ function

Interpolation

You have a point dataset of wells near the ocean, with a field that contains chloride values. You want to create a raster showing the severity of saltwater intrusion using the chloride values. You could use the_________ tool.

 IDW

When does automatic resampling of rasters occur?

whenever two input rasters with different cell sizes are used in a function

Why is it important to store rasters in projected coordinate systems that preserve distance and/or area?

Because many raster tools involve distance and/or area-based algorithms

 Select the definition of the term "reclassify function"

replaces sets or ranges of values in a raster with different sets of values

 The semivariogram demonstrates the degree of dissimilarity between points as a function of separation distance. true or false

true

In a weighted overlay, the weight must sum to 1. true or false

True

 A single dimensionless number called Dilution of Precision (DOP) indicates errors associated with satellite geometry. The lower value of DOP is better. true or false

True

 Which of the following is a stochastic (geostatistical) interpolation method?

 kriging

A higher power for the IDW method means that:

Closer control points will have greater influence on the estimation

 Ideally, all rasters being analyzed are stored in the same projection, extent, and cell size

to avoid the introduction of resampling errors

 Why is it important to ensure that your criteria fit the problem that you are trying to solve?

 The source data, geoprocessing tools, and transformation methods vary based on the way that the criteria is defined.

Which one of the following functions uses a moving window?

Neighborhood Statistics

An analysis mask is used to?

 Screening out regions outside an area of interest by giving the cells no data values

 A cost-distance analysis is used to find.

The easiest path between two locations

 When performing exploratory spatial data analysis, it was determined that the sampled values were not normally distributed. When creating a prediction surface, how could you adjust the semivariogram model in order to meet the normally distributed assumption?

Apply an empirical transformation

Which of the following best describes the primary difference between deterministic and geostatistical spatial interpolation techniques?

Deterministic methods use mathematical formulas, while geostatistical methods are based on spatial statistics.

What is the primary purpose of using cross-validation in geospatial analysis in GIS?

 To validate the model by excluding each input sample point systematically.

 How does the theory of relativity proposed by Einstein influence the functioning of GPS?

By adjusting for the time dilation effects due to the speed of the satellites.

Which code of the GPS signal operates at a frequency of 1.023 MHz?

 C/A Code

Which factor does NOT contribute to satellite errors?

 Attitude Control

 Other satellite-based GNSS systems, other than GPS are:

A) GLONASS

B) Galileo

C) BieDou-3

D) All the above

All the above

 What are some example applications for suitability modeling?

1. Locating optimum habitat for endangered species

2. Locating optimum habitat for a dam

3. Locating optimum habitat for a road

 Why is the L band used to transmit GPS radio signals?

Able to penetrate clouds, fog, rain, storms, and vegetation

Which errors can be eliminated by DGPS?

Satellite clock errors, orbit errors, atmospheric errors

 Explain the different types of suitability modeling

1. Binary: involves a binary final answer → 1 (suitable) or 0 (unsuitable)

2. Weighted: allows for a range of final answers, from 1-10; allows certain layers to have more influence (weight) on the results of the model

3. Fuzzy: assigns membership values to locations that range from 0 (non-membership/unsuitable) to 1 (membership/suitable)

Explain the difference between local, neighborhood, zonal, and global raster operations

1. Local raster operations examine only one single target cell during analysis

2. Neighborhood raster operations examine the relationship of a target cell to proximal surrounding cells

3. Zonal raster operations examine groups of cells that occur within a uniform feature type

4. Global raster operations examine the entire areal extent of the dataset

Describe how the semivariance can be used to quantify the spatial autocorrelation in a data set.

1. Can be used to quantify spatial dependence in a data set bc if spatial dependence does exist in the dataset, known points that are close to each other are expected to have small semivariances and known points that are further apart are expected to have larger semivariance

What are the limitations associated with deterministic interpolation?

1. No clear guidance on how large the radius of influence/neighborhood is

2. No estimate of how good the interpolation is (i.e. no measure of error or uncertainty)