Final Review

Question 1

Attribute vs. standalone table

Answer 1

Attribute tables contain the nonspatial information about a geographic feature.

A stand-alone table is a table of attributes that do not have associated geographic features.

Question 2

1.Name column is a:
2.and it’s associated value is:

Answer 2

1.Field or attribute
2.Record

Question 3

Field types for: Name, Salary, Job Type, Age

Answer 3

Text, long integer, text, short integer

Question 4

Data types for: Name, Salary, Job Type, Age

Answer 4

Nominal, ratio, categorical, ratio

Question 5

Similarities between Join and Relate

Answer 5

They are both temporary (easily removable) relationships which combine tables based on similarities.

Question 6

Differences between join and relate

Answer 6

Cardinality: Join is one to one/many, relate is many/one to many

Table created: Join is a unified table, relate is a linked table (selections on one affect the other)

Question 7

Target vs Source table

Answer 7

Target is usually on left, having join/relate performed on it, Source is opposite.

Question 8

One record on the right selects four on the left, what is the cardinality?

Answer 8

Many to one, join

Target to source

Question 9

Common field for join/relate is

Answer 9

A shared field between two tables, abbreviations/different spellings of the same field can still work (State Name Vs. States). Cannot use Shape, look for upper right asterisk maybe?

Question 10

What is SQL

Answer 10

Structure Query Language, used for selections. It is case sensitive.

Question 11

Spatial query

Answer 11

Selects features based on spatial relationship between target and source layer

Question 12

Spatial relationships between features

Answer 12

Intersect, contain, proximity (Select by feature)

Question 13

Most important component of spatial queries

Answer 13

Differentiating target and source layer and determining their relationship

Question 14

Select all counties a highway passes through?

Answer 14

Intersect, target layer is counties and source is highway.

Question 15

All buildings within HB county and all capitals within 500 miles of nuclear cities. Target/source as well.

Answer 15

Contain, target is building source is HB county
Proximity, target is capitals and source is nuclear cities

Question 16

Intersect vs Union

Answer 16

Intersect can combine any vector feature with any other vector feature and only includes overlapping areas. Union combines polygons together as they are without excluding any area.

Question 17

Erase vs Clip

Answer 17

Erase removes all overlapping areas involved, clip removes all but the overlapping areas involved.

Question 18

Append vs Merge vs Dissolve

Answer 18

Append attaches features into an existing feature class without creating a new feature class. Merge allows features with different attributes to be combined to create a new feature class. Dissolve combines all bordering features with each other to make larger, simpler features without boundaries.

Question 19

What is editing?

Answer 19

Create new features or shapefiles from scratch based on raster sources and remote imagery or tweaking existing features/shapefiles.

Question 20

Topology and why it is important for vector features

Answer 20

The spatial relation between features which allows for use of specific tools and accuracy in vector data.

Question 21

Spatial relationships in same layer

Answer 21

Connectivity, adjacency and intersection (digitization).

Question 22

4 Common topological errors

Answer 22

Dangling (undershooting or overshooting the intersection point between two lines), gaps between polygons and overlapping polygons.

Question 23

How to minimize topographical errors

Answer 23

Turn on map topography and snapping.

Question 24

Snapping

Answer 24

Avoid dangles between lines and polygons, set minimum distance for snapping using snapping tolerance.

Question 25

Snap types

Answer 25

Point, end, edge and vertex.

Question 26

How to create adjacent polygons simply

Answer 26

Auto complete or split polygons

Question 27

Digitization steps

Answer 27

Create a feature class, set its geometry, set its datum to project’s datum, turn on edit and start tracing features.

Question 28

What tool to use for creating curved segments

Answer 28

ArcSegment

Question 29

Editing tips

Answer 29

Save edits every 5 minutes, turn on layer being edited, use data instead of layout view.

Question 30

What is Geocoding?

Answer 30

Pinpointing an address on a map using xy values by comparing layers to be geocoded with a reference layer/address locator.

Question 31

How does google maps calculate a route in steps

Answer 31

1. Search address 2. Pinpoint address on map (geocoding) 3. Uses network analysis to find shortest route 4. Displays results

(Uses geocoding and network analysis)

Question 32

The geocoding process in 4 steps

Answer 32

1. Start with address to be geocoded 2. Have reference layer/address locator 3. Use Geocode tool to match address 4. Inspect values, good is 80-100, tied is 60-80.

Question 33

Arcgis World geocoding services vs creating your own locator

Answer 33

World geocoding services are fast and ready to use, apply to 106 countries, require credits and an internet connection. Making your own locator is free, no internet required and able to be used anywhere, but much more complex and time consuming.

Question 34

Address matching process in steps

Answer 34

1. Parses address to be geocoded into several components 2. Standardizes abbreviations such as E. And East 3. Compares each component with the reference layer 4. Evaluates closeness of each component and assigns score based on match with reference layer 5. Assigns highest value component as the final point on map.

Question 35

Vector Data

Answer 35

Points, lines, and Polygons, include topology.
Advantages: 1) compact data structure, 2) topology, perform the network analysis 3) used in discrete features, points, polylines, polygons, preserve the spatial accuracy of these discrete features.
Disadvantages: 1) it is a complex data source; 2) for the topology, we have to consider the connectivity between the neighboring polygons; 3) is not efficient to represent the continuous feature (elevation)

Question 36

Raster data

Answer 36

(cells = grids, cell size= spatial resolution, JPEG, TIFF, PNG files are all raster data) (Also smaller cell size means higher spatial resolution) No topology, larger sizes like 2GB.

Question 37

What is NoData? Is it zero?

Answer 37

NoData is a cell which doesn’t have any data, different from zero and will result in any multiplications yielding NoData. Not included in analysis.

Question 38

As cell size increases…

Answer 38

Spatial resolution decreases, details decrease, processing speed increases and file size decreases.

Question 39

Maximum and minimum of inputs calculation

Answer 39

Max will use the largest cell size involved in a calc, min will take the smallest.

Question 40

Union of inputs vs intersection of inputs

Answer 40

Just like normal union/intersection but with raster.

Question 41

Local

Answer 41

Cell by cell basis

Question 42

Reclassify

Answer 42

Converts raster cell values into newly assigned values based on defined conditions.

Question 43

Boolean

Answer 43

Like reclassify but just 1 or 0

Question 44

Boolean and vs or

Answer 44

And requires two or more values to be true (1), to give a final true value to a cell. Or independently displays both values if they are true.

Question 45

Focal

Answer 45

Neighboring cells involved. (Block stats, slope, aspect, viewshed)

Question 46

Zonal

Answer 46

Larger collections of cells, zones can be entirely disconnected from one another. (Mean, median, majority)

Question 47

Global

Answer 47

Involves all cells in a raster. (Min, max, sd)

Question 48

Euclidean distance vs. buffer analysis

Answer 48

Both measure proximity to a feature, but buffer is for vector, Euclid is for raster.

Question 49

Range

Answer 49

Max - min