GIS Midterm what you'll actually study

What is remote sensing

Collecting data of earths surface from a distance

what is nominal data

Data divided into categories with no real order

Eg: land use types(forest, urban, agriculture)

Topology map how to find nodes

they are the end points of lines, polygons are made up of lines, they also make up the intersection point

topology map what is left and right polygons

GIS can store what polygons are on the left and right so that shared boundaries are stored once, neighbor relationships are known, and polygon errors are easier to find. it establishes topology, defining how spatial features share boundaries and connect to each other

how to find class/equal interval

max - min / classes and put numbers into that output number range based on classes

What is ordinal data measurement?

Data organized into ranked categories, but the differences between ranks aren't necessarily equal.

Eg: flood risk being low, medium, or high

What is interval data measurement

Numerical data with equal intervals between values but no true zero

Eg: calendar years, as year 0 doesn't represent the absence of time

ratio data measurement

Numerical data with equal intervals that does have a true zero, allowing meaningful comparisons of proportions

Eg: populations, distance or elevation

Easy way to remember different types of data measurement

Nominal = Names

Ordinal = Order

Interval = Equal differences

Ratio = True zero

what is query spatial data?

its a GIS request that selects or filters geographic features, points, lines, or polygons, based on their location or spatial relationship to other features

how to find outcome to spatial join

examine the attribute table and metadata of the resulting output layer

what is a quantile classification

a data shading method that classifies and organizes numerical data into a certain number of classes.
you have 100 things, choose 5 quantile classes, each class will hold 20 things

what are natural breaks

a data classification method that groups similar data values together and make clear distinctions between different classes
eg: mapping counties based on population.
rural counties 1,000-3,000 people

suburban-16,000-18,000 people

urban counties-24,000+

classifying those based on natural population groupings

what are the 3 components of GIS

hardware-physical computer running GIS, including GPS units
software-the programs able to store analyze, and manipulate spatial data
data-the spatial data itself

How to calculate degrees, minutes, and seconds

67* 48’ 25” to degrees
keep 67, divide minutes by 60, divide seconds by 3600, then add together
47.392* to degrees minutes seconds

47 stays the same. 0.392 X 60 then take remainder decimal and multiply by 60 for seconds

map distortions

Simple random sampling

meant to eliminate sampling bias, true random

stratified random sampling

meant to represent all conditions within groups. choosing distinct sub groups with random sampling within those groups

systematic sampling

getting spaced sampling

cluster sampling

getting sampling from groups of people living in the same areas

spatially balanced sampling

probability based servey design that spreads sampling evenly, but randomly

active remote sensing

emits its own energy, its own light source
Radar
LiDar
Sonar

passive remote sensing

detects stuff from the energy of the sun
aerial photography
most satellites
unmanned aerial vehicles(UAVs or Drones)