Big John

Spatial Representation and Power The Authority of Maps Maps are read as authorities; they are difficult to create and mapmakers have technical skill; people trust what they see in maps But mapmaking is not objective; many choices must be made. What to map and how to map it are choices Culture is embedded in maps, such as ideas about the nature of land and human society Propaganda（宣传；鼓吹） maps are extreme examples Land Areas and Epistemoloty We see maps as evidence of physical world The appear ...

Scale The Concept of Scale Scale is the size or extent of something The temporal scale is the length of time The spatial scale si the physical size or extent Spatial Scale 1. Cartographic Scale The ratio of the distance on the map to the distance in the physical world Three types of Cartographic Scale: Verbal (word) scaleGraphic (scale bar)Representative fraction (RF) WordS describe UNITS of distance on map compare to UNIT of distance in physical world Rarely used outside printed paper map ...

Correlation What is Correlation Two variables are correlated (associated) when their values are not independent Probabilistically speaking Examples: When people by chips they are very likely to buy beer When people have yellow fingers, they are very likely to smoke Variables that are predictive Some variables are predictive because they are correlated with other target variables Smoking and coughing are predictive variables for respiratory disease Cause and Effect A variable v1 is ...

Type I Error false positive, "rejected the null" but there is no difference Rejecting a true null hypothesis Also known as false positive or α\alphaα error Concluding there is a difference when there actually is none Easy to control Decide the probability α\alphaα in advance for a given test The standard cutoff is 0.05, meaning there is a 5% chance of a Type I Error Type two Error false negative, "failed to reject" bull there is a difference Failing to reject a fa ...

Geography The study of the Earth and its systems. inhabitants, and processes Physical Geography: the study of the Earth’s environmental processes Human Geography: the study of people and how their activities vary Environmental Studies: the systematic study of human interactions with the environment (to solve complex problems) Geomatics: the collection, distribution, storage, analysis, processing, and presentation of geographic data or information Urban/Regional Geography Cartography The study ...

What Is GIS? In technology part, GIS is the abbreviation of Geographic Information Systems Computer-based (hardware & software) system that: Create locationally referenced data Stores and organizes locationally referenced data Performs spatial analyses Creates visualizations, usually in map form (but also tables, graphs, dashboards) In theory part, GIS is the abbreviation of Geographic Information Science Theory behind how to solve spatial problems and how to implement GISystems The stud ...

Selection Sort Selection sorting a list of N items: Find the smallest item Move it to the front Selection sort the remaining N-1 items (without touching front item!). Selection sort Code with Java: 1234567891011121314151617181920212223242526272829// Background: Using Selection to sort a String Array// 1. Find the Smallest itempublic static int findSmallest(String[] x, int start){ int smallestIndex = start; for(int i = start;i<x.length;i++){ int cmp = x[i].compareTo( ...

Logic and Probability For Statistics Descriptive Statistics What is a Mean (M) ? Measurement of central tendency Mathematical midpoint (average) of a data set Standard Deviation (SD) SD=∑(X−X‾)2NSD = \sqrt\frac{\sum(X -\overline{X})^2}{N} SD=N∑(X−X)2​​ Measurement of variability How variable is the data How close to the mean is a given value Target of descriptive statistics: Descriptive statistics can be run on the entire target and take a sample is the usually method. Use ...

Lecture2 Note Programs Implement Functions Definition: Function is a type of procedure or routine. Example of function: Inputs and Outputs of Programs Clear what are the inputs of the program and what are the outputs of the program. Program Parameters Parameters are the special inputs, which are the necessary context for the program to run. (But not every program needs prameters) Parameters can be chose by youself or set the program to choose a random parameter or optimize the parameter b ...

lecture1 Note What is Data? Data information that is pocessable by Computer Information is in ditial form A program can read and analyze the information Accessible Data Right to access to the data Procedure to obtain or use the data Option 1: Locally Option 2: Remotely API An API is a doucemnt that specifies what queries are possible and their format, and the format of the responses. ## Licenses for Data Creative Commons provides licenses for data. Followings are details ...