1. LSP 120: Quantitative Reasoning and Technological Literacy
Topic 1: Introduction to Quantitative Reasoning and Linear Models
Lecture 1.1
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Why are we here?
Data: numbers with a context
Cell: each data point is recorded in a cell
Observation: each row of cells form an observation for a subject/individual
Variable: any characteristic of an individual
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Why Data?
1) Data beat anecdotes
“Belief is no substitute for arithmetic.”
Henry Spencer
Data are more reliable than anecdotes, because they systematically describe an overall picture rather than focus on a few incidents .
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Why Data?
2. Where the data come from is important. “Figures won’t lie, but liars will figure.” Gen. Charles H. Grosvenor ( ), Ohio Rep.
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7. Familiarizing with Data
Open Excel
Collect data:
Ask 5 classmates the approximate # of text messages they send per day
Record the data on Excel spreadsheet
Calculate average using the Average function on Excel. (There are many functions such as sum, count, slope, intercept etc. that we will use in this class)
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8. What is a linear function?
Most people would say it is a straight line or that it fits the equation y = mx + b. 
They are correct, but what is true about a function that when graphed yields a straight line? 
What is the relationship between the variables in a linear function? 
A linear function indicates a relationship between x and y that has a fixed or constant rate of change. 
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9. Is the relationship between x and y is linear?
The first thing we want to do is be able to determine whether a table of values for 2 variables represents a linear function. In order to do that we use the formula below:
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To be continued….
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