- By
**elana** - Follow User

- 88 Views
- Uploaded on

Download Presentation
## PowerPoint Slideshow about ' Wednesday 10-10-12' - elana

**An Image/Link below is provided (as is) to download presentation**

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Wednesday 10-10-12

- Today you need:
- Whiteboard, Marker, Eraser
- Calculator
- 1 page handout

Warm-upNeed a White Board

1. Graph the following equation:

Warm-upNeed a White Board

1. Graph the following equation:

Objectives

- I can use Linear Regression with a calculator to find linear prediction Equations
- I can find the correlation co-efficient “r” for the data

Correlation Co-efficient

- The correlation co-efficient “r” tells how linear the data is.
- Values of 1 or –1 indicate perfect linear lines, either positive or negative
- Values closer to zero mean the data has no linear relationship
- Small whiteboard number line with r=1 and r=-1

Plotting Data

- When the data you plot forms a near linear relationship, then we can use a linear equation to approximate the graph.
- We use what’s called a Best-Fit Line. This line is drawn to be as close to the data points as possible, but may not touch them all.

Using the Calculator (Linear Regression)

- The calculator is a great resource to give us a prediction equation.
- It is more accurate than doing the equation Manually
- We will enter the data into the STAT mode of the calculator

Turn Diagnostics On. 2nd catalog,

arrow to Diagnostic on, enter, enter

Linear Regressions on the calculator:

(you should clear the calculator before beginning)

2nd, +, 7, 1, 2

#1.

Linear Regression

- Finding the equation of your “Best Fit Line”
- STAT, then EDIT
- Enter X-Values in L1, Y-Values in L2
- STAT, then CALC
- Choose (4) LIN REG

The table below shows the years of experience for eight technicians at Lewis Techomatic and the hourly rate of pay each technician earns.

Prediction Equations

- y = 1.234x + 5.574
- Remember:
- x = Experience in Years
- y = Pay rate in dollars
- We can use this to predict other values

When Dealing with Years

- Must modify years starting at “0”
- If you don’t you get a really negative y-intercept value that won’t match the graph
- Example on next slide

If the Independent variable is Years and these are your values

1901

1903

1905

1910

1913

1920

Then these are the values we will actually enter for L1

0

2

4

9

12

19

Inputting YearsHomework

- Linear Regression Ws

Download Presentation

Connecting to Server..