Mastering Correlation Coefficient and Line of Best Fit with TI 84

This video tutorial teaches how to use a calculator to find the line of best fit and the correlation coefficient. It begins with an introduction to these concepts, followed by a survey example where students' homework time and GPA are analyzed. The tutorial explains how to enter data into a calculator, calculate the line of best fit, and interpret the correlation coefficient, highlighting the relationship between the variables.

What is the primary purpose of the line of best fit?

• To identify outliers in a data set

• To find the average of a data set

• To calculate the median of a data set

• To determine the relationship between two variables

Tags

CCSS.8.SP.A.2

What does the correlation coefficient (r) indicate?

• The average value of the data

• The total number of data points

• The strength and direction of the relationship between two variables

• The difference between the highest and lowest values

Tags

CCSS.HSS.ID.C.8

How many students were surveyed in the example provided?

• Twenty

• Three

• Five

• Ten

Tags

CCSS.6.SP.B.5A

What were the two questions asked in the survey?

• How many hours do you sleep? and What is your GPA?

• How many minutes do you spend on your homework? and What is your GPA?

• How many hours do you study? and What is your favorite subject?

• How many minutes do you spend on your homework? and What is your favorite subject?

Tags

CCSS.RI.6.7

CCSS.RI.7.7

CCSS.RI.9-10.7

CCSS.RL.8.7

CCSS.RL.9-10.7

What should you do if there are existing numbers in the list before entering new data?

• Skip entering new data

• Turn off the calculator

• Highlight the list and press clear and enter

• Delete the entire list

Tags

CCSS.6.SP.B.5A

Where do you enter the x values in the calculator?

• In L2

• In L3

• In L1

• In L4

What is the format of the equation provided by the line of regression?

• y = cx + d

• y = bx + a

• y = ax + b

• y = mx + c

What should you do if the correlation coefficient does not show up in the calculator?

• Turn on the diagnostic feature

• Reset the calculator

• Re-enter the data

• Turn off the calculator

Tags

CCSS.HSS.ID.C.8

How do you turn on the diagnostic feature in the calculator?

• Go to second and then catalog, scroll to D, and select diagnostic on

• Press the reset button

• Enter the data again

• Turn off the calculator and turn it on again

What does an r value of 0.933 indicate?

• No correlation

• A strong correlation

• A weak correlation

• A negative correlation

Tags

CCSS.HSS.ID.B.5