Elementary Statistics

Question 1

Regression

Answer 1

Making a line on the graph. This line shows correlation between 2 variables.

Question 2

What does a regression line predict?

Answer 2

The increase or decrease in y when x is changed by one unit

Question 3

What is y=b^0+b^1x?

Answer 3

Regression line formula to predict a value of y:

y = b^0+b^1x?

For slope: b^1 = r (sy/sx)
For y intercept: b^0 = y-b^1 x

Y= predicted value of y 
B^0= y intercept 
B^1= slope
X= actual value of any x

Question 4

What does standard deviation mean?

Answer 4

Standard deviation tells us how close the data is to the mean. A higher s means numbers are more spread out. A lower s means the numbers are closer together. Remember to calculate s you use the mean.

Question 5

What information do you need for a box and whisker plot?

Answer 5

Upper extreme: highest number
Lower extreme: lowest number
Median: middle number 
Upper quartile: median of upper half
Lower quartile: median of lower half

Question 6

What is the interquartile range or IQR?

Answer 6

Q3 - Q1 = IQR

Question 7

What are outliers?

Answer 7

They are far to one side or the other. If a number is below Q1-1.5 IQR or above Q3+1.5 IQR it is an outlier.

Question 8

How do you find relative frequency?

Answer 8

Frequency divided by n (number of addens in sample)

Question 9

Predicting a value based on other values

Answer 9

Y=ax+b
Y= The prediction (answer)
a= the slope (aka m on the website)
x= the number in the question 
b= the y intercept