Vocabulary
Statistics Formulas
Problems
Calculator Key Strokes
Bonus
100
The relationship between two variables.
What is correlation?
100
^y= mx+b
What is the equation of a regression line?
100
At the 5% significance level, there is enough evidence to conclude that there is a significant linear correlation between ____ & ____.
What is the rejecting the null hypothesis?
100
STAT EDIT L1= X Values L2= Y Values
How to input X and Y number values into your TI 83/84?
100
State the null and alternative hypothesis
What is the first step when attempting a hypothesis test?
200
Data sets that can be represented in ordered pairs (x,y) X= explanatory Y= response
What are independent and dependent variables?
200
t= r ---- √1-r² ------ n-2
What is the standardized test statistic t?
200
(-2.447, +2.447)
What is the rejection regions of a two tailed test when n=8, r=0.9129 and a=0.05?
200
STAT CALC 2- 2 Vars Stat Scroll down and find each value
How to find Σx, Σy, Σxy, etc?
200
d.f= n-2
How do you find the degrees of freedom?
300
The measure of the strength and the direction of a linear relationship between two variables. r=sample correlation coefficient
What is a correlation coefficient?
300
n∑xy-(∑x)(∑y) _____________ √n∑x²-(∑x)² √n∑y²-(∑y)²
What is r? (correlation coefficient)
300
Σx=15.8 Σy=1634 Σxy=3289.8 Σx²=32.44 Σy²=337,558 r=0.913 strong linear corelation Interpretation= As the amount spent on advertising increases, the company sales also increase
What is the correlation coefficient for the advertising expenditures and company sales from the given numbers, what can you conclude?
300
STAT CALC 2- 2 Vars Stat Enter n=?
What is the key stroke for finding n?
300
α
What is the symbol for level of significance?
400
The sum of the squares of the differences between each predicted y-value and the mean of y.
What is explained variation?
400
√∑y²-b∑y-m∑xy ______________ n-2
What is the modified Se equation?
400
^y= 50.729x + 104.061 x= (1.5) ^y= 50.729(1.5) + 104.061 ^y= 180.155
Whats the advertising expenses, compared to the company sales? *When the advertising expenses are $1500, the company sales are about $180,155*
400
STAT CALC 4- LinReg(ax+b) LinReg y=ax+b a= m b= b
How to find the regression line values m and b?
400
____ variation = ______ variation + _______ variation
What is total=explained+unexplained?
500
The line for which the sum of the squares of the residuals is a minimum.
What is regression line or the 'line of best fit'?
500
n∑xy - (∑x)(∑y) ∑y ∑x ------------------- ----- - m ---- n∑x² - (∑x)² n n
What are the equations for m and b?
500
H0= p >(or equal to) 0 Ha= p < 0 / H0= p <(or equal to) 0 Ha= p > 0 / H0= p = 0 Ha= p (not equal) 0
What is a left tailed, right tailed and two tailed test for a population correlation coefficient?
500
STAT CALC 4- LinReg(ax+b) LinReg(ax+b) L1, L2 LinReg y= ax+b r= 0.935475
How to find the correlation coefficient "r" in your TI 83/84?
500
Table 5 in Appendix B
Where do you find the critical values for chapter 9?
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