Basic Probability
Imagine we’re playing a cool board game, and we rolled an 8-sided dice, what is the sample space for this experiment?
1, 2, 3, 4, 5,6 7, 8
Out of all vanilla survey participants, what was the chance that they liked the flavor?
7/26 = 0.27
If we got a r value of 0.566, how could we interpret this value?
Moderate positive linear relationship
If you saw a graph where as X increased Y increased as well, there must be a _______ correlation
Positive
A company audit showed that of 875 bills that were sent out, 623 were paid on time, 155 were
paid up to 30 days late, 78 were paid between 31 and 90 days late, and 19 were paid after 90
days. One bill is selected at random. What is the probability that the bill was paid on time?
623/875 = .712
Imagine we’re playing a cool board game, and we rolled an 8-sided dice, P(3 or even) = ?
5/8 or 0.625
Out of all Pisatchio survey participants, what was the chance that they liked or disliked the flavor?
13/26 = 0.5
If we got a r value of -0.969, how could we interpret this value?
Strong negative relationship
If you saw a graph where as X decreased Y increased as well, there must be a _______ correlation
Negative
The P(A) = .17 and P(B) = .49. If the P(A or B) = .58, are A & B mutually exclusive?
No! 0.17 + 0.49 does not equal 0.58
Imagine we’re playing a cool board game, and we rolled an 8-sided dice, P(2) = ?
1/8 or 0.125
For strawberry survey participants, if we use a cutoff of 0.05, is it unusual for someone to like the flavor?
6/26 = 0.23, No it is not unusual because 0.23 > 0.05
If someone had a GPA of 2.50, what could we predict their hours spent playing video games to be?
12 hours
If you saw a graph where as X increased Y increased sometimes and decresed sometimes as well, there must be _______ correlation
No
Give the regression equation.
y = 38.45 – 0.09x
Imagine we’re playing a cool board game, and we rolled an 8-sided dice, P(2^C) = ?
7/8 or 0.875
Out of all pistachio and strawberry survey participants, what was the chance that a selected participant would be neutral to their flavor?
23/52 = 0.442
What is the correlation coefficient?
-0.969
The ___ I attend class, the less friends I make. Therefore, there is a negative correlation between these 2 variables.
Give the correlation coefficient
r = -0.88
Imagine we’re playing a cool board game, and we rolled an 8-sided dice, P(3 or 4 or 5) = ?
3/8 or 0.375
What is the probability that a randomly selected participant liked vanilla?
7/78 = 0.090
Compute the least-squares regression equation for the given data set. Round the slope and y-intercept to at least four decimal places
y= -0.2868x+6.7098
I've noticed that the more I floss my teeth, the more cavities I tend to have when I go to the dentist. What type of correlation is this?
Positive
Dora has a company that produces backpacks for exploring. The probability that a
backpack is considered defective is 3%. When backpacks are randomly selected from the
production line, use the notation defective (D) and non-defective (N). If five backpacks are randomly selected, what is the probability that the first one
is defective and the next four are not?
P(DNNNN) = (.03)(.97)(.97)(.97)(.97) = 0.026