Equations
Vocabulary
Probability
Data
Graphs
100
How to find z?
100
what is the core meaning of a Null Hypothesis and Alternative Hypothesis?
Null Hypothesis (Hâ‚€)No change, no effect, no difference.
Alternative Hypothesis (Ha) a change, an effect, or difference.
100
What is the probability of flipping a fair coin and getting Tails?
0.5 (or 1/2 50%)
100
Finding the Mean
Question: What is the mean of the dataset: 3, 7, 8, 5, 12?
Add the numbers together (3 + 7 + 8 + 5 + 12 = 35). Divide the sum by the total number of data points(35/5 = 7)
100
What type of graph uses bars to show the frequency of data grouped into intervals?
Histograms
200
what is the binomial probability formula?
P(X = K) = (n/k) p^k(1-p)^n-k
200
What does the word sample mean?(Give an example!)
A smaller, representative subset of the population that is actually measured or observed to collect data (example, 1,000 randomly selected voters). [1]
200
If the probability that it will rain tomorrow is 0.3, what is the probability that it will not rain tomorrow?
0.7 (or 70%)
Work: The sum of all possible outcomes must equal 1.
1-0.3=0.7 or 70%
200
Finding the Median
Question: What is the median of the dataset: 14, 3, 9, 21, 7, 2?
First, arrange the numbers in order from smallest to largest: 2, 3, 7, 9, 14, 21. Because there is an even number of data points (6 points), take the average of the two middle numbers, 7 and 9 then divide by 2 = 8)
200
In a box and whisker plot, what percentile does the lien inside the box represent?
The median
300
What is the chi-square test statistic formula?
X^2 =(O - E)^2 / E
300
What does the word variable mean in Statistics?( give an example too!)
Variable: Any characteristic, number, or quantity that can be measured, counted, or categorized (an example is age, income, or hair color).
300
You roll a single fair six-sided die. What is the probability of rolling an even number?
1/2 (or 0.5 / 50%)
Work: Total outcomes:6 Even outcomes: 3
Probability: 3/6=1/2.
300
Finding the Range
Question: What is the range of the dataset: 45, 12, 89, 34, 76, 23?
Subtract the minimum value from the maximum value. The maximum is 89 and the minimum is 12 (89 - 12) = 77
300
If a distribution has a long tail pointing to the right, is it skewed right or left?
Right
400
What is the sample variation equation?
S^2=mew(xi - mean) ^2/ N
400
What does the word parameter mean?
A fixed numerical value that describes an entire population (example the true average height of all adult women).
400
A bag contains 3 red marbles and 7 blue marbles. If you pick one marble at random, what is the probability it is red?
0.3 (or 3/10 /30%)
Work: Total marbles: 10 Red marbles: 3
Probability: 3/10 =0.3
400
A bag contains 4 red marbles, 3 blue marbles, and 5 green marbles. What is the probability of randomly picking a blue marble?
First, find the total number of marbles (4 + 3 + 5 = 12). Put the number of favorable outcomes over the total outcomes 3/12, which simplifies to 1/4 or 0.25.
400
What kind of plot is best used to show the relationship or correlation between two continuous variable?
A scatter plot
500
What is the margin of error equation when using population standard deviation?
E=t^*(s/ square root (n))
500
What does the word variance mean or measures?
A measure of how spread out the data points are from their calculated mean value.
500
You flip a fair coin twice. What is the probability of getting heads on both flips?
1/4 (or 0.25 / 25%)
Work: Probability of Heads on flip 1 and 2 = 1/2
Multiply independent events: 1/2 X 1/2 = 1/4
500
Identifying the Mode
Question: What is the mode of the dataset: 5, 12, 5, 8, 12, 3, 12, 9?
Count how often each number appears. The number 5 appears twice, and the number 12 appears three times. Because 12 appears the most frequently, it is the mode.
500
What type of statistical graph plots the residuals on the vertical axis and the independent variable on the horizontal axis to determine if a linear model is appropriat?
A residual plot