Vocab
The difference between the highest and lowest values in a data set.
What is range
Conclusion for a Significance Test
What is since the p-value (less than/greater than) significance level, (we reject/fail to reject H0). We do/do not have convincing evidence for Ha (context)
An error in data collection or sampling that results in an unrepresentative sample or skewed results
What is bias?
A bag contains 5 red marbles and 3 blue marbles. The probability of randomly selecting a blue marble is this
What is 3/8
The value that measures how many standard deviations a statistic is from the mean is called this.
What is a z-score
The value that appears most frequently in a dataset.
What is mode
Slope
What is with each additional x-variable, the predicted y-variable increases/decreases by slope.
A distribution where mean is greater than median.
What is skewed right
The probability that an event will not happen
What is the complement
If a p-value is smaller than the significance level, we do this to the null hypothesis.
What is reject the null hypothesis
The sum of all frequencies up to a specific point or interval
What is cumulative frequency
Expected value
What is if many, many (context), the average number of (X-context) is about (expected value).
Sampling method utilized when dividing subjects into groups before randomly assigning treatments to reduce variability.
When finding the probability of either event A or event B happening, you use this rule:
P(A or B)=P(A)+P(B)−P(A and B)
What is the Addition Rule
A confidence interval gives a range of values that is likely to contain this.
What is the true population parameter
A measurement of the average squared distance that data points fall from the mean
What is variance
r2
What is about r2% of the variation in y-variable can be explained by the LSRL with x-variable.
The purpose of random sampling
What is generalizability
Probabilities stay constant and each event remains independent when this occurs
What is (with) replacement
What is to ensure that observations in a sample are close to independent when sampling without replacement.
A statistical guideline that states for a normal distribution, most of the data falls within three standard deviations of the mean
What is the empirical Rule (68-95-99.7 rule)
Power
What is if Ha (context) is true at a specific value the probability of finding convincing evidence to reject H0 is power.
The difference between nonresponse bias and response bias
Nonresponse Bias: Missing data because the chosen sample refuses or is unable to participate.
Response Bias: Skewed data because participants answer inaccurately, dishonestly, or in a biased manner.
The difference between mutually exclusive and independent events
Mutually : Events cannot overlap/occur at once
Independent: Events can overlap, but they don't influence each other.
The difference between a matched pairs inference and two sample t inference
Matched pairs t-inference evaluates the mean of differences within the same subjects or natural pairs (like twins). Two-sample t-inference compares the means of two entirely independent groups.