Data Types and Miscellaneous
(1.2)
(1.2)
Nominal Data
What is the type of categorical data which has no distinct or defined order?
Simple Random Sample
What is the kind of sample where each member of the population has an exactly equal chance of being selected?
Explain how to find the IQR given a list of values.
Put in order, find Q1 and Q3, then subtract Q3-Q1.
How do you calculate z score?
Your value minus the mean, then divided by the standard deviation.
True or false, to get the mean of the sample, you divide by the square root of the sample size.
False, the mean stays the same. (Standard error = SD/sqrt(n)
Data
What do you call the type of information in a known context to be studied?
Stratified Sampling
What do you call the type of sampling where a population is divided into smaller groups or strata and then samples are randomly selected from each group.
Using your notes, explain the processes of calculating the standard deviation.
Find the mean, subtract the mean from each value, square each, add, divide by n-1, square root.
How do you calculate the p value once you have your z score?
You use the z chart to look up the p value, matching the decimals of the z score.
True or false: A larger sample size leads to a smaller standard error.
True.
Boxplots
What happens when the sample we choose does not reflect the full spectrum of the population?
Five Number summary
What do you call the list that contains minimum, Q1, Median, Q3 and Maximum of a variable?
The empirical rule says that roughly 68% of the data should be how close to the mean?
Within one standard deviation (higher or lower).
True or false: if the population data is skewed right, then the means of several samples of the same size (e.g. 40) will actually tend to be normal.
True. This is known as the Central Limit Theorem.
Raw data
Data in original form. It has not been organized to be studied.
We want to survey a sample of seniors to determine which prom themes are desired this year. Explain the parameter of interest and the sampling statistic in this scenario.
Parameter of interest = choices of all seniors, sampling statistic = choices of only those seniors surveyed.
fivenum
Or,
What function gives you the five numbers summary?
You take the probability of one of the z-score and subtract the probability of the other z-score.
How do you find the probability between two z-scores?
If you are given the standard error and sample size, how can you find the original standard deviation?
Multiply standard error by the square root of the sample size.
Bar Graph
What is the type of chart you use to display categorical data counts or percentages?
Explain the difference between voluntary response bias and nonresponse bias
In nonresponse bias, we care that some have not replied, we depend on seeking them out again!
Interquartile Range (IQR)
What do you call the distance between Q1 and Q3?
You take 1 to subtract the value you find under the given z-score
How do you find the left side of the probability with a given z-score?
If you are given the standard error and the standard deviation, how do you find the sample size?
Divide the standard deviation by the standard error, then square it.