Back to basics
Linear regression
Probability
Normal distributions
Reject the HO!
100

What is an example of a categorical variable?

Ex: Anything qualitative such as gender, race, grade, zip code, etc. 

100

What is deliberate bias? 

When a question is worded to support a certain cause or illicit a particular response

100

A probability teacher is rolling a die. Y is the number that comes up. Is the random variable Y discrete or continuous?

Discrete 

100

The null hypothesis is symbolized using...

Ho

100

The P-value for a hypothesis test is P = 0.066. Do you reject or fail to reject Ho when the level of significance is α = 0.05?

Fail to Reject Ho, since the P value is greater than the level of significance

200

What is an example of a discrete quantitative variable?

Ex: number of children, number of pets, items of clothes (NO decimals, only whole number possibilities) 

200

Which r-value represents a weaker correlation? r= -0.9 or r=0.2

r=0.2

200

What is it called when two events cannot occur simultaneously?

Mutually exclusive

200

True or False: When the distribution is not normal (such as skewed), the shape of the sampling distribution will still become approximately normal if the sample size is “large”.

True 

200

True or false: In a two-tailed hypothesis test, the alternative hypothesis states that the parameter is greater than or less than a specific value.

False!

300

What are the measures of position? (hint:5 # summary)

1.Minimum
2.1st Quartile (Q1)
3.Median (aka 2nd Quartile)
4.3rd Quartile (Q3)
5.Maximum

300

What is the main difference between observational and experimental studies? 

Observational: Not applying a treatment, can't establish causation
Experimental: applying a treatment/placebo, can establish causal relationships

300

Is the following a probability distribution? The random variable x represents the number of tickets a police officer writes out each shift.

Yes, the probabilities total 1 & are between 0 and 1.

300

As confidence level increases the width of interval ____.

Increases 

300

We want to test whether the mean height of eighth graders is 66 inches, as we suspect it's actually lower. State the null and alternative hypotheses.

Ho: μ = 66; Ha: μ< 66

400

What method of sampling?: A news station posts a poll on Instagram asking for the public's opinion on a new parking lot being built in town and people can choose to respond. 

Voluntary/Self-select

400

Given the following linear regression line, ŷ = -12 + 3.2x, what is the predicted value of y if x=2.4

-4.32

400

What percent of students with cell phones also have a driver's license?

74.3%

400

Calculate Claire's Z-score: It takes Claire 17 minutes to walk to class. Among all students, the average time it takes to get to class is 15 minutes with a standard deviation of 2 minutes. 

Z-score= 1

400

Describe a Type 1 and 2 error for this scenario:

Ho: Devyn does not have the flu

Ha: Devyn does have the flu


Type 1 (False positive): When Devyn does not have the flu but you say she does. 

Type 2 (False negative): When Devyn actually has the flu but you say she does not. 

500

Use the IQR method for identifying outliers to determine any in this data set: 0, 2, 5, 8, 9, 9, 10, 11, 12, 12, 14, 15, 20, 25

25 is the only outlier

500


1. No relationship

2. Nonlinear relationship 

3. Positive linear relationship 

4. Positive linear relationship 

5. No relationship 

6. Negative linear relationship. 


500

Define sample space, outcome, and event. 

Sample Space: ALL possible outcomes of a probability experiment

Outcome: result of a single trial of a probability experiment.

Event (E): a specific set of outcomes of a probability experiment.

500

According to the Empirical rule, what percent of data is in the blue-shaded area?

68%

500

A new educational app is designed to improve students' math skills. A teacher decides to evaluate its effectiveness by conducting a study with her class of 25 students.

  1. Phase 1: Students take a math test before using the app to establish a baseline score.
  2. Phase 2: Students use the app for 4 weeks and then take the same math test again.

The teacher wants to know if there is a significant improvement in the student's math scores after using the app.

Two-sample paired test, one-sided