Inference
What are the conditions that have to be satisfied before calculating the test statistic
3. Ms. Fey is a manager at a restaurant. To improve the dining experience for her customers, she
uses a digital music service to create a playlist of songs that will be played in the restaurant.
The playlist contains 1,000 songs and consists of four different types of music in the following
quantities: 200 country songs, 400 pop songs, 100 rock songs, and 300 jazz songs. The digital
music service will select songs at random from the playlist to be played in the restaurant. Any
song can be replayed at any time.
Hint: It has nothing to do with chi-squared
Essentially correct (E) if the response satisfies
the following four components are mentioned in context:
what distribution has an area of one?
Essentially correct (E) if the response satisfies the
following one component: student says "WHAT IS ALL DISTRIBTIONS!!!"
Partially correct (P) if the response satisfies the
following four components: student says "all"
What is the difference between capital X and lowercase x (in stats)
Essentially correct (E) if the response satisfies the
following three components: Identifies capital X as representing a random EX:(X=possible dice rolls 1,2,3,4,5,6)
Identifies lowercase x as representing a random variables value EX:(x=4 out of possible dice rolls 1,2,3,4,5,6)
contrast capital X and x
What is the probability of rolling a 4?
Essentially correct (E) if the response satisfies the
following components: student says 1/6 or .16667
Which is better statistics or pre-calculus?
TRICK QUESTION NETHIER!!!!!
A school principal believes that more than 60% of students support a new lunch policy.
A random sample of 100 students is taken, and 68 students say they support the policy.
State the null and alternative hypotheses.
Essentially correct (E) if the response satisfies the
following components:
What is the most common distribution in life?
Essentially correct (E) if the response satisfies the
following components: student says "normal distribution"
What symbol is used for a sample proportion
Essentially correct (E) if the response satisfies the
following components: student says "P hat"
What is the probability of getting exactly 2 heads? when said coin is filped 3 times
Essentially correct (E) if the response satisfies the
following components: students answear contains 3/8 or .375
Why should conclusions be stated in context?
Essentially correct (E) if the response satisfies the
following components: student says "Its guaranteed points on the AP test"
The heights of adult trees in a large forest are normally distributed with a mean of 40 feet and a standard deviation of 8 feet.
A forestry researcher randomly selects 25 trees and records their average height.
(c) What is the probability that the sample mean height is between 38 and 42 feet?
Essentially correct (E) if the response satisfies the
following components
if student gets 0.7888 by either useing the calc or by useing the Z-score table
The following data represent the number of minutes 24 students spent studying for a statistics exam:
8, 12, 15, 18, 20, 22, 24, 25, 27, 28, 30, 32, 35, 38, 40, 42, 45, 48, 50, 55, 60, 65, 72, 90
create a box and whisker plot from the data
hint: use stats and then edit
Essentially correct (E) if the response satisfies the
following components:
Minimum non-outlier = 8
Q1 = 23
Median = 33.5
Q3 = 49
Maximum non-outlier = 72
bonus point if student creates the box and whisker plot diagram
what is significance level typically?
Essentially correct (E) if the response satisfies the
following components: Student says "its typically .05"
A bag contains 5 red marbles and 3 blue marbles. One marble is selected at random and not replaced. A second marble is then selected.
What is the probability that both marbles are red?
Essentially correct (E) if the response satisfies the
following components: students answear is 5/14
A population has standard deviation 12 and sample size 36. Find the standard error.
Essentially correct (E) if the response satisfies the
following components: student says "The standard error is 2"
What are 3 conditions that must be meet for data from a survey to not be bais
Essentially correct (E) if the response satisfies the
following components: student has three of the 6 aspects
What is the empirical rule or what is the percentage for 1 standerd deviation 2 standerd deviation and 3 standerd deviations?
Essentially correct (E) if the response satisfies the
following components:
1 standerd deviation=68% or 34%
2 standerd deviation=95% or 13.5%
3 standerd deviations=99.7% or 3.5%
(note: that if student filp flops between the percentages on the left and right they are wrong)
or
student says "it is a rough estimate for the area under a bell graph for each standerd deviation"
What is Z-score and how do you find it?
Essentially correct (E) if the response satisfies the
following components:
Z= (x- mean)/ standerd deviation
student says "its how many standard deviations a value is above or below the mean"
A card is drawn from a standard 52-card deck.
What is the probability that the card is a king or a heart?
Essentially correct (E) if the response satisfies the
following components: students answear is 4/13 or .3077
A fair coin is flipped 5 times. What is the probability of exactly 3 heads?
Essentially correct (E) if the response satisfies the following components:
student gets 0.3125 or 31.25% by useing either binompdf or binomial distribution formula
What test would be used to find if one of the brands are more popular than what is stated?
The top four General Mills cereal brands are Honey Nut Cheerios, Lucky Charms, Trix, and Cookie Crisp.
When given those four options, the researchers want to see if any of those four brands are more popular than the others. A random sample of 100 people who purchased one of the four cereals was taken. Here are the results.
Brands: Cheerios Lucky Charms Trix Cookie Crisp
Frequency: (Cheerios,33) (Lucky Charms,26) (Trix,24) (Cookie Crisp,17)
Essentially correct (E) if the response satisfies the
following component: student says "what is chi-squared"
This will not be on the test
A researcher records the test scores of 200 students and creates a histogram. The distribution is skewed right with a mean of 78 and a median of 72. There are several unusually high scores near 100. If the highest 10 scores are removed from the data set, predict what will happen to the mean, median, and standard deviation. Explain why.
Essentially correct (E) if the response satisfies the
following components: students answear contains the following The mean will decrease, the median will stay about the same, and the standard deviation will decrease. All within context
using the type 1 and type 2 error table Fill in the data for each box of the table when confidence level=95% and power=80%
Essentially correct (E) if the response satisfies the
following components:
type 1 error chance is .05 or 5%
type 2 error chance is .8 or 80%
the box where we reject the null and the null being false chance is .2 or 20%
the box where the null is true and we FAIL TO REJECT the null chance is 95% or .95
BONUS POINTS: if student use's significance level symbol and beta
A company finds that 30% of customers buy Product A, 40% buy Product B, and 15% buy both products.
What is the probability that a randomly selected customer buys neither Product A nor Product B?
Essentially correct (E) if the response satisfies the
following components: students answear is 45%
FREE SPACE!!!!!!
give the student who picked this space 500 points and no one else