But I Regress...
Room of Requirement(s)
I've got 99 Probabilities and Significant Ain't One
What's With All the Hyp(e)
I'm Quite Confident
The Column Without A Cool Name
100
All linear correlation coefficients are between these two values.
Between -1 and 1.
100
A friend did a one sample z-test on the following data. Why is she wrong?
A random sample of 22 fifth grade pupils have a grade point average of 3.5 in math with a standard deviation of 0.452. The grade point average (GPA) of all fifth grade pupils of the last five years is 3.2. Is the GPA of the 22 pupils different from the populations’ GPA?
A z-test requires that we know the population standard deviation.
100
What is the probability that a z score will be greater than -1.31?
.9049
100
In a test with
alpha=0.05
and p-value 0.049, you would conclude this.
Reject H0
100
The critical value used in creating a 95% confidence interval for mu when you have 12 data points and there is no sigma.
t_c = 2.201
100
A list of at 4 Greek letters used in stats class, along with what they represent.
To Sum: Sigma
Population standard deviation: sigma
Significance level (or Population regression y-int): alpha
Pop. Mean: mu
Pop. Linear correlation: rho
Population Regression Slope: beta
A distribution for variance: chi
Degrees of freedom: nu
200
The ranks of the following data:
8.1, 5.2, 6.3, 4.5, 7.2, 6.3
6, 2, 3.5 , 1, 5, 3.5
200
The requirement to use a t-test if the data might have a slight skew.
n should be greater or equal to 30
200
The z-score that corresponds to the top 10% of all scores.
z=1.28
200
The test statistic for a sign test that there were an equal number of "Yes" and "No" responses from a survey of 20 students for which 10 answered "Yes", 8 answered "No", and 2 did not respond.
x=8
200
If you have 40 data points with a Range of 21, this is the width for the classes of a frequency table with 5 classes.
5
(21/5 =4.2...)
300
If you have 10 pairs of data, and you're testing for a correlation with a 0.05 significance level using the rank correlation test, this is the critical value.
r_c =0.649
300
___A____ is used for testing data in a contingency/2-way table, ____B____ if a distribution of data fits the expected, and ___C___ is for when you want to test what a t-test does but have too many samples.
A: Test for Independence/Homogeneity
B: GOF-test
C: ANOVA
300
What is the full calculator command (with parameters) for finding the probability of more than 6 successes in a binomial experiment with 10 trails when p=0.2
1-binomcdf(10, 0.2, 6)
300
The Null and Alternative Hypotheses for the experiment:
Since 2006 at the Tennis US Open, men have challenged 1412 referee calls and had 421 overturned, and women have challenged 759 and had 220 overturned. We want to test the claim that men have better success challenging calls than women.
H0 : p1 = p2
H1 : p1 > p2
300
What happens to a confidence interval when n gets larger.
The confidence interval gets smaller.
because the margin of error is smaller
the confidence interval gets more precise.
300
The 35th percentile of following data set:
0, 1, 1, 1, 2, 3, 3, 4, 4, 4, 4, 5, 6, 6, 7
3
400
The r-value and conclusion for the test for linear correlation on the data:
x: 1 | 3 | 5
y: 7 | 10 | 9
r=0.fix
No significant linear correlation.
400
The requirement/s for a discrete probability distribution to be considered legitimate.
The probabilities must add to 1,
and
The probabilities each must be between 0 and 1.
400
P(1st Class and Survived)
and P(Survived | 1st Class)
0.1526 and 0.6204
400
The p-value for a test statistic that has a value of 3.1 when n=5, and your alternate hypothesis looks like
H_1: mu != 12
and there is no sigma.
p-val:0.0362
400
The interpretation for the 90% confidence interval for statistics class's test scores that had a mean of 81, and a margin of error for the mean of +/- 4.
We are 90% confident that the interval from 77 points to 85 points is one that contains the population mean score of the test.
400
The sampling method if you go to a library and select 15 books from each of the sections Mystery, Science Fiction/ Fantasy, Romance, and General Fiction, and count the number of pages in each book.
Stratified Sampling
500
An r2 value of .87 tells you this.
That only 87% of the variation in y is explained by its linear relationship with x.
500
When you want to compare the means of two different samples and no population standard deviations are known, these are the three different tests that could be used, with reasons why we'd used each.
Sign-test for dependent samples, no parameters assumed
t-test for Dependent samples, if normal distribution
2-sample t-test for independent samples when normal dist is assumed
500
The probability that 25 runners have a mean resting heart rate of less than 53 bpm, Assuming all runners have a mean resting heart rate of 57 beats per minute with a standard deviation of 7 bpm.
0.0021
500
If a p-value is 0.013 for a test statistic of t=2.5, that means that 0.013 is the probability that t will be ________________ than 2.5 , assuming ____________.
The p- value is the probability that the t will be as extreme or more extreme than 2.5, assuming H0 is true.
500
All confidence intervals for either estimates of means or proportions are essentially just
_____ ± ______
point estimate ± margin of error.
{Or Point Estimate ± Critical Value*Standard error}
500
Four golfers are about to begin a round of golf and toss a tee to randomly decide starting order. What is the probability they tee off in alphabetical order?
0.04166... or 1/24