Hypothesis Testing Basics and Error
Traditional Method
P-Value Method
Confidence Interval Method
Review Problems
100
In a null hypothesis, the sign of the statement is always________.
=
100
Steps 3 and 4 To the traditional method
3. Calculate critical values and draw the graph 4. Find the test value and label on picture
100
We Reject H0 if this is true.
P-value is less than alpha/ alpha is greater than P-value
100
This must be true in order to use the Confidence Interval Method
Two tailed test
100
This value has 50% of data above and below it.
Median/Q2
200
The area that comes from the Test Value is called
P-Value
200
Test value equation for Chi-Square
Chi-Square = df (s-squared) / Sigma-squared
200
The 3rd and 4th step to the P-Value method
3. Calculate test value/find p-value 4. compare P-value to alpha
200
This type of test can not be done in the calculator
Chi-Square
200
There are this many hearts in a standard deck of cards.
13
300
If you reject a null hypothesis that is true you have made this type of error.
Type I
300
Mr. Martin thinks that his cat meows more than 100 times a day on average. To test this, he takes a sample of 20 days and finds his cat meowed an average of 115 times with a standard deviation of 2. Test Mr. Martin's claim at alpha = 0.05..
Reject H0 Support Mr. Martin's claim T= 33.54
300
We are not doing the P-value for this type of test.
Chi-Square
300
Formula for a confidence interval for Chi-Square
df (s-squared) / Chi Square R and L
300
This distribution is symmetric but not bell-shaped
Uniform
400
The probability of making a type II error.
Beta
400
Mr. Martin thinks his friend has an 85% chance of being late to any given event. Mr. Martin takes a sample of 50 events and finds his friend is late 45 times. Test Mr. Martin's claim at alpha = .01.
FTR H0 Support claim that p = .85 Z = .99
400
Bonus: What is Mr. Martin's cat's name?
Luna
400
If this is in the interval, FTR H0
Parameter from the Null
400
Binomial probability formula
P(x) = nCx(p^x)(q^n-x)
500
A school superintendent must make a decision whether or not to cancel school because of a threatening snow storm. What would the results be of Type I and Type II errors for the null hypothesis: The weather remains dry
Type I: Weather remains dry, school is needlessly canceled Type II: School isn't canceled and the storm hits
500
What are the critical values for a two tailed Chi-Square test with alpha = .1 and n = 22
Chi-Square R = 32.671 Chi-Square L = 11.591
500
Mr. Martin thinks that the average time it takes him to grade a test is 6 minutes. To test this, he takes a sample of 40 tests and finds his average time is 7.6. It is known that Mr. Martin has a standard deviation of 1.5 minutes when it comes to grading. Test at alpha = 0.01
P= 1.5 x 10^-11
500
Mr. Martin thinks the standard deviation of the amount of water he drinks a day is 8 oz. A sample of 41 days had a standard deviation of 6.5 oz. Test his claim at alpha = 0.05.
5.3 < S.D. < 8.0 Reject H0 Reject Claim
500
Suppose you do five independence tests of the form Ho: u=38 versus Ha: u > 38, each at the a = 0.01 significance level. What is the probability of committing a Type I error and incorrectly rejecting a true null hypothesis with at least one of the five tests.
0.049
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