Refer to the following contingency table comparing 2 teachers
and the number of students receiving grades...
Refer to the following contingency table comparing 2 teachers
and the number of students receiving grades in the 70's, 80's, or
90's.
70's
80's
90's
teacher
A
75
46 27
teacher
B
52
63 39
A. What is the observed value for students scoring 80's
in teacher B's class?
B. What is the expected value for students scoring 70's
in teacher A's class?
C. What is the (O-E)2/E value for students
scoring in the 90's in teacher A's class?
D. What...
A random sample of 36 seventh grade students in Harvard are
given a test on a...
A random sample of 36 seventh grade students in Harvard are
given a test on a reading test. Below are their raw scores.
73, 77, 80, 80, 84, 86, 91, 93, 93, 93, 94, 97, 100, 100, 103,
103, 104, 105, 105, 106, 108, 110, 111, 117. 120, 120, 123, 124,
126, 128, 129, 129, 130, 130, 136
Sample mean = 105.97
Sample standard deviation = 17.18
Nationally 30% of the students score 110 points or higher on
this test....
Are there more children diagnosed with Autism Spectrum Disorder
(ASD) in states that have larger urban...
Are there more children diagnosed with Autism Spectrum Disorder
(ASD) in states that have larger urban areas over states that are
mostly rural? In the state of Pennsylvania, a fairly urban state,
there are 245 eight year olds diagnosed with ASD out of 18,440
eight year olds evaluated. In the state of Utah, a fairly rural
state, there are 45 eight year olds diagnosed with ASD out of 2,123
eight year olds evaluated ("Autism and developmental," 2008). Is
there enough...
A craft brewer sells beer in 2 nearby towns. Some months, he
sells more in Town...
A craft brewer sells beer in 2 nearby towns. Some months, he
sells more in Town 1 & other months hesells more in Town 2.
However, he is pretty sure that he usually sells more in Town 1.
So, he has set up the following hypothesis test. He has also looked
up the sales figures from the last 30 months in both towns and
calculated some sample statistics. Those are below too. Use this
information to answer/do the following.
H0...
A study considers how the college entrace exam scores
for students in 2018
compared to that...
A study considers how the college entrace exam scores
for students in 2018
compared to that of the students in 1988. The national
mean score in 1988 in 500 (out of
1000 possible points). Based on a simple random sample
of 10,000 students, the 2018
sample mean socre is 497 (out of 1000 possible points),
and the standard deviation s=100.
1.1 State the null and the alternative hypotheses, and
explain your reasoning for choosing an one-sided or a two-sided
test....
A researcher is testing the effectiveness of a new herbal
supplement that claims to improve memory...
A researcher is testing the effectiveness of a new herbal
supplement that claims to improve memory performance. A
sample of n = 25 college students is obtained and each student
takes the supplement daily for six week. At the end of
the 6-week period, each student is given a standardized memory test
and the average score for the sample is M = 39. For the
general population of college students, the distribution of test
scores is normal with a mean of µ =...