Question
In: Statistics and Probability
Some researchers claim that herbal supplements improve human memory. To test this claim, a researcher selects...
Some researchers claim that herbal supplements improve human memory. To test this claim, a researcher selects a sample of n = 25 college students. Each student is given herbal supplements daily for 6 weeks and then all the participants are given a standardized memory test. For the population, scores on the tests are normally distributed with µ = 70 and σ= 20. The sample of n = 25 students had a mean score of M = 80. Can we conclude that the memory scores of the sample after the “herbal supplement” treatment are significantly greater than those of the general population(population mean before treatment)? Perform a hypothesis test using a z- score statistic. Use a one-tailed test with α = .05.
The z-score statistic is
Solutions
Expert Solution
The z scare statistics is 2.50
Dear student,
I am waiting for your feedback. I have given my 100% to solve your
queries. If you satisfied with my answer then please please like
this.
Thank You
orchestra answered 2 years agoRelated Solutions
Some researchers claim that herbal supplements such as ginseng or ginkgo biloba enhance human memory. To test...
Some researchers claim that herbal supplements such as ginseng
or ginkgo biloba enhance human memory. To test this
claim, a researcher selects a sample of n = 25 college
students. Each student is given a ginkgo biloba
supplement daily for six weeks and then all the participants are
given a standardized memory test. Scores on the test are
normally distributed with μ = 70 and σ = 15. The sample
of n = 25 students had a mean score of M = 75. Is this...
Some researchers claim that herbal supplements such as ginseng or ginkgo biloba enhance human memory. To...
Some researchers claim that herbal supplements such as ginseng
or ginkgo biloba enhance human memory. To test this claim, a
researcher selects a sample of n = 36 college students. Each
student is given a ginkgo biloba supplement daily for six weeks,
and then all the participants are given a standardized memory task.
For the population, scores on the test are normally distributed
with µ = 70. The sample of n = 36 students had a mean score of M...
Some researchers claim that herbal supplements such as ginseng or ginkgo biloba enhance human memory. To...
Some researchers claim that herbal supplements such as ginseng
or ginkgo biloba enhance human memory. To test this claim, a
researcher selects a sample of n = 28 college students. Each
student is given a ginkgo biloba supplement daily for 6 weeks and
then all of the participants are given a standardized memory test.
Scores on the standardized test are μ = 80 and standard
deviation of 15. The sample of 28 students had a mean score of M =...
A researcher studies the effect of the herbal stimulant Buttercup on short-term memory; she randomly divides...
A researcher studies the effect of the herbal stimulant
Buttercup on short-term memory; she randomly divides a sample of 32
into four (4) groups. Each group receives 0 mg, 500 mg,
1000 mg and 1500 mg respectively and is then tested on their short
term memory span. She finds:
NUMBER
OF ITEMS REMEMBERED (MEMORY SPAN)
0.0
mg 500
mg 1000
mg 1500
mg
8 7 10 4
9 6 15 5
7 9 14 2
7 8 14 4
8 8 17 3
10 6 13 8
6 12 9 7
7 9 12 9
A. State the
Independent Variable and the Dependent Variable.
B. State the null
hypothesis in words...
A researcher wishes to test claim that there is no difference in the life span of...
A researcher wishes to test claim that there is no difference in
the life span of two types of reptiles: the Nile crocodile and
giant sea turtle. Sample data including the average lifespan of
both reptiles are provided below. Test the claim using α=0.05.
Nile Crocodile
Giant Sea Turtle
X ¯ 1 = 45
s 1 ==2.6
n 1 =12
X ¯ 2 =44
s 2 =6.5
n 2 =10
State the claim:
H 0 μ 1 claim
H 1 μ...
2. A researcher wishes to test the claim that there is a difference in the distribution...
2. A researcher wishes to test the claim that there is a
difference in the distribution of ages of elementary school, high
school, and community college teachers. Teachers are randomly
selected from each group. Their ages are recorded below. Can you
conclude that the distributions of teachers' ages at these
different levels of education are different? Use the Kruskal-Wallis
test. Use α = 0.05. Elementary 28,33,32,57,42,30 High school
41,46,43,52,47,36 Comm. College 44,50,41,66,50,40 need work
shown
A researcher developed a training program designed to improve memory retention. She applied this program to...
A researcher developed a training program designed to improve
memory retention. She applied this program to a population of
learning-disabled (LD) children in 2nd grade, where each
child received a moderately-intense (MI) and an intense (I) version
of the training program for 6 weeks. Afterwards, they were tested
with a standardized memory assessment. If she randomly selected
Child #5 to compare, which program version produced a better memory
score?
Intense
Moderately Intense
Child #
Score
Child #
Score
1
1...
A researcher wishes to test claim that that the average cost of a coke in Mexico...
A researcher wishes to test claim that that the average cost of
a coke in Mexico is different than the average cost for a coke in
Russia. The cost is measured in US Dollars. Sample data are
provided below. Test the claim using α=0.10.
Mexico
Russia
X ¯ 1 =1.26
s 1 =0.11
n 1 =14
X ¯ 2 =1.52
s 2 =0.09
n 2 =14
State the claim:
H 0 μ 1
H 1 μ 1≠ μ 2 claim...
A tree researcher wishes to test the claim made by a colleague that trees of a...
A tree researcher wishes to test the claim made by a colleague
that trees of a certain species in a forest to the north are the
same height as the same species in a forest to the south. The
researcher collected samples from both forests. In the northern
forest, the sample size was 9 trees, the sample average was 32.7
ft, and the sample standard deviation was 6.9 ft. In the southern
forest, the sample size was 12 trees, the...
To test whether memory changes with age, a researcher conducts an experiment in which there are...
To test whether memory changes with age, a researcher conducts
an experiment in which there are four groups of six subjects each.
The four groups are listed below. All subjects are in good health
and matched in other important variables such as years of
education, IQ, gender and motivation. Each subject is shown a
series of nonsense syllables (a meaningless combination of three
letters such as DAF or FUM) at a rate of one syllable every 4
seconds. The series...
ADVERTISEMENT
ADVERTISEMENT
Latest Questions
- 1. Explain why times of economic distress caused classical liberalism to fall out of favor.
- To demonstrate the practical implementation of the public\private encryption, you have been asked to compete the...
- Suppose we are thinking about replacing an old computer with a new one. The old one...
- The project has a critical path that is 4 months long. We are now part way...
- Consider the following hypothetical microprocessor. Assume this processor uses 32-bit instructions. Assume the 32 bits are...
- C Programing How would i edit this code to have it return the cipher text. void...
- What are some ways that a company could fail at trying to become a glocalized business?
ADVERTISEMENT