A student experiment investigating the potential impact of, Ask an Expert

Statistics

A student experiment investigating the potential impact of caffeine on studying for a test involved 30 subjects randomly divided into two groups. Each group took a memory test. The subjects then each drank two cups of regular (caffeinated) cola or caffeine-free cola. Thirty minutes later they each took another version of the memory test, and the changes in their scores were noted. Among the 15 subjects who drank caffeine, scores fell an average of points, with a standard deviation of 2.988 points. Among the no-caffeine group, scores went up an average of 1.429 points, with a standard deviation of 2.441 points. Assumptions of Normality were deemed reasonable based on histograms of differences in scores.

a) Did scores change significantly for the group that drank caffeine? Test an appropriate hypothesis and state your conclusion.

b) Did scores change significantly for the no-caffeine group? Test an appropriate hypothesis and state your conclusion.

c) Does this indicate that some mystery substance in noncaffeinated soda may aid memory? What other explanation is plausible?

View complete question

Statistics and Probability, Statistics

Category:- Statistics and Probability
Reference No.:- M92232199

Have any Question?Write your Review or question?

Related Questions in Statistics and Probability

Question suppose we wanted to conduct a survey it is

Question: Suppose we wanted to conduct a survey. It is desired that we produce an interval estimate of the population mean that is ±5 from the true population mean with 99% confidence. Based on a historical planning valu ...

Indigo environment corp just paid a dividend of 1 per share

Indigo Environment Corp. just paid a dividend of $1 per share. The dividends are expected to grow at 25% for the next eight years and then level off to 6% growth rate indefinitely. If the required return is 10%, what is ...

Arvo corporation is trying to choose between three

Arvo Corporation is trying to choose between three alternative investments. The three securities that the company is considering are as follows: Tax-free municipal bonds with a return of 8.8%. Wooli Corporation bonds wit ...

You have a bag with three fair dice one is 4-sided one is

You have a bag with three fair dice. One is 4-sided, one is 6-sided, and one is 12-sided. You reach into the bag, pick one die at random, and roll it. The outcome of the roll is 4. What is the probability that you rolled ...

On the production line the company finds that 956 of

On the production line the company finds that 95.6% of products are made correctly. You are responsible for quality control and take batches of 30 products from the line and test them. What number of the 30 being incorre ...

How does a histogram help us know the probability of

How does a histogram help us know the probability of getting a certain value for a variable? In other words how does the histogram relate to probability?

Plastic sheets made by a machine are periodically monitored

Plastic sheets made by a machine are periodically monitored for fluctuations in thickness. If the true standard deviation in thickness exceeds 2.0 millimeters, there is cause for concern about product quality. Past exper ...

The average starting salary for graduates at a university

The average starting salary for graduates at a university is $33,000 with a standard deviation of $2,000. If a histogram of the data shows that it takes on a mound shape, the empirical rule says that approximately 68% of ...

An independent-measures study has one sample with n 10 and

An independent-measures study has one sample with n = 10 and a second sample with n = 15 to compare two experimental treatments. What is the df value for the t statistic for this study?

Question 1a consumer analyst reports that the mean life of

Question 1 A consumer analyst reports that the mean life of a certain type of alkaline battery is no more than 63 months. Write the null and alternative hypotheses and note which is the claim. A)Ho: μ ≤ 63 (claim), Ha: μ ...

4,153,160 Questions Asked
13,132 Experts
2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Recent Questions

Ask Statistics and Probability Expert