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July 25, 2014

Search: An odds ratio of 1.2 (95% confidence interval: 0.8-1.5) is found for the association of low socioeconomic status

Number of results: 8,470

stats
The following data were collected from a case-control study of breast cancer and fat intake: case control High-fat diet 10 5 Low-fat diet 40 55 50 60 Statistical inferences for odds ratios are based on the natural log of the odds ratio, rather than the odds ratio itself (...
July 16, 2013 by thane

RES 341
A sample of 300 is taken and the sample mean is computed to be 7.65 and the sample standard deviation is 5. Assume the data is ratio level. Compute the 95% confidence interval on the mean. Compute the 3.9% confidence interval on the mean Which confidence interval is more ...
October 16, 2010 by Meh

Statistics
Which of the following statements best describes the uncertainty associated with a 95% confidence interval for a population proportion, computed from a simple random sample? A. We don't know whether the particular confidence interval is successful or not, but 95% of ...
May 18, 2012 by Mary

statistics
Refer to Table 1 in the article Snail Shells in a Practical Application of Statistical Procedures in the Electronic Reserve Readings. Find the margin of error, E, with a confidence interval of your choosing (50-99%). What is the significance of choosing a confidence interval...
April 26, 2012 by len

Environmental Management
A. The 95% confidence interval is: (a) Larger than the 99% confidence interval (b) Smaller than the 99% confidence interval (c) The same as the 99% confidence interval
July 13, 2009 by Jox

Math-Stat Help
In a random sample of 78 teenagers, 32 admit to texting while driving. Construct a 98% confidence interval for the percentage of teenager that text while driving. Start by showing that conditions for constructing a confidence interval are met. 1) Check conditions 2) confidence...
April 11, 2013 by MELISSA

Statistics
In 1998 a San Diego Reproductive clinic reported 49 live births to 207 women under the age of 40 who had previously been unable to get pregnant. Using the 90% confidence interval calculated above, would it be misleading for the clinic to report a success rate of 25%? A) Yes, ...
October 27, 2013 by Jeffrey

Statistics
The standard deviation for a population is σ = 15.3. A sample of 36 observations selected from this population gave a mean equal to 74.8. a) Make a 90% confidence interval for μ b) Construct a 95% confidence interval for μ. c) Determine a 99% confidence interval...
November 21, 2013 by ----

BIOLOGY - LAB
What is Confidence Interval? Is it better to have a large Confidence Interval or a small Confidence Interval? Briefly explain.
March 24, 2009 by biology

Statistics
The 95% confidence interval is: (a) Larger than the 99% confidence interval (b) Smaller than the 99% confidence interval (c) The same as the 99% confidence interval
October 28, 2007 by Thano

Statistics
Multiple Choice Which of the following statements is true about the 95% confidence interval of the average of a sample? A) 95 of 100 avgs of samples will be within the limits of the confidence interval. B) There is a 95% chance the avg of the population to be within the limits...
July 26, 2013 by Andrew

Statistics
We have calculated a 95% confidence interval for a proportion and would prefer the confidence interval to be more precise, that is narrower. Using the same sample, we can narrow the confidence interval using which of the following? A) increasing the confidence level B) ...
October 27, 2013 by Nick

Statistics
1. A certain population follows a normal distribution, with mean m and standard deviation s = 2.5. You collect data and test the hypotheses H0: m = 1, Ha: m 1. You obtain a P-value of 0.022. Which of the following is true? Why? a. A 95% confidence interval for m will include ...
November 29, 2008 by Latoya

Math 11
I am really stuck at these 4 questions. Pls help: a) Two spheres of the same density have a ratio of 9 to 16 inches in surface area, If the small sphere weighs 15 kg what does the sphere weighs. Answer to the nearest 10th of KG. b) The ratio of the volume of two cubes is 216 ...
April 7, 2014 by MK

epidemiology
11. A study to assess the relationship between smoking and lung cancer found that the odds ratio is 4. Using your own words, interpret the odds ratio.
June 19, 2014 by chy

Statistics
A confidence interval for a population mean has a margin of error of 3.1. a)Determine the length of the confidence interval. b)If the sample mean is 56.7, obtain the confidence interval.
May 21, 2014 by Anonymous

Statistics
A random sample of 90 observations produced a mean that = 25.9 and a standard deviation s =2.4 (a)Find a 95% confidence interval for u (b)Find a 90% confidence interval for u (c)Find a 99% confidence interval for u (Use integers or decimals for any number in the expression. ...
March 23, 2014 by Carol Harper

Math
What effect will an outlier have on a confidence interval that is based on a small sample size? A) The interval will be smaller than an interval without the outlier. B) The interval will be the same with or without the outlier. C) The confidence interval will be wider than an ...
November 28, 2009 by Jennifer

statistics
What do confidence intervals represent? What is the most controllable method of increasing the precision of or narrowing the confidence interval? What percentage of times will the mean, or population proportion, not be found within the confidence interval?
April 30, 2010 by Amy

Statistics
. As the sample size increases The confidence interval also increases (gets larger) The confidence interval decreases (gets smaller) The confidence interval stays the same The population mean increases.
June 22, 2010 by Jacob

Elementary Statistics
1) Construct a confidence interval of the population proportion at the given level of confidence. x=60,n=300, 99% confidence. The 99% confidence interval is (_,_) 2) A researcher wishes to estimate the proportion of adults who have high-speed internet access. What size sample ...
June 6, 2012 by Erin

Statistics:Significance Test and Confidence Interv
Significance Test and Confidence Intervals In General: The article contains a 95% confidence interval. Would the margin of error in a 99% confidence interval computed from the same data be less, the same, or greater?
September 11, 2007 by Carma

Statistics
You are given the following information obtained from a random sample of 6 observations. Assume the population has a normal distribution. 13 14 17 14 17 15 a. What is the point estimate of ? b. Construct an 80% confidence interval for . c. Construct a 98% confidence interval...
November 12, 2013 by Katie

statistics
The Frayed Nerves Anxiety Scale (FNAS) is used to measure the anxiety level of people on a scale from 0 to 1000. Four students were randomly chosen and given the FNAS before their second exam. Their scores were 700, 653, 740, and 707. The standard deviation sigma of the test ...
October 17, 2011 by Anand

Statistics
Suppose x has a mound-shaped distribution with sigma = 9 . A random sample of size 36 has sample mean 20. Is it appropriate to use a normal distribution to compute a confidence interval for the population mean m? Explain. Find a 95% confidence interval for m. Explain the ...
April 27, 2013 by Steph

STATISTICS
A study examining the relationship between fetal X-ray exposure and a particular type of childhood blood cancer found the following odds ratio (and 95% confidence interval) for the association: 2.44 (0.95 to 6.33). This result would likely be considered: clinically significant...
August 7, 2013 by Susie

STATISTICS
A study examining the relationship between fetal X-ray exposure and a particular type of childhood blood cancer found the following odds ratio (and 95% confidence interval) for the association: 2.44 (0.95 to 6.33). This result would likely be considered: a. clinically ...
August 10, 2013 by smoothjive

statistics
Consider a 95% confidence interval for a population mean constructed from a random sample of 250 observations taken from a Normal population. Sigma is known to be 14. If we were to construct another 95% confidence interval, this time using 1,000 observations, how would the ...
February 20, 2011 by AMY

statistics
Consider a 95% confidence interval for a population mean constructed from a random sample of 250 observations taken from a Normal population. Sigma is known to be 14. If we were to construct another 95% confidence interval, this time using 1,000 observations, how would the ...
February 20, 2011 by AMY

Statistics
When consumers apply for credit, their credit is rated using the FICO score. A bank manager used a random sample of the credit scores of 18 customers and determined the following 95% confidence interval: (613.6, 708.0) If the sample used 45 customers rather than 18 customers, ...
November 6, 2013 by Katelyn

statistical applications
In the media, numerous surveys are often displayed reporting percentages or proportions. A margin of error is often reported in the survey and this is used to calculate confidence intervals. Why is it important to create/report confidence intervals (CI) rather than just ...
May 28, 2010 by cortez

math
Given the information: the sampled population is normally distributed, = 10.4, n = 60, and = 81.2. a. Find the 98% confidence interval for b. Interpret the confidence interval in Where do i begin
November 17, 2008 by ks

stats
Would a proportion of 60% be likely, given the calculated confidence interval? Yes/No Find Answer to: 80% confidence interval ________+/-___________
June 24, 2011 by Anonymous

statistics
Consider a 90% confidence interval for μ. Assume σ is not known. For which sample size n=10 or n=20, is the confidence interval longer?
October 31, 2011 by Morgan

UOP
5) In a 95% Confidence Interval, the true mean has what chance of falling between the Lower Limit and Upper Limits of the calculated confidence interval? A. .90 B. 95% C. .05 D. 5%
April 13, 2013 by Linda

Statistics
Which of the following statements correctly interprets a 95% confidence interval on a population mean? a. It is a single point estimate b. Used to quantify the certainty of the sample standard deviation c. A 99% confidence interval is narrower than the 95% confidence interval ...
September 15, 2010 by Beata Chmielewska

statistics
10. Using the results of a Newsweek poll conducted in March of 2009, a 90% confidence interval on the proportion of adult Americans who have a favorable opinion of Barack Obama is given by (0.699, 0.741). If everything else is the same, but the confidence level increases, ...
May 8, 2013 by ali awan

QNT351
use a 95% confidence interval to estimate the difference between the population means. Interpret the confidence interval. random sample 390 x1 5258 s1 152 x2 5220 s2 192
September 27, 2012 by Terri

statistics
P(proportion) is 0.05446, n is 863 and a 90% confidence interval is required. What is this confidence interval?
December 23, 2011 by blue

statistics
Help!!!!!! A confidence interval estimate for the population mean is given to be (39,90, 48.11) If the standard deviation is 11.473 and the sample size is 52 determine the maximum error of the estimate. determine the confidence level used for the given confidence interval
November 9, 2011 by amy

Statistics
Hoping to lure more shoppers downtown, a city builds a new parking garage in the central business district. The city hopes that the parking revenues will pay for the garage. During a recent two month period (44 days), the city statistician calculated the 95% confidence ...
November 10, 2013 by Katie

stat
7. A researcher selects a random sample. A 90% confidence interval for a population mean  A) is an interval with margin of error 90%. B) has the property that if we repeatedly selected our random sample in exactly the same way, each time constructing a different 90% ...
December 5, 2010 by Anonymous

Statistics
Use the sample data and confidence level to construct the confidence interval estimate of the population p....n=5200, x=4821, 99% confidence
May 1, 2013 by Tangee

Statistics
Should companies use the same confidence interval each time a confidence interval is determined or should the level change based on situations? If it changes based on situations, what type of situations might call for higher confidence levels?
April 6, 2012 by John

Math-Statistics
Find a confidence interval for assuming that each sample is from a normal population. a. P x = 14, = 4, n = 5, 90 percent confidence b. P x = 37, = 5, n = 15, 99 percent confidence c. P x = 121, = 15, n = 25, 95 percent confidence Need to show my work/formula ...
December 6, 2011 by Richard

Statistics
A survey of community banks asked about the loan to deposit ratio (LTDR) a banks total loans as a percent of its total deposits. The mean LTDR for the 110 banks in the sample is xbar = 76.7 and the standard deviation is s = 12.3. In the text a 95% confidence interval (using a ...
February 26, 2007 by Jason L

statistics
How large a sample would be needed to form a 90% confidence interval for the mean nicotine content of a brand of cigarettes if the nicotine content has a normal distribution with sigma equal to 8.5 mg and the width of the interval (the length of the confidence interval) equal ...
November 17, 2013 by Alex

Statistics
When estimating a population mean μ, where the population standard deviation σ is known, we can: a. choose a larger z value, construct a wider confidence interval, and achieve a lower confidence level b. choose a smaller z value, construct a narrower confidence ...
November 14, 2012 by Melanie

statistics
A sample of n = 9 has a mean of M = 72 with SS = 162. Use the sample to make a point estimate of and to construct the 90% confidence interval for . (Round all answers to two decimal places = ? ? ( ? ) The 90% confidence interval for : ( ? , ? )
November 4, 2011 by Anonymous

statistics
A sample of n = 9 has a mean of M = 72 with SS = 162. Use the sample to make a point estimate of and to construct the 90% confidence interval for U. (Round all answers to two decimal places.) U = ? ? ( ?) The 90% confidence interval for U: ( ? , ? )
November 4, 2011 by Anonymous

Statistics
Answer the question Yes or No. Sam computed a 90% confidence interval for from a specific random sample of size n. He claims that at the 90% confident level, his confidence interval does not contain . Is this claim correct? Answer a. No b. Yes
July 7, 2012 by Desperate

statistics
Pleas HeLp!!!!!!!!!! A random sample of the test scores of 100 applicants for college entry at a large junior college showed a mean score of 72.6. Determine a 99%, 95%, and 90% confidence interval for the m mean score of all applicants at the junior college. Assume the ...
September 17, 2011 by courntey

Math Statistics
5. Students in an introductory statistics class were asked to report the age of their mothers when they were born. Summary statistics include Sample size: 36 students Sample mean: 29.643 years Sample standard deviation: 4.564 years a. Calculate the standard error of this ...
July 29, 2013 by James

Statistics
Use the sample data and confidence level to construct the confidence interval estimate of the population proportion p. n=500, x=350, 90% confidence ?<p<? (Round to three decimal places as needed.)
April 30, 2013 by Rob

math
With a confidence level of .95 and a confident interval of 5 and a population of 20,000 what is the sample size? With a confidence level of .99 and a confident interval of 5 and a population of 20,000 what is the sample size? Finally, using the sample size for question 1 and 2...
October 15, 2007 by sam

Statistics 101
A researcher plans to use a random sample of n= 500 families to estimate teh mean monthly family incomefor a large population. a 99% confidence interval based on the sample would be _________ than 90% confidence interval.
February 25, 2014 by Deedy

Statistics
(25 pts, 5 pts each) The ounces of coffee that a machine dispenses in 5-ounce cups have normally distributed. Suppose a sample of size 6 was taken from this machine, as shown as follows: 5.05 5.03 5.10 5.02 4.98 5.00 (for all calculations, keep at least six decimal places) (1...
May 9, 2014 by Trell

math 127
In 2008 ACT,Inc reported that 74% of 1500 randomly selected college freshman rerurned to college the next year. Estimate the national freshman to sophomore retention rate. a) Verify below the two condition are met for constructing a confidence interval for the population ...
July 27, 2010 by marylou

stat
A companys CEO wanted to estimate the percentage of defective product per shipment. In a sample containing 500 products, he found 30 defective products. (a) Find a 98% confidence interval for the true proportion of defective product. Show your calculations and/or explain the ...
August 20, 2011 by me,me

Statistics
If someone gives you a sample mean and a standard deviation, you can find a confidence interval. But what if someone gives you the confidence interval instead and asks you to find the sample mean? How can you do that? Here's an example: a 95% confidence interval for a mean is ...
October 4, 2011 by Hope

Statistics
What is meant by the 95% confidence interval of the mean ? That 95% of my sample is OK to do more tests. That I am 95% confident that the confidence interval will contain the parameter being estimated. That 5% of my sample is not OK. That I am 95% sure that the population mean...
June 22, 2010 by Jacob

statistics
What is meant by the 95% confidence interval of the mean ? That 95% of my sample is OK to do more tests. That I am 95% confident that the confidence interval will contain the parameter being estimated. That 5% of my sample is not OK. That I am 95% sure that the population mean...
August 17, 2010 by Karen

statistics
A 90% confidence interval for a population mean based on 144 observations is computed to be (2.7,3.4). How many observations must be made so that 90% confidence interval will specify the mean to within 0.2
October 6, 2011 by Prakash

Data Management
A confident and boastful coach claims that on the next league game the odds of his team winning are 3:1; the odds against losing are 5:1; and the odds against a tie are 7:1. Can these odds be right? Explain.
January 21, 2014 by Alejandro

Statistics
A confidence interval was used to estimate the proportion of statistics students that are females. A random sample of 72 statistics students generated the following 90% confidence Interval: (.43, .63). based on the interval above, is the population proportion of females equal ...
November 22, 2010 by Anonymous

statistics
a companys ceo wanted to estimate the percentage of defective product per shipment. in a sample contianing 600 products he found 45 defective product. a. find 99% confidence interval for the true porporton of defective product show calcultions and explain process used to ...
August 23, 2011 by crystal

STATISTICS
The following table comes from a hypothetical case-control study that compared adults with moderate-to-severe acne (cases) to adults without acne (controls). The researchers examined the relationship between smoking and acne. The prevalence of moderate-to-severe acne in the ...
August 6, 2013 by Susie

Statistics
These are the only ones that I am having problems with. Please help.. 8.You are given the sample mean and the sample standard deviation. Use this information to construct the 90% and the 95% confidence intervals for the population mean. Interpret the results and compare the ...
February 17, 2013 by Katie

Statistics
A scientist in Smallville tested the cholesterol of a random sample of 35 town residents. He constructed the following confidence interval: t-interval for μ: with 99.00% Confidence: 188 < μ(Cholesterol) < 206 What is the margin of error? A) 18 B) 9 C) 1.09 D) ...
November 6, 2013 by Katelyn

Statistics
Which is true about a 99% confidence interval for a population proportion based on a given sample? I. We are 99% confident that the population proportion is in our interval. II. There is a 99% chance that our interval contains the sample proportion. III. The interval is wider ...
October 28, 2013 by Fred

stats
In a poll of 100 adults, 45% reported they believed in faith healing. (USA Today, 20 April 1998). Based on this survey, a 95% confidence interval for the proportion in the population who believe in faith healing is about 42% to 48%. If this poll had been based instead on ...
June 23, 2010 by Anonymous

stats
In order to make sure that their bags of chips are of sufficient weight, the Chipper Chip Company try to fill their 200 gram bags of chips with more than 203 grams. You have been given the task of investigating what proportion of bags produced do have over 203 grams of chips ...
October 30, 2010 by lollzzz

statistics
In a sample of 100 steel wires the average breaking strength is 50 kN, with a standard deviation of 2 kN. a. Find a 95% confidence interval for the mean breaking strength of this type of wire. b. An engineer claims that the mean breaking strength is between 49.7 kN and 50.3 ...
October 29, 2011 by Don't get it!! :(

Stats
In a study of children with a particular disorder, parents were asked to rate their child on a variety of items related to how well their child performs different tasks. One item was "Has difficulty organizing work," rated on a five-point scale of 0 to 4 with 0 corresponding ...
July 9, 2012 by James

Math Statistics
Students enrolled in an introductory statistics course at a university were asked to take a survey that indicated whether the student has a visual or verbal learning style. Of the 39 students who took the survey, 25 were judged to have a visual learning style and 14 were ...
July 25, 2013 by James

statistics
A school psychologist is trying to determine the lower boundary of a confidence interval for a IQ measure that has a mean of 100 and a standard deviation of 30 and a sample size of 100. What is the lower boundary if she was to create a 95% confidence interval?
July 1, 2011 by Haywood

Statistics
A 95% confidence interval for a population mean, ?, is given as (18.985, 21.015). This confidence interval is based on a simple random sample of 36 observations. Calculate the sample mean, x ?, and the sample standard deviation, s. Assume that all assumptions and conditions ...
June 18, 2012 by Mike

Statistics
Direct mail advertisers send solicitations (a.k.a. "junk mail") to thousands of potential customers in the hope that some will buy the company's product. The response rate is usually quite low. Suppose a company wants to test the response to a new flyer, and sends it to 1000 ...
March 13, 2013 by MeSue

Statistics
A survey organization takes a simple random sample of 625 households from a city of 80,000 households. On the average, there are 2.30 persons per sample household, and the SD is 1.75. Say whether each of the following statements are True or false and explain (a) The SE for the...
October 26, 2011 by Joyann

statistics
A sample of 134 golfers showed that their average score on a particular golf course was 87.43 with a standard deviation of 4.53. Answer each of the following (show all work and state the final answer to at least two decimal places.): (A) Find the 99% confidence interval of the...
November 2, 2010 by Valerie

statistics
A sample of 106 golfers showed that their average score on a particular golf course was 87.98 with a standard deviation of 5.39. Answer each of the following (show all work and state the final answer to at least two decimal places.): (A) Find the 90% confidence interval of the...
September 2, 2011 by Laynette

Statistics
A study of 420,048 cell phone users found that 135 of them developed cancer of the brain or nervous system. prior to this study of cell phone use the rate of such cancer was found to be 0.0333% for those not using cell phones. Complete parts (a) and (b) a. use the sample data ...
April 30, 2013 by Rob

statistics
Lorraine was in a hurry when she computed a confidence interval for μ. Because σ was not known, she used a Student's t distribution. However, she accidentally used degrees of freedom n instead of n - 1. Will her confidence interval be longer or shorter than one found...
February 18, 2012 by jr

Math
Suppose a population is sampled and the sample mean is 16.8. The sample standard deviation is 6.0 I am to assume the sample is larger than 30) and the sample size is 65. How do I calculate 95% and 98% confidence intervals. State which interval wider and why please. How would I...
February 13, 2013 by Mandi

Statistics
A researcher performs a hypothesis test to test the claim that among girls aged 9-10, the mean score on a particular aptitude test differs from 72, which is the mean score for boys of the same age. Data were collected from a random sample of 43 girls aged 9-10 years and the 95...
November 8, 2013 by Katie

Statistics
In a study to estimate a population mean, i start with a sample size 10 and calculate the 95% confidence interval. Suppose i am not satisfied with the size of the confidence interval and want to reduce it by half. Give an estimate of sample size that i need.
August 23, 2010 by Zodra

statistics
Using the 95% level of confidence, what is the confidence interval for the proportion of households represented at a town meeting
April 21, 2014 by Jay

Statistics
An opinion poll asks a random sample of 100 college seniors how they view their job prospects. In all, 53 say "Good." The 95% confidence interval has a margin of error of 9.9%. The sample used actually included 130 college seniors but 30 of the seniors refused to answer. This ...
November 11, 2013 by Samantha

Confidence Intervals
Over the last 15 Major League Baseball seasons, the mean number of strikeouts by the American League leader is 258.5. Assuming that the number of strikeouts by the league leader is normally distributed and the standard deviation for all seasons in all leagues is 34.9, find the...
June 20, 2008 by melanie

statistics
A consumer magazine has contacted a simple random sample of 33 owners of a certain model of automobile and asked each owner how many defects had to be corrected with in the first 2 months of ownership. The average number of defects was x with (with line over the x)=3.7, with a...
October 15, 2009 by Tammy

Statistics-Confidence Interval
Can someone please help me on how to work this out?? I'm so super confused. Thanks! A professor at Kaplan University claims that the average age of all Kaplan students is 36 years old. Use a 95% confidence interval to test the professor's claim. Is the professor's claim ...
January 16, 2012 by Sara

Math - Odds
If you toss three coins, what are the odds in favor of getting exactly two tails and one head? A. 3:8 B. 3:5 C. 5:3 D. 8:3 can you explain this? i can do odds but this is confusing me.
May 28, 2013 by bubbie

statistics
Find the critical value zc necessary to form a confidence interval at the given level of confidence. a. 90% = 1.645 b. 85% = 1.8025
April 1, 2010 by looking for someone to varify my work please

Statistics
How would I find the confidence level (in %) if I am given the standard deviation, size of the random sample, and confidence interval?
April 3, 2013 by C

Math
How would I find the confidence level (in %) if I am given the standard deviation, size of the random sample, and confidence interval?
April 3, 2013 by C

STATISTICS
Bacterial samples were taken from several surfaces in a daycare and incubated in petri dishes. After that the number of bateria colonies were counted, with the following results 412, 437, 425, 476, 451, 483. 1) construct a 95% confidence interval for the mean number of ...
October 11, 2007 by Keirson

statistics
A data set includes body temperatures of healthy adult humans for which x= 98.2 and s=0.64 F. Complete parts a) and b) below a) what is the best point estimate of the mean body temperature of all healthy humans? The best point estimate is F. b) Using the sample statistics, ...
November 19, 2013 by anonymous

math
The new Twinkle bulb is being developed to last more than 1000 hours. A random sample of 100 of these new bulbs is selected from the production line. It was found that 48 lasted more than 1000 hours. Find the point estimate for the population proportion, the margin of error ...
April 17, 2011 by Heaven

stats
Use the given degree of confidence and sample data to construct a confidence interval for the population proportion p. 1) n = 128, x = 93; 90 percent
April 15, 2013 by t

Statistics
Please help!! I have no idea how to do this question. 14. A sample of 40 CDs from your collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes a. Construct the 95 percent confidence interval for the mean. b. Construct the 95 percent ...
October 31, 2011 by Kristi

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