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8 Estimation

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In hypothesis tests, the purpose was to make a decision about a parameter, in terms of it being greater than, less than, or not equal to a value. But what if you want to actually know what the parameter is. You need to do estimation. There are two types of estimation – point estimator and confidence interval. The American Statistical Association (ASA) is recommending that confidence intervals are the process that should be followed when analyzing data.

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Basics of Confidence Intervals

image𝑝̂
imageπ‘₯Μ„
imageπœ‡
A point estimator is just the statistic that you have calculated previously. As an example, when you wanted to estimate the population mean, , the point estimator is the sample mean, . To estimate the population proportion, p, you use the sample proportion, . In general, if you want to estimate any population parameter, we will call it πœƒ, you use the sample statistic, πœƒΜ‚.

Point estimators are really easy to find, but they have some drawbacks. First, if you have a large sample size, then the estimate is better. But with a point estimator, you don’t know what the sample size is. Also, you don’t know how accurate the estimate is. Both of these problems are solved with a confidence interval.

imageπœƒΜ‚ Β± πΈπœƒΜ‚
Confidence interval: This is where you have an interval surrounding your parameter, and the interval has a chance of being a true statement. In general, a confidence interval looks like:, where is the point estimator and E is the margin of error term that is added and subtracted from the point estimator. Thus making an interval.

Interpreting a confidence interval:

The statistical interpretation is that the confidence interval has a probability

𝐢 = (1 βˆ’ 𝛼) (where 𝛼 is the complement of the confidence level) of containing 263

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image0.65 < 𝑝 < 0.73
the population parameter. As an example, if you have a 95% confidence interval of, then you would say, β€œyou are 95% confident that the interval

0.65 to 0.73 contains the true population proportion.” This means that if you have 100 intervals, 95 of them will contain the true proportion, and 5 will not. The wrong interpretation is that there is a 95% confidence that the true value of p will fall between 0.65 and 0.73. The reason that this interpretation is wrong is that the true value is fixed out there somewhere. You are trying to capture it with this interval. So this is the chance that your interval captures it, and not that the true value falls in the interval.

There is also a real world interpretation that depends on the situation. It is where you are telling people what numbers you found the parameter to lie between. So your real world is where you tell what values your parameter is between. There is no probability attached to this statement. That probability is in the statistical interpretation.

image𝛼2𝛼
image𝐢 = 1 βˆ’ 𝛼𝛼
imageπ»π‘Ž ∢ πœ‡ β‰  πœ‡π‘œ
imageπ»π‘Ž ∢ πœ‡ < πœ‡π‘œπ›Ό
imageπ»π‘Ž ∢ πœ‡ β‰  πœ‡π‘œπ›Ό
The common probabilities used for confidence intervals are 90%, 95%, and 99%. These are known as the confidence level. The confidence level and the alpha level are related. If you are conducting a hypothesis test with, then the confidence level is. This is because theis both tails and the confidence level is area between the two tails. As an example, for a hypothesis testwithequal to 0.10, the confidence level would be 0.90 or 90%. If you have a hypothesis test with, then youris only one tail of the curve. Because of symmetry the other tail is also. You have with both tails. So the confidence level, which is the area between the two tails, is 𝐢 βˆ’ 2𝛼.

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Example: Stating the Statistical and Real World In- terpretations for a Confidence Interval

  • image26 < πœ‡ < 28
    Suppose you have a 95% confidence interval for the mean age a woman gets married in 2013 is. State the statistical and real world interpretations of this statement.

Solution:

Statistical Interpretation: You are 95% confident that the interval contains the mean age in 2013 that a woman gets married.

Real World Interpretation: The mean age that a woman married in 2013 is between 26 and 28 years of age.

  • image0.35 < 𝑝 < 0.41
    Suppose a 99% confidence interval for the proportion of Americans who have tried marijuana as of 2013 is. State the statistical and real world interpretations of this statement.

Solution:

Statistical Interpretation: You are 99% confident that the interval contains the proportion of Americans who have tried marijuana as of 2013.

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  • BASICS OF CONFIDENCE INTERVALS265

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Real World Interpretation: The proportion of Americans who have tried mari- juana as of 2013 is between 0.35 and 0.41.

One last thing to know about confidence is how the sample size and confidence level affect how wide the interval is. The following discussion demonstrates what happens to the width of the interval as you get more confident.

Think about shooting an arrow into the target. Suppose you are really good at that and that you have a 90% chance of hitting the bull’s eye. Now the bull’s eye is very small. Since you hit the bull’s eye approximately 90% of the time, then you probably hit inside the next ring out 95% of the time. You have a better chance of doing this, but the circle is bigger. You probably have a 99% chance of hitting the target, but that is a much bigger circle to hit. You can see, as your confidence in hitting the target increases, the circle you hit gets bigger. The same is true for confidence intervals. This is demonstrated in figure #8.1.1.

image

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Figure 8.1: figure of Affect of Confidence Level

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The higher level of confidence makes a wider interval. There’s a trade off between width and confidence level. You can be really confident about your answer but your answer will not be very precise. Or you can have a precise answer (small margin of error) but not be very confident about your answer.

Now look at how the sample size affects the size of the interval. Suppose figure #8.1.2 represents confidence intervals calculated on a 95% interval. A larger sample size from a representative sample makes the width of the interval nar- rower. This makes sense. Large samples are closer to the true population so the point estimate is pretty close to the true value.

Now you know everything you need to know about confidence intervals except for the actual formula. The formula depends on which parameter you are trying to estimate. With different situations you will be given the confidence interval for that parameter.

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Homework

  • Suppose you compute a confidence interval with a sample size of 25. What will happen to the confidence interval if the sample size increases to 50?

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image

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Figure 8.2: Figure of Affect of Sample Size

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  • Suppose you compute a 95% confidence interval. What will happen to the confidence interval if you increase the confidence level to 99%?
  • Suppose you compute a 95% confidence interval. What will happen to the confidence interval if you decrease the confidence level to 90%?
  • Suppose you compute a confidence interval with a sample size of 100. What will happen to the confidence interval if the sample size decreases to 80?
  • image6353π‘˜π‘š < πœ‡ < 6384π‘˜π‘šπœ‡
    A 95% confidence interval is, where is the mean diameter of the Earth. State the statistical interpretation.
  • image6353π‘˜π‘š < πœ‡ < 6384π‘˜π‘šπœ‡
    A 95% confidence interval is, where is the mean diameter of the Earth. State the real world interpretation.
  • image0.52 < 𝑝 < 0.60
    In 2013, Gallup conducted a poll and found a 95% confidence interval of, where p is the proportion of Americans who believe it is the government’s responsibility for health care. Give the real world interpretation.
  • image0.52 < 𝑝 < 0.60
    In 2013, Gallup conducted a poll and found a 95% confidence interval of, where p is the proportion of Americans who believe it is the government’s responsibility for health care. Give the statistical interpretation.

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One-Sample Interval for the Proportion

Suppose you want to estimate the population proportion, p. As an example you may be curious what proportion of students at your school smoke. Or you could wonder what is the proportion of accidents caused by teenage drivers who do not have a drivers’ education class.

Confidence Interval for One Population Proportion (1-Prop Interval)

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  • State the random variable and the parameter in words.

x = number of successes

p = proportion of successes

  • State and check the assumptions for the confidence interval
  • A simple random sample of size n is taken.
  • The condition for the binomial distribution are satisfied
  • image𝑝̂
    image𝑛 βˆ— 𝑝̂ β‰₯ 5𝑛 βˆ— π‘žΜ‚ β‰₯ 5π‘žΜ‚ = 1 βˆ’ 𝑝̂
    image𝑝̂
    image𝑝̂
    The sampling distribution of can be approximated by a normal dis- tributed. To determine the sampling distribution of is normally dis- tributed, you need to show thatand ,where. If this requirement is true, then the sampling distribution of is well ap- proximated by a normal curve. (In reality this is not really true, since the correct assumption deals with p. However, in a confidence interval you do not know p, so you must use 𝑝̂.)
  • Find the sample statistic and the confidence interval This will be conducted using R Studio. The command is

prop.test(r, n, conf.Level=C as a decimal)

  • Statistical Interpretation: In general this looks like, β€œyou are C% confident that 𝑝̂ Β± 𝐸 contains the true proportion.”
  • Real World Interpretation: This is where you state what interval contains the true proportion.

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Example:Confidence Interval for the Population Proportion

A concern was raised in Australia that the percentage of deaths of Aboriginal prisoners was higher than the percent of deaths of non-Aboriginal prisoners, which is 0.27%. A sample of six years (1990-1995) of data was collected, and it was found that out of 14,495 Aboriginal prisoners, 51 died (”Indigenous deaths in,” 1996). Find a 95% confidence interval for the proportion of Aboriginal prisoners who died.

Solution:

  • State the random variable and the parameter in words.

x = number of Aboriginal prisoners who die

p = proportion of Aboriginal prisoners who die

  • State and check the assumptions for the confidence interval
  • A simple random sample of 14,495 Aboriginal prisoners was taken. Check: The sample was not a random sample, since it was data from six years. It

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is the numbers for all prisoners in these six years, but the six years were not picked at random. Unless there was something special about the six years that were chosen, the sample is probably a representative sample. This assumption is probably met.

  • The properties of the binomial experiment have been met. Check: There are 14,495 prisoners in this case. The prisoners are all Aboriginals, so you are not mixing Aboriginal with non-Aboriginal prisoners. There are only two outcomes, either the prisoner dies or doesn’t. The chance that one prisoner dies over another may not be constant, but if you consider all prisoners the same, then it may be close to the same probability. Thus the properties of the binomial experiment are satisfied
  • imagebution. Check: π‘Μ‚βˆ—π‘› =βˆ—14495 = 51 β‰₯ 5 and π‘žΜ‚βˆ—π‘› =βˆ—14495 =
    image𝑝̂
    The sampling distribution ofcan be approximated with a normal distri-

51 14495βˆ’51

imagenormal distribution.
14444 β‰₯ 5. The sampl1i4n4g95distribution of 𝑝̂ can be appro1x4i4m95ated with a

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  • Find the sample statistic and the confidence interval

The command in R Studio for a confidence interval for a proportion is

prop.test(51,14495, conf.level = 0.95)

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##

## 1-sample proportions test with continuity correction ##

## data: 51 out of 14495

## X-squared = 14290, df = 1, p-value < 2.2e-16

## alternative hypothesis: true p is not equal to 0.5 ## 95 percent confidence interval:

## 0.002647440 0.004661881

## sample estimates:

##p

## 0.003518455

the 95% confidence level is 0.002647440 < 𝑝 < 0.004661881.

  • Statistical Interpretation:You are 95% confident that the interval

0h.a0v0e26di<ed𝑝in<p0r.i0so0n4.7 contains the proportion of Aboriginal prisoners who

  • Real World Interpretation: The proportion of Aboriginal prisoners who died in prison is between 0.26% and 0.47%.

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Example:Confidence Interval for the Population Proportion

A researcher who is studying the effects of income levels on breastfeeding of infants hypothesizes that countries with a low income level have a different

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rate of infant breastfeeding than higher income countries. It is known that in Germany, considered a high-income country by the World Bank, 22% of all babies are breastfeed. In Tajikistan, considered a low-income country by the World Bank, researchers found that in a random sample of 500 new mothers that 125 were breastfeeding their infant. Find a 90% confidence interval of the proportion of mothers in low-income countries who breastfeed their infants?

Solution:

  • State you random variable and the parameter in words.

x = number of woman who breastfeed in a low-income country

p = proportion of woman who breastfeed in a low-income country

  • State and check the assumptions for the confidence interval
  • A simple random sample of 500 breastfeeding habits of woman in a low- income country was taken. Check: This was stated in the problem.
  • The properties of a Binomial Experiment have been met. check: There were 500 women in the study. The women are considered identical, though they probably have some differences. There are only two outcomes, either the woman breastfeeds or she doesn’t. The probability of a woman breast- feeding is probably not the same for each woman, but it is probably not very different for each woman. The conditions for the binomial distribu- tion are satisfied
  • imagetributed. Check:𝑛 βˆ— 𝑝̂ = 500 βˆ—= 125 β‰₯ 5 and 𝑛 βˆ— π‘žΜ‚ = 500 βˆ—=
    image𝑝
    The sampling distribution ofcan be approximated with a normal dis-

125500βˆ’125

imagenormal distribution.
375 β‰₯ 5, so the sampling dis5t0r0ibution of 𝑝̂ is well approximate5d00by a

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4. Find the sample statistic and confidence interval On R studio, use the following command

prop.test(125, 500, conf.level = .90)

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##

## 1-sample proportions test with continuity correction ##

## data: 125 out of 500

## X-squared = 124, df = 1, p-value < 2.2e-16

## alternative hypothesis: true p is not equal to 0.5 ## 90 percent confidence interval:

## 0.2185980 0.2841772

## sample estimates:

##p

## 0.25

90% confidence interval for p is 0.2185980 < 𝑝 < 0.2841772.

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image0.2841772
image0.2185980 < 𝑝 <
4. Statistical Interpretation: You are 90% confident that

contains the proportion of women in low-income countries who breastfeed their infants.

5. Real World Interpretation: The proportion of women in low-income coun- tries who breastfeed their infants is between 0.219 and 0.284.

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Homework

In each problem show all steps of the confidence interval. If some of the assumptions are not met, note that the results of the interval may not be correct and then continue the process of the confidence interval.

  • The Arizona Republic/Morrison/Cronkite News poll published on Mon- day, October 20, 2016, found 390 of the registered voters surveyed favor Proposition 205, which would legalize marijuana for adults. The statewide telephone poll surveyed 779 registered voters between Oct. 10 and Oct. 15. (Sanchez, 2016) Find a 99% confidence interval for the proportion of Ari- zona’s who supported legalizing marijuana for adults.
  • In November of 1997, Australians were asked if they thought unemploy- ment would increase. At that time 284 out of 631 said that they thought unemployment would increase (”Morgan gallup poll,” 2013). Estimate the proportion of Australians in November 1997 who believed unemployment would increase using a 95% confidence interval?
  • According to the February 2008 Federal Trade Commission report on con- sumer fraud and identity theft, Arkansas had 1,601 complaints of identity theft out of 3,482 consumer complaints (”Consumer fraud and,” 2008). Calculate a 90% confidence interval for the proportion of identity theft in Arkansas.
  • According to the February 2008 Federal Trade Commission report on con- sumer fraud and identity theft, Alaska had 321 complaints of identity theft out of 1,432 consumer complaints (”Consumer fraud and,” 2008). Calculate a 90% confidence interval for the proportion of identity theft in Alaska.
  • In 2013, the Gallup poll asked 1,039 American adults if they believe there was a conspiracy in the assassination of President Kennedy, and found that 634 believe there was a conspiracy (”Gallup news service,” 2013). Estimate the proportion of American’s who believe in this conspiracy using a 98% confidence interval.
  • In 2008, there were 507 children in Arizona out of 32,601 who were diag- nosed with Autism Spectrum Disorder (ASD) (”Autism and developmen- tal,” 2008). Find the proportion of ASD in Arizona with a confidence level of 99%.

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One-Sample Interval for the Mean

Suppose you want to estimate the mean height of Americans, or you want to estimate the mean salary of college graduates. A confidence interval for the mean would be the way to estimate these means.

Confidence Interval for One Population Mean (t-Interval)

  • State the random variable and the parameter in words. x = random variable

πœ‡ = mean of random variable

  • State and check the assumptions for the confidence interval
  • A random sample of size n is taken.
  • The population of the random variable is normally distributed, though the t-test is fairly robust to the assumption if the sample size is large. This means that if this assumption isn’t met, but your sample size is quite large, then the results of the t-test are valid.
  • Find the sample statistic and confidence interval

Use R Studio to find the confidence interval. The command is

t.test(~variable, data= Data Frame, conf.level=C as a decimal)

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  • Statistical Interpretation: In general this looks like, β€œYou are C% confident that the interval contains the true mean.”
  • Real World Interpretation: This is where you state what interval contains the true mean.

How to check the assumptions of confidence interval:

In order for the confidence interval to be valid, the assumptions of the test must be true. Whenever you run a confidence interval, you must make sure the assumptions are true. You need to check them. Here is how you do this:

  • For the assumption that the sample is a random sample, describe how you took the sample. Make sure your sampling technique is random.
  • For the assumption that population is normal, remember the process of assessing normality from chapter 6.

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Example:Confidence Interval for the Population Mean

A random sample of 50 body mass index (BMI) were taken from the NHANES Data frame. Estimate the mean BMI of Americans at the 95% level.

Table #8.3.1: BMI of Americans

imagesample_NHANES_50<-sample_n(NHANES, size=50)head(sample_NHANES_50)

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## # A tibble: 6 x 76

image##165676 2011_12 female35″ 30-39″NAWhite##252496 2009_10 female60″ 60-69″721White##369798 2011_12 female21″ 20-29″NAWhite##452326 2009_10 male28″ 20-29″343White##553524 2009_10 female39″ 30-39″471White##654437 2009_10 female51″ 50-59″619Other###… with 69 more variables: Race3 <fct>, Education <fct>,###MaritalStatus <fct>, HHIncome <fct>, HHIncomeMid <int>,###Poverty <dbl>, HomeRooms <int>, HomeOwn <fct>,###Work <fct>, Weight <dbl>, Length <dbl>, HeadCirc <dbl>,###Height <dbl>, BMI <dbl>, BMICatUnder20yrs <fct>,###BMI_WHO <fct>, Pulse <int>, BPSysAve <int>,###BPDiaAve <int>, BPSys1 <int>, BPDia1 <int>,###BPSys2 <int>, BPDia2 <int>, BPSys3 <int>, BPDia3 <int>,###Testosterone <dbl>, DirectChol <dbl>, TotChol <dbl>,###UrineVol1 <int>, UrineFlow1 <dbl>, UrineVol2 <int>,###UrineFlow2 <dbl>, Diabetes <fct>, DiabetesAge <int>,###HealthGen <fct>, DaysPhysHlthBad <int>,###DaysMentHlthBad <int>, LittleInterest <fct>,###Depressed <fct>, nPregnancies <int>, nBabies <int>,###Age1stBaby <int>, SleepHrsNight <int>,###SleepTrouble <fct>, PhysActive <fct>,###PhysActiveDays <int>, TVHrsDay <fct>, CompHrsDay <fct>,###TVHrsDayChild <int>, CompHrsDayChild <int>,###Alcohol12PlusYr <fct>, AlcoholDay <int>,###AlcoholYear <int>, SmokeNow <fct>, Smoke100 <fct>,###Smoke100n <fct>, SmokeAge <int>, Marijuana <fct>,###AgeFirstMarij <int>, RegularMarij <fct>,###AgeRegMarij <int>, HardDrugs <fct>, SexEver <fct>,###SexAge <int>, SexNumPartnLife <int>,###SexNumPartYear <int>, SameSex <fct>,###SexOrientation <fct>, PregnantNow <fct>
##ID SurveyYr GenderAge AgeDecade AgeMonths Race1 ##<int> <fct><fct> <int> <fct><int> <fct>

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Solution:

  • State the random variable and the parameter in words.

x = BMI of an American

πœ‡ = mean BMI of Americans

  • State and check the assumptions for the confidence interval
  • A random sample of 50 BMI levels was taken. Check: A random sample was taken from the NHANES data frame using R Studio
  • The population of BMI levels is normally distributed. Check:

gf_density(~BMI, data=sample_NHANES_50)

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image
0.05

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0.03

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imagedensity
0.02

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0.01

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0.00

203040

BMI

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Figure 8.3: Density Plot of BMI from NHANES sample

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gf_qq(~BMI, data=sample_NHANES_50)

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The density plot looks somewhat skewed right and the normal quantile plot looks somewhat linear. However, there doesn’t seem to be strong evidence that the sample comes from a population that is normally distributed. However, since the sample is moderate to large, the t-test is robust to this assumption not being met. So the results of the test are probably valid.

4. Find the sample statistic and confidence interval

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image
40

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imagesample
30

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20

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βˆ’2βˆ’1012

theoretical

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Figure 8.4: Normal Quantile Plot of BMI from NHANES sample

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On R Studio, the command would be

t.test(~BMI, data= sample_NHANES_50, conf.level=0.95)

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##

## One Sample t-test ##

## data: BMI

## t = 25.818, df = 48, p-value < 2.2e-16

## alternative hypothesis: true mean is not equal to 0 ## 95 percent confidence interval:

## 25.08079 29.31717

## sample estimates:

## mean of x ## 27.19898

The sample statistic is the mean of x in the output, and confidence interval is under the words 95 percent confidence interval.

4. Statistical Interpretation: You are 95% confident that 24.87190 < πœ‡ < 28.71422 contains the mean BMI of Americans.

5. Real World Interpretation: The mean BMI of Americans is between 24.87 and 28.71 π‘˜π‘”/π‘š2.

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imageπ‘˜π‘”/π‘š
Notice that in example #7.3.2, you were asked if the mean BMI of Americans was different from Australians’ mean BMI of 27.22. The interval that example #8.3.1 calculated does contain the value of 27.2. So you can’t say that Americans’ mean BMI and Australians’ mean BMI are different.This means that you can just use confidence intervals and not conduct hypothesis tests at all if you prefer.

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Example:Confidence Interval for the Population Mean

The data in table #8.3.2 are the life expectancies for all people in European countries (”WHO life expectancy,” 2013). Table #8.3.3 filtered the data frame for just males and just year 2000. The year 2000 was randomly chosen as the year to use. Estimate the mean life expectancy for a man in Europe at the 99% level.

Table #8.3.2: Life Expectancies for European Countries

imageExpectancy<-read.csv( “https://krkozak.github.io/MAT160/Life_expectancy_Europe.csv”)head(Expectancy)

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##

year

WHO_region country

sex

expect

##

1 1990

Europe Albania

Male

67

##

2 1990

Europe Albania

Female

71

##

3 1990

Europe Albania

Both sexes

69

##

4 2000

Europe Albania

Male

68

##

5 2000

Europe Albania

Female

73

##

6 2000

Europe Albania

Both sexes

71

Table #8.3.3: Life Expectancies of males in European Countries in 2000

imageExpectancy_male<- Expectancy%>%filter(sex==”Male”, year==”2000″)head(Expectancy_male)

##year WHO_regioncountry sex expect

## 1 2000

EuropeAlbania Male

68

## 2 2000

EuropeAndorra Male

76

## 3 2000

EuropeArmenia Male

68

## 4 2000

EuropeAustria Male

75

## 5 2000

Europe Azerbaijan Male

64

## 6 2000

EuropeBelarus Male

63

Code book for data frame Expectancy See example 7.3.3 in Section 7.3

Solution:

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  • State the random variable and the parameter in words.

x = life expectancy for a European man

πœ‡ = mean life expectancy for European men

  • State and check the assumptions for the confidence interval
  • A random sample of 53 life expectancies of European men in 2000 was taken. Check: The data is actually all of the life expectancies for every country that is considered part of Europe by the World Health Organiza- tion in the year 2000. Since the year 2000 was picked at random, then the sample is a random sample.
  • The distribution of life expectancies of European men in 2000 is normally distributed. Check:

gf_density(~expect, data=Expectancy_male)

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image
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imagedensity
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0.02

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0.00

60657075

expect

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Figure 8.5: (ref:expactancy-male8-density-cap)

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gf_qq(~expect, data=Expectancy_male)

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This sample does not appear to come from a population that is normally dis- tributed. This sample is moderate to large, so it is good that the t-test is robust.

  • Find the sample statistic and confidence interval

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image
75

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imagesample
70

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65

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60

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βˆ’2βˆ’1012

theoretical

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Figure 8.6: Normal Quntile Plot of Life Expectancies of Males in Europe in 2000

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On R Studio, the command would be

t.test(~expect, data=Expectancy_male, conf.level=0.99)

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##

## One Sample t-test ##

## data: expect

## t = 90.919, df = 52, p-value < 2.2e-16

## alternative hypothesis: true mean is not equal to 0 ## 99 percent confidence interval:

## 68.60071 72.75778

## sample estimates:

## mean of x ## 70.67925

Sample statistic is 70.68 years, and the confidence interval is 68.60071 < πœ‡ < 72.75778.

  • Statistical Interpretation: You are 99% confident that 68.60071 < πœ‡ < 72.75778 contains the mean life expectancy of European men.
  • Real World Interpretation: The mean life expectancy of European men is

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between 68.60 and 72.76 years.

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Homework

** In each problem show all steps of the confidence interval. If some of the assumptions are not met, note that the results of the interval may not be correct and then continue the process of the confidence interval.**

  • The Kyoto Protocol was signed in 1997, and required countries to start re- ducing their carbon emissions. The protocol became enforceable in Febru- ary 2005. Table 8.3.4 contains a random sample of CO2 emissions in 2010 (CO2 emissions (metric tons per capita), 2018). Find a 99% confidence interval for the mean CO-2 emissions in 2010.

Table #8.3.4: CO2 Emissions (in metric tons per capita) in 2010

imageEmission <- read.csv( “https://krkozak.github.io/MAT160/CO2_emission.csv”)head(Emission)

Β 

##

country

y1960

y1961

y1962

y1963

##

1

Aruba

NA

NA

NA

NA

##

2

Afghanistan

0.04605671

0.05358884

0.07372083

0.07416072

##

3

Angola

0.10083534

0.08220380

0.21053148

0.20273730

##

4

Albania

1.25819493

1.37418605

1.43995596

1.18168114

##

5

Andorra

NA

NA

NA

NA

##

6

Arab World

0.64573587

0.68746538

0.76357363

0.87823769

##

Β 

y1964

y1965

y1966

y1967

y1968

##

1

NA

NA

NA

NA

NA

##

2

0.08617361

0.1012849

0.1073989

0.1234095

0.1151425

##

3

0.21356035

0.2058909

0.2689414

0.1721017

0.2897181

##

4

1.11174196

1.1660990

1.3330555

1.3637463

1.5195513

##

5

NA

NA

NA

NA

NA

##

6

1.00305335

1.1705403

1.2781736

1.3374436

1.5522420

##

Β 

y1969

y1970

y1971

y1972

y1973

##

1

NA

NA

NA

NA

NA

##

2

0.08650986

0.1496515

0.1652083

0.1299956

0.1353666

##

3

0.48023402

0.6082236

0.5645482

0.7212460

0.7512399

##

4

1.55896757

1.7532399

1.9894979

2.5159144

2.3038974

##

5

NA

NA

NA

NA

NA

##

6

1.79866893

1.8103078

2.0037220

2.1208746

2.4095329

##

Β 

y1974y1975y1976y1977y1978

##

1

NANANANANA

##

2

0.1545032 0.1676124 0.1535579 0.1815222 0.1618942

##

3

0.7207764 0.6285689 0.4513535 0.4692212 0.6947369

##

4

1.8490067 1.9106336 2.0135846 2.2758764 2.5306250

##

5

NANANANANA

##

6

2.2858907 2.1967827 2.5843424 2.6487624 2.7623331

Β 

Β 

##

y1979

y1980

y1981

y1982

y1983

##

1

NA

NA

NA

NA

NA

##

2

0.1670664

0.1317829

0.1506147

0.1631039

0.2012243

##

3

0.6830629

0.6409664

0.6111351

0.5193546

0.5513486

##

4

2.8982085

1.9350583

2.6930239

2.6248568

2.6832399

##

5

NA

NA

NA

NA

NA

##

6

2.8636143

3.0928915

2.9302350

2.7231544

2.8165670

##

Β 

y1984

y1985

y1986

y1987

y1988

##

1

NA

NA

2.8683194

7.2351980

10.0261792

##

2

0.2319613

0.2939569

0.2677719

0.2692296

0.2468233

##

3

0.5209829

0.4719028

0.4516189

0.5440851

0.4635083

##

4

2.6942914

2.6580154

2.6653562

2.4140608

2.3315985

##

5

NA

NA

NA

NA

NA

##

6

2.9813539

3.0618504

3.2844996

3.1978064

3.2950428

##

y1989

y1990

y1991

y1992

y1993

##

1

10.6347326

26.3745032 26.0461298 21.44255880 22.00078616

##

2

0.2338822

0.2106434 0.1833636 0.09619658 0.08508711

##

3

0.4372955

0.4317436 0.4155308 0.41052293 0.44172110

##

4

2.7832431

1.6781067 1.3122126 0.77472491 0.72379029

##

5

NA

7.4673357 7.1824566 6.91205339 6.73605485

##

6

3.2566742

3.0169588 3.2366449 3.41548491 3.66944563

##

y1994

y1995

y1996

y1997

##

1

21.03624511

20.77193616

20.31835337

20.42681771

##

2

0.07580649

0.06863986

0.06243461

0.05664234

##

3

0.28811907

0.78703255

0.72623346

0.49636125

##

4

0.60020371

0.65453713

0.63662531

0.49036506

##

5

6.49420042

6.66205168

7.06507147

7.23971272

##

6

3.67435821

3.42400952

3.32830368

3.14553220

##

Β 

y1998

y1999

y2000

y2001

##

1

20.58766915

20.31156677

26.19487524

25.93402441

##

2

0.05276322

0.04072254

0.03723478

0.03784614

##

3

0.47581516

0.57708291

0.58196150

0.57431605

##

4

0.56027144

0.96016441

0.97817468

1.05330418

##

5

7.66078389

7.97545440

8.01928429

7.78695000

##

6

3.34996719

3.32834106

3.70385708

3.60795615

##

Β 

y2002

y2003

y2004

y2005

##

1

25.67116178

26.42045209

26.51729342

27.20070778

Β 

##

2

0.04737732

0.05048134

0.03841004

0.05174397

Β 

##

3

0.72295888

0.50022540

1.00187812

0.98573636

Β 

##

4

1.22954071

1.41269720

1.37621273

1.41249821

Β 

##

5

7.59061514

7.31576071

7.35862494

7.29987194

Β 

##

6

3.60461275

3.79646741

4.06856241

4.18567731

Β 

##

Β 

y2006

y2007

y2008

y2009

y2010

##

1

26.94772597

27.89502282

26.2295527 25.9153221 24.6705289

##

2

0.06242753

0.08389281

0.1517209 0.2383985 0.2899876

##

3

1.10501903

1.20313400

1.1850005 1.2344251 1.2440915

Β 

Β 

##

4

1.30257637 1.32233486

1.4843111

1.4956002

1.5785736

##

5

6.74605213 6.51938706

6.4278100

6.1215799

6.1225947

##

6

4.28571918 4.11714755

4.4089483

4.5620151

4.6368134

##

Β 

y2011y2012

y2013

y2014 y2015

y2016

##

1

24.5075162

13.1577223

8.353561

8.4100642

NA

NA

##

2

0.4064242

0.3451488

0.310341

0.2939464

NA

NA

##

3

1.2526808

1.3302186

1.253776

1.2903068

NA

NA

##

4

1.8037147

1.6929083

1.749211

1.9787633

NA

NA

##

5

5.8674102

5.9168840

5.901775

5.8329062

NA

NA

##

6

4.5594617

4.8377796

4.674925

4.8869875

NA

NA

Β 

Β 

Β 

Β 

Β 

Β 

Β 

image##y2017 y2018##1NANA##2NANA##3NANA##4NANA##5NANA##6NANA
Code book for data frame Emission See Homework problem 7.3.1 in section 7.3

  • The amount of sugar in a Krispy Kream glazed donut is 10 g. Many people feel that cereal is a healthier alternative for children over glazed donuts. Table #8.3.5 contains the amount of sugar in a sample of cereal that is geared towards children (breakfast cereal, 2019). Estimate the mean amount of sugar in children’s cereal at the 95% confidence level.

Table #8.3.5: Nutrition Amounts in Cereal

imageSugar <- read.csv( “https://krkozak.github.io/MAT160/cereal.csv”)head(Sugar)

Β 

##

Β 

namemanfage type

##

1

100%_BranNabisco adult cold

##

2

100%_Natural_BranQuaker_Oats adult cold

##

3

All-BranKelloggs adult cold

##

4

All-Bran_with_Extra_FiberKelloggs adult cold

##

5

Almond_Delight Ralston_Purina adult cold

##

6

Apple_Cinnamon_Cheerios General_Mills child cold

##

Β 

colories protein fat sodium fiber carb sugar shelf

##

1

70

4

1130 10.0 5.0

6

3

##

2

120

3

5152.0 8.0

8

3

##

3

70

4

12609.0 7.0

5

3

##

4

50

4

0140 14.0 8.0

0

3

##

5

110

2

22001.0 14.0

8

3

##

6

110

2

21801.5 10.5

10

1

##potassium vit weight serving

Β 

Β 

##

1

280

25

1

0.33

##

2

135

0

1

-1.00

##

3

320

25

1

0.33

##

4

330

25

1

0.50

##

5

-1

25

1

0.75

##

6

70

25

1

0.75

Code book for data frame Sugar See Homework problem 7.3.2 in section 7.3

A new data frame will need to be created of just cereal for children. To create that use the following command in R Studio

Table #8.3.6: Nutrition Amounts in Children’s Cereal

imageSugar_chidren<- Sugar%>%filter(age==”child”) head(Sugar_chidren)

Β 

##name manf age type ## 1 Apple_Cinnamon_Cheerios General_Mills child cold ## 2Apple_Jacks Kelloggs child cold

## 3Bran_Chex Ralston_Purina child cold

## 4 Cap’n’Crunch Quaker_Oats child cold

## 5Cheerios General_Mills child cold ## 6 Cinnamon_Toast_Crunch General_Mills child cold ## colories protein fat sodium fiber carb sugar shelf

## 1

110

2

2

180

1.5 10.5

10

1

## 2

110

2

0

125

1.0 11.0

14

2

## 3

90

2

1

200

4.0 15.0

6

1

## 4

120

1

2

220

0.0 12.0

12

2

## 5

110

6

2

290

2.0 17.0

1

1

## 6

120

1

3

210

0.0 13.0

9

2

image##1702510.75##2302511.00##31252510.67##4352510.75##51052511.25##6452510.75
## potassium vit weight serving

Β 

Β 

Β 

Β 

Β 

Β 

  • The FDA regulates that fish that is consumed is allowed to contain 1.0 mg/kg of mercury. In Florida, bass fish were collected in 53 different lakes to measure the health of the lakes. The data frame of measurements from Florida lakes is in table #8.3.7 (NISER 081107 ID Data, 2019). Calculate with 90% confidence the mean amount of mercury in fish in Florida lakes. Is there too much mercury in the fish in Florida?

image##pulse_beforepulse_afteryear##1707193##2807693##36812595##4706895##5928496

Table #8.3.7: Health of Florida lake Fish

imageMercury<- read.csv( “https://krkozak.github.io/MAT160/mercury.csv”)head(Mercury)

Β 

##

ID

lake

alkalinity

ph

calcium

chlorophyll

##

1 1

Alligator

5.9

6.1

3.0

0.7

##

2 2

Annie

3.5

5.1

1.9

3.2

##

3 3

Apopka

116.0

9.1

44.1

128.3

##

4 4

Blue_Cypress

39.4

6.9

16.4

3.5

##

5 5

Brick

2.5

4.6

2.9

1.8

##

6 6

Bryant

19.6

7.3

4.5

44.1

##mercury no.samples min max X3_yr_standmercury age_data

##

11.23

5

0.85 1.43

1.53

1

##

21.33

7

0.92 1.90

1.33

0

##

30.04

6

0.04 0.06

0.04

0

##

40.44

12

0.13 0.84

0.44

0

##

51.20

12

0.69 1.50

1.33

1

##

60.27

14

0.04 0.48

0.25

1

Code book for data frame Mercury See Homework problem 7.3.3 in section 7.3

  • The data frame Pulse (Table 8.3.8) contains various variables about a person including their pulse rates before the subject exercised and after the subject ran in place for one minute. Estimate the mean pulse rate of females who do drink alcohol with a 95% level of confidence?

Table #8.3.8: Pulse Rates Pulse Rates of people Before and After Exercise

imagePulse<-read.csv( “https://krkozak.github.io/MAT160/pulse.csv”)head(Pulse)

##height weight age gender smokes alcohol exercise ran

## 1

170

68

22

male

yes

yes moderate sat

## 2

182

75

26

male

yes

yes moderate sat

## 3

180

85

19

male

yes

yes moderate ran

## 4

182

85

20

male

yes

yes

low sat

## 5

167

70

22

male

yes

yes

low sat

## 6

178

86

21

male

yes

yes

low sat

Β 

Β 

## 6 76 80 98

Code book for data frame Pulse, see homework problem 3.2.5 in section 3.2

To create a new data frame with just females who drink alcohol use the following command, where the new name is Females: Table #8.3.9: Pulse Rates Pulse Rates of people Before and After Exercise

imageFemales<- Pulse%>%filter(gender==”female”, alcohol==”yes”)head(Females)

##height weight age gender smokes alcohol exercise ran

##

1

165

60

19

female

yes

yes

low

ran

##

2

163

47

23

female

yes

yes

low

ran

##

3

173

57

18

female

no

yes

moderate

sat

##

4

179

58

19

female

no

yes

moderate

ran

##

5

167

62

18

female

no

yes

high

ran

##

6

173

64

18

female

no

yes

low

sat

##

Β 

pulse_before

pulse_after

year

##

1

88

120

98

##

2

71

125

98

##

3

86

88

93

##

4

82

150

93

##

5

96

176

93

##

6

90

88

93

  • The economic dynamism is an index of productive growth in dollars. Eco- nomic data for many countries are in table #8.3.10 (SOCR Data 2008 World CountriesRankings, 2019).

image##10LowalAlbaniaSmallSouthern_Europe popS##21MiddledzAlgeriaMediumNorth_Africa popM##32MiddlearArgentinaMediumSouth_America popM##43HighauAustraliaMediumAustralia popM##54HighatAustriaSmallCentral_Europe popS##65LowazAzerbaijanSmallcentral_Asia popS##EDEduHIQOLPE OA Relig##134.0862 81.016471.0244 67.9240 58.6742 5739##225.8057 74.802766.1951 60.9347 32.6054 8595
Table #8.3.10: Economic Data for Countries

imageEconomics <- read.csv( “https://krkozak.github.io/MAT160/Economics_country.csv”)head(Economics)

##Id incGroup keyname popGroupregion key2

Β 

Β 

##

3

37.4511

69.8825

78.2683

68.1559

68.6647

46

66

##

4

71.4888

91.4802

95.1707

90.5729

90.9629

4

65

##

5

53.9431

90.4578

90.3415

87.5630

91.2073

18

20

##

6

53.6457

68.9880

58.9512

68.9572

40.0390

69

50

Code book for data frame Economics See Homework problem 7.3.5 in section 7.3

Create a data frame that contains only middle income countries. Find a 95% confidence interval for the mean econimic dynamism for middle income coun- tries. To create a new data frame with just middle income countries use the fol- lowing command, where the new name is Middle_economics: Table #8.3.11: Economic Data for Middle income Countries

imageMiddle_economics<- Economics%>%filter(incGroup==”Middle”) head(Middle_economics)

##Id incGroup keyname popGroupregion key2

##

1

1

Middle

dz

Algeria

Medium

North_Africa

popM

##

2

2

Middle

ar

Argentina

Medium

South_America

popM

##

3

7

Middle

by

Belarus

Small

central_Asia

popS

##

4

10

Middle

bw

Botswana

Small

Africa

popS

##

5

11

Middle

br

Brazil

Large

South_America

popL

##

6

12

Middle

bg

Bulgaria

Small

Southern_Europe

popS

##

Β 

Β 

ED

Edu

HI

QOL

PE OA Relig

Β 

##

1

25.8057

74.8027

66.1951

60.9347

32.6054

85

95

##

2

37.4511

69.8825

78.2683

68.1559

68.6647

46

66

##

3

51.9150

86.6155

66.1951

74.1467

34.0501

56

34

##

4

43.6952

73.4608

34.8049

50.0875

72.6833

80

80

##

5

47.8506

71.3735

71.0244

62.4238

67.4131

48

87

##

6

43.7178

82.2277

75.8537

73.1197

73.1686

38

50

  • Table #8.3.12 contains the percentage of woman receiving prenatal care in a sample of countries over several years. (births per woman), 2019). Estimate the average percentage of women receiving prenatal care in 2009 (p2009) with a 95% confidence interval?

image## 1AngolaAGOSub-Saharan Africa## 2ArmeniaARMEurope & Central Asia## 3BelizeBLZLatin America & Caribbean
Table #8.3.12: Data of Prenatal Care versus Health Expenditure

imageFert_prenatal<- read.csv( “https://krkozak.github.io/MAT160/fertility_prenatal.csv”)head(Fert_prenatal)

##Country.Name Country.CodeRegion

Β 

image## 4 Cote d’IvoireCIVSub-Saharan Africa## 5EthiopiaETHSub-Saharan Africa## 6GuineaGINSub-Saharan Africa
image##IncomeGroupf1960f1961f1962f1963f1964f1965##1Lowermiddleincome7.4787.5247.5637.5927.6117.619##2Uppermiddleincome4.7864.6704.5214.3454.1503.950##3Uppermiddleincome6.5006.4806.4606.4406.4206.400##4Lowermiddleincome7.6917.7207.7507.7817.8117.841##5Lowincome6.8806.8776.8756.8726.8676.864##6Lowincome6.1146.1276.1386.1476.1546.160

Β 

Β 

Β 

Β 

Β 

Β 

Β 

Β 

Β 

Β 

##

f1966

f1967

f1968

f1969

f1970

f1971

f1972

f1973

f1974

##

1

7.618

7.613

7.608

7.604

7.601

7.603

7.606

7.611

7.614

##

2

3.758

3.582

3.429

3.302

3.199

3.114

3.035

2.956

2.875

##

3

6.379

6.358

6.337

6.316

6.299

6.288

6.284

6.285

6.287

##

4

7.868

7.893

7.912

7.927

7.936

7.941

7.942

7.939

7.929

##

5

6.867

6.880

6.903

6.937

6.978

7.020

7.060

7.094

7.121

##

6

6.168

6.177

6.189

6.205

6.225

6.249

6.277

6.306

6.337

##

Β 

f1975

f1976

f1977

f1978

f1979

f1980

f1981

f1982

f1983

##

1

7.615

7.609

7.594

7.571

7.540

7.504

7.469

7.438

7.413

##

2

2.792

2.712

2.641

2.582

2.538

2.510

2.499

2.503

2.517

##

3

6.278

6.250

6.195

6.109

5.992

5.849

5.684

5.510

5.336

##

4

7.910

7.877

7.828

7.763

7.682

7.590

7.488

7.383

7.278

##

5

7.143

7.167

7.195

7.230

7.271

7.316

7.360

7.397

7.424

##

6

6.369

6.402

6.436

6.468

6.500

6.529

6.557

6.581

6.602

##

Β 

f1984

f1985

f1986

f1987

f1988

f1989

f1990

f1991

f1992

##

1

7.394

7.380

7.366

7.349

7.324

7.291

7.247

7.193

7.130

##

2

2.538

2.559

2.578

2.591

2.592

2.578

2.544

2.484

2.400

##

3

5.170

5.019

4.886

4.771

4.671

4.584

4.508

4.436

4.363

##

4

7.176

7.078

6.984

6.892

6.801

6.710

6.622

6.536

6.454

##

5

7.437

7.435

7.418

7.387

7.347

7.298

7.246

7.193

7.143

##

6

6.619

6.631

6.637

6.637

6.631

6.618

6.598

6.570

6.535

##

Β 

f1993

f1994

f1995

f1996

f1997

f1998

f1999

f2000

f2001

##

1

7.063

6.992

6.922

6.854

6.791

6.734

6.683

6.639

6.602

##

2

2.297

2.179

2.056

1.938

1.832

1.747

1.685

1.648

1.635

##

3

4.286

4.201

4.109

4.010

3.908

3.805

3.703

3.600

3.496

##

4

6.374

6.298

6.224

6.152

6.079

6.006

5.932

5.859

5.787

##

5

7.094

7.046

6.995

6.935

6.861

6.769

6.659

6.529

6.380

##

6

6.493

6.444

6.391

6.334

6.273

6.211

6.147

6.082

6.015

##

Β 

f2002

f2003

f2004

f2005

f2006

f2007

f2008

f2009

f2010

##

1

6.568

6.536

6.502

6.465

6.420

6.368

6.307

6.238

6.162

##

2

1.637

1.648

1.665

1.681

1.694

1.702

1.706

1.703

1.693

##

3

3.390

3.282

3.175

3.072

2.977

2.893

2.821

2.762

2.715

##

4

5.717

5.651

5.589

5.531

5.476

5.423

5.372

5.321

5.269

##

5

6.216

6.044

5.867

5.690

5.519

5.355

5.201

5.057

4.924

##

6

5.947

5.877

5.804

5.729

5.653

5.575

5.496

5.417

5.336

##

Β 

f2011

f2012

f2013

f2014

f2015

f2016

f2017

p1986

p1987

Β 

image## 1NANANANANANANANANA## 2NANANANANANANANANA## 3NANANA96NANANANANA## 4NANANANANANA83.2NANA## 5NANANANANANANANANA## 6NANANANA57.6NANANANA

##

1

6.082

6.000

5.920

5.841

5.766

5.694

5.623

NA

NA

##

2

1.680

1.664

1.648

1.634

1.622

1.612

1.604

NA

NA

##

3

2.676

2.642

2.610

2.578

2.544

2.510

2.475

NA

NA

##

4

5.216

5.160

5.101

5.039

4.976

4.911

4.846

NA

NA

##

5

4.798

4.677

4.556

4.437

4.317

4.198

4.081

NA

NA

##

6

5.256

5.175

5.094

5.014

4.934

4.855

4.777

NA

NA

##

Β 

p1988

p1989

p1990

p1991

p1992

p1993

p1994

p1995

p1996

Β 

Β 

Β 

Β 

Β 

Β 

##

p1997

p1998

p1999

p2000

p2001

p2002

p2003

p2004

p2005

##

1

NA

NA

NA

NA

65.6

NA

NA

NA

NA

##

2

82

NA

NA

92.4

NA

NA

NA

NA

93.0

##

3

NA

98

95.9

100.0

NA

98

NA

NA

94.0

##

4

NA

NA

84.3

87.6

NA

NA

NA

NA

87.3

##

5

NA

NA

NA

26.7

NA

NA

NA

NA

27.6

##

6

NA

NA

70.7

NA

NA

NA

84.3

NA

82.2

##

Β 

p2006

p2007

p2008

p2009

p2010

p2011

p2012

p2013

p2014

##

1

NA

79.8

NA

NA

NA

NA

NA

NA

NA

##

2

NA

NA

NA

NA

99.1

NA

NA

NA

NA

##

3

94.0

99.2

NA

NA

NA

96.2

NA

NA

NA

##

4

84.8

NA

NA

NA

NA

NA

90.6

NA

NA

##

5

NA

NA

NA

NA

NA

33.9

NA

NA

41.2

##

6

NA

88.4

NA

NA

NA

NA

85.2

NA

NA

##

p2015

p2016

p2017

p2018

e2000

e2001

e2002

##

1

NA

81.6

NA

NA

2.334435

5.483824

4.072288

##

2

NA

99.6

NA

NA

6.505224

6.536262

5.690812

##

3

97.2

97.2

NA

NA

3.942030

4.228792

3.864327

##

4

NA

93.2

NA

NA

5.672228

4.850694

4.476869

##

5

NA

62.4

NA

NA

4.365290

4.713670

4.705820

##

6

NA

84.3

NA

NA

3.697726

3.884610

4.384152

##

e2003

e2004

e2005

e2006

e2007

e2008

##

1

4.454100

4.757211

3.734836

3.366183

3.211438

3.495036

##

2

5.610725

8.227844

7.034880

5.588461

5.445144

4.346749

##

3

4.260178

4.091610

4.216728

4.163924

4.568384

4.646109

##

4

4.645306

5.213588

5.353556

5.808850

6.259154

6.121604

##

5

4.885341

4.304562

4.100981

4.226696

4.801925

4.280639

##

6

3.651081

3.365547

2.949490

2.960601

3.013074

2.762090

##

Β 

e2009

e2010

e2011

e2012

e2013

e2014

##

1

3.578677

2.736684

2.840603

2.692890

2.990929

2.798719

##

2

4.689046

5.264181

3.777260

6.711859

8.269840

10.178299

##

3

5.311070

5.764874

5.575126

5.322589

5.727331

5.652458

##

4

6.223329

6.146566

5.978840

6.019660

5.074942

5.043462

Β 

Β 

## 5

4.412473 5.466372 4.468978 4.539596 4.075065 4.033651

## 6

2.936868 3.067742 3.789550 3.503983 3.461137 4.780977

##

e2015e2016

## 1

2.950431 2.877825

## 2

10.117628 9.927321

## 3

5.884248 6.121374

## 4

5.262711 4.403621

## 5

3.975932 3.974016

## 6

5.827122 5.478273

Code book for Data frame Fert_prenatal See Problem 2.3.4 in Section

2.3 homework

  • Maintaining your balance may get harder as you grow older. A study was conducted to see how steady the elderly is on their feet. They had the subjects stand on a force platform and have them react to a noise. The force platform then measured how much they swayed forward and backward, and the data is in table #8.3.13 (Maintaining Balance while Concentrating, 2019). Find the mean forward/backward sway of elderly person? Use a 95% confidence level. Follow the filtering methods in other homework problems to create a data frame for only Elderly.

Table #8.3.13: Sway (in mm) of Elderly Subjects

imageSway <- read.csv( “https://krkozak.github.io/MAT160/sway.csv”)head(Sway)

##age fbsway sidesway

## 1 Elderly

19

14

## 2 Elderly

30

41

## 3 Elderly

20

18

## 4 Elderly

19

11

## 5 Elderly

29

16

## 6 Elderly

25

24

Code book for data frame Sway See Homework problem 7.3.7 in section 7.3

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Β 

Data Sources:

Australian Human Rights Commission, (1996). Indigenous deaths in custody 1989 – 1996. Retrieved from website: http://www.humanrights.gov.au/ publications/indigenous-deaths-custody

CDC features new data on autism spectrum disorders. (2013, November 26). Retrieved from http://www.cdc.gov/features/countingautism/

Center for Disease Control and Prevention, Prevalence of Autism Spectrum

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Β 

Disorders – Autism and Developmental Disabilities Monitoring Network. (2008). Autism and developmental disabilities monitoring network-2012. Retrieved from website: http://www.cdc.gov/ncbddd/autism/documents/ADDM-2012- Community-Report.pdf

Federal Trade Commission, (2008). Consumer fraud and identity theft complaint data: January-December 2007. Retrieved from website: http://www.ftc.gov/ opa/2008/02/fraud.pdf

Sanchez, Y. W. (2016, October 20). Poll: Arizona voters still favor legal- izing marijuana.Retrieved from https://www.azcentral.com/story/news/ politics/elections/2016/10/20/poll-arizona-marijuana-legalization-proposition- 205/92417690/

http://apps.who.int/gho/athena/data/download.xsl?format=xml&target= GHO/WHOSIS_000001&profile=excel&filter=COUNTRY:;SEX:;REGION:EUR

CO2 emissions (metric tons per capita). (n.d.). Retrieved July 18, 2019, from https://data.worldbank.org/indicator/EN.ATM.CO2E.PC

(n.d.). Retrieved July 18, 2019, from https://www.idvbook.com/teaching- aid/data-sets/the-breakfast-cereal-data-set/ The Best Kids’ Cereal. (n.d.). Retrieved July 18, 2019, from https://www.ranker.com/list/best-kids- cereal/ranker-food

Lange TL, Royals HE, Connor LL (1993) Influence of water chemistry on mer- cury concentration in largemouth bass from Florida lakes. Trans Am Fish Soc 122:74-84. Michael K. Saiki, Darell G. Slotton, Thomas W. May, Shaun M. Ay- ers, and Charles N. Alpers (2000) Summary of Total Mercury Concentrations in Fillets of Selected Sport Fishes Collected during 2000–2003 from Lake Natoma, Sacramento County, California (Raw data is included in appendix), U.S. Geo- logical Survey Data Series 103, 1-21. NISER 081107 ID Data. (n.d.). Retrieved July 18, 2019, from http://wiki.stat.ucla.edu/socr/index.php/NISER_081107_ ID_Data

SOCR Data 2008 World CountriesRankings.(n.d.).Retrieved July 19, 2019,fromhttp://wiki.stat.ucla.edu/socr/index.php/SOCR_Data_2008_ World_CountriesRankings#SOCR_Data_-_Ranking_of_the_top_100_ Countries_based_on_Political.2C_Economic.2C_Health.2C_and_Quality-

of-Life_Factors

Maintaining Balance while Concentrating. (n.d.). Retrieved July 19, 2019, from http://www.statsci.org/data/general/balaconc.html

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Chapter 9

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License

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