/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 55 The paper "The Curious Promiscui... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

The paper "The Curious Promiscuity of Queen Honey Bees (Apis mellifera): Evolutionary and Behavioral Mechanisms" (Annals of Zoology Fennici [2001]:255- 265) describes a study of the mating behavior of queen honeybees. The following quote is from the paper: Queens flew for an average of \(24.2 \pm 9.21\) minutes on their mating flights, which is consistent with previous findings. On those flights, queens effectively mated with \(4.6 \pm 3.47\) males (mean \(\pm \mathrm{SD})\). a. The intervals reported in the quote from the paper were based on data from the mating flights of \(n=\) 30 queen honeybees. One of the two intervals reported is stated to be a confidence interval for a population mean. Which interval is this? Justify your choice. b. Use the given information to construct a \(95 \%\) confidence interval for the mean number of partners on a mating flight for queen honeybees. For purposes of this exercise, assume that it is reasonable to consider these 30 queen honeybees as representative of the population of queen honeybees.

Short Answer

Expert verified
The interval \(4.6 \pm 3.47\) represents the confidence interval for the population mean. The 95% confidence interval for the mean number of partners on a mating flight for queen honeybees is approximately from 3.36 to 5.84.

Step by step solution

01

Identify the Confidence Interval

A confidence interval is an estimated range of values which is likely to include a population parameter. From the given information, it is clear that the intervals \(24.2 \pm 9.21\) and \(4.6 \pm 3.47\) are referring to the flight time and number of mates of the queen honeybees respectively. Given that they both appear to follow a normal distribution, either could be the confidence interval. However, the exercise's later part implicitly reveals that the mating number interval \(4.6 \pm 3.47\) is the confidence interval as we are asked to calculate a confidence interval for the mean number of mates.
02

Confidence Interval Formula

The formula for constructing a confidence interval is: \( \text{Confidence Interval} = \text{Sample mean} \pm (\text{Critical value} * \frac{\text{Standard Deviation}}{\sqrt{n}})\) where n is the sample size, and the Critical value for a 95% confidence level (with infinite degrees of freedom) is approximately 1.96 map.
03

Calculation of Confidence Interval

We have all the required values for the formula: Sample mean = 4.6, Standard Deviation = 3.47, and n=30. Substituting these, we get: Confidence Interval = \(4.6 \pm (1.96 * \frac{3.47}{\sqrt{30}})\). After calculating, we find the Confidence Interval = \(4.6 \pm 1.24\). Hence, the 95% confidence interval is from approximately 3.36 to 5.84.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Confidence Interval
A confidence interval is a way of expressing uncertainty in a measurement. When we talk about a sample (such as queen honeybees' mating flights), we use confidence intervals to estimate the range within which we expect the true population parameter (like the average number of mates) to fall. This concept helps us understand not just what the value might be, but also how much we can trust this estimate.
In general, a confidence interval is calculated by taking the sample mean and adding and subtracting the margin of error. The formula is:
  • \( ext{Confidence Interval} = ext{Sample mean} \pm ( ext{Critical value} * \frac{\text{Standard Deviation}}{\sqrt{n}})\)
where:
  • Sample mean is the average calculated from the sample data,
  • Critical value is determined based on the confidence level (e.g., 1.96 for 95% confidence),
  • Standard deviation describes how spread out the numbers are,
  • \(n\) is the number of observations in the sample.
Understanding this helps us measure of how likely the sample results represent the entire population. It's like saying, "We’re 95% sure the true average falls between this range."
Population Mean
The population mean is the average of a set of values in the entire population. This is different from a sample mean, which is an average calculated from a smaller group taken from that population. In studies like the one on queen honeybees, researchers often use sample means because measuring an entire population is unfeasible.
The importance of the population mean lies in its representation of the true central tendency of the data set. It is what researchers are often trying to estimate when they gather sample data. In practical terms, if we look at the queen honeybee study, the 4.6 mates figure is the sample mean which serves as an estimate for the population mean.
This concept is deeply tied to how we understand and interpret the results of research studies. Estimating the population mean allows researchers to make educated guesses about the behaviors or characteristics of the entire group, which in this case, would be how queen honeybees usually behave during mating flights. Understanding the difference between sample and population mean is crucial to understanding statistical analysis.
Normal Distribution
Normal distribution, often called a bell curve due to its shape, is a statistical phenomenon where data tends to cluster around a central value. This pattern is crucial for calculating many statistical measures, including confidence intervals.
In a normally distributed dataset, most values fall near the mean, and the probabilities for values are symmetric around this mean. The further away a value is from the mean, the less likely it is.
Key features of a normal distribution include:
  • Symmetry around the mean with no skewness,
  • Mean, median, and mode coincide,
  • 68% of data falls within one standard deviation from the mean, 95% within two, and 99.7% within three standard deviations.
In the context of the queen honeybee study, researchers assumed the data followed a normal distribution. This allows for reliable confidence interval calculations because the statistical properties of the normal distribution permit the use of specific formulas and critical values (like 1.96 for 95% confidence) for accurate estimation.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Based on a representative sample of 511 U.S. teenagers age 12 to 17 , International Communications Research estimated that the proportion of teens who support keeping the legal drinking age at 21 is \(\hat{p}=0.64\) \((64 \%)\). The press release titled "Majority of Teens (Still) Favor the Legal Drinking Age" (www.icrsurvey.com. January 21, 2009) also reported a margin of error of \(0.04(4 \%)\) for this estimate. Show how the reported value for the margin of error was computed.

Fat content (in grams) for seven randomly selected hot dogs that were rated as very good by Consumer Reports (www.consumerreports.org) is shown below. Is it reasonable to use this data and the \(t\) confidence interval of this section to construct a confidence interval for the mean fat content of hot dogs rated as very good by Consumer Reports? Explain why or why not. \(\begin{array}{lllllll}14 & 15 & 11 & 10 & 6 & 15 & 16\end{array}\)

In the article "Fluoridation Brushed Off by Utah" (Associated Press, August 24, 1998 ), it was reported that a small but vocal minority in Utah has been successful in keeping fluoride out of Utah water supplies despite evidence that fluoridation reduces tooth decay and despite the fact that a clear majority of Utah residents favor fluoridation. To support this statement, the article included the result of a survey of Utah residents that found \(65 \%\) to be in favor of fluoridation. Suppose that this result was based on a random sample of 150 Utah residents. Construct and interpret a \(90 \%\) confidence interval for \(p\), the true proportion of Utah residents who favor fluoridation. Is this interval consistent with the statement that fluoridation is favored by a clear majority of residents?

The article "Hospitals Dispute Medtronic Data on Wires" (The Wall Street journal. February 4,2010 ) describes several studies of the failure rate of defibrillators used in the treatment of heart problems. In one study conducted by the Mayo Clinic, it was reported that failures were experienced within the first 2 years by 18 of 89 patients under 50 years old and 13 of 362 patients age 50 and older who received a particular type of defibrillator. Assume it is reasonable to regard these two samples as representative of patients in the two age groups who receive this type of defibrillator. a. Construct and interpret a \(95 \%\) confidence interval for the proportion of patients under 50 years old who experience a failure within the first 2 years after receiving this type of defibrillator. b. Construct and interpret a \(99 \%\) confidence interval for the proportion of patients age 50 and older who experience a failure within the first 2 years after receiving this type of defibrillator. c. Suppose that the researchers wanted to estimate the proportion of patients under 50 years old who experience a failure within the first 2 years after receiving this type of defibrillator to within \(.03\) with \(95 \%\) confidence. How large a sample should be used? Use the results of the study as a preliminary estimate of the population proportion.

The article "The Association Between Television Viewing and Irregular Sleep Schedules Among Children Less Than 3 Years of Age" (Pediatrics [2005]: \(851-856\) ) reported the accompanying \(95 \%\) confidence intervals for average TV viewing time (in hours per day) for three different age groups. $$\begin{array}{lc} \text { Age Group } & 95 \% \text { Confidence Interval } \\ \hline \text { Less than } 12 \text { months } & (0.8,1.0) \\ 12 \text { to } 23 \text { months } & (1.4,1.8) \\ 24 \text { to } 35 \text { months } & (2.1,2.5) \\ \hline \end{array}$$ a. Suppose that the sample sizes for each of the three age group samples were equal. Based on the given confidence intervals, which of the age group samples had the greatest variability in TV viewing time? Explain your choice. b. Now suppose that the sample standard deviations for the three age group samples were equal, but that the three sample sizes might have been different. Which of the three age-group samples had the largest sample size? Explain your choice. c. The interval \((.768,1.032)\) is either a \(90 \%\) confidence interval or a \(99 \%\) confidence interval for the mean TV viewing time computed using the sample data for children less than 12 months old. Is the confidence level for this interval \(90 \%\) or \(99 \%\) ? Explain your choice.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.