Chapter 6 – Estimation Procedures
45 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the value of Z for a 99% confidence interval?

  • 3.29
  • 2.58 (correct)
  • 1.64
  • 1.96
  • What is the formula to calculate the required sample size for a desired level of precision?

  • $n = Z \times \sigma + ME$
  • $n = \frac{Z^2 \times \sigma^2}{ME^2}$ (correct)
  • $n = \frac{Z \times \sigma}{ME}$
  • $n = \frac{ME^2}{Z^2 \times \sigma^2}$
  • How many older adults does the gerontologist need to sample to be 99% confident within a margin of error of $1,000?

  • 200
  • 167 (correct)
  • 250
  • 100
  • If the margin of error (ME) was increased to $1,500, what would be the effect on the required sample size?

    <p>Sample size would decrease (B)</p> Signup and view all the answers

    What does the term σ represent in the sample size formula?

    <p>Population standard deviation (D)</p> Signup and view all the answers

    What does efficiency in the context of an estimator primarily relate to?

    <p>The clustering of the sampling distribution about its mean (B)</p> Signup and view all the answers

    How is the standard error of the mean calculated?

    <p>Population standard deviation divided by the square root of sample size (C)</p> Signup and view all the answers

    Which sample size would yield a lower standard deviation of the sampling distribution?

    <p>Sample size of 1,000 (C)</p> Signup and view all the answers

    If the population standard deviation is $5,000 and the sample size is 100, what is the standard deviation of the sampling distribution?

    <p>$500 (B)</p> Signup and view all the answers

    What effect does increasing the sample size have on the efficiency of the estimator?

    <p>It increases clustering (D)</p> Signup and view all the answers

    What is the standard deviation of all possible sample means for a sample of size 1,000 with a population standard deviation of $5,000?

    <p>$158.13 (A)</p> Signup and view all the answers

    In terms of bias, how do both samples (n=100 and n=1,000) compare when sampling the same population?

    <p>Both samples are unbiased estimators (B)</p> Signup and view all the answers

    What is the standard deviation of the sampling distribution for a sample size of 100 when the population standard deviation is $5,000?

    <p>$500.00 (B)</p> Signup and view all the answers

    What is the sample proportion of respondents who are 'very happy' in the United States?

    <p>0.360 (D)</p> Signup and view all the answers

    Which country has the highest number of respondents reporting they are 'very happy'?

    <p>United States (B)</p> Signup and view all the answers

    At the 95% confidence level, what formula is typically used to estimate a confidence interval for a sample proportion?

    <p>p ± Z * sqrt((p*(1-p))/n) (A)</p> Signup and view all the answers

    If 35 out of 150 respondents are 'extremely' interested in clubs, what is the estimated sample proportion?

    <p>0.23 (C)</p> Signup and view all the answers

    What is the critical Z-value used when constructing a 95% confidence interval?

    <p>1.96 (C)</p> Signup and view all the answers

    What is the average (X̄) occupational prestige score reported in the survey?

    <p>43.87 (C)</p> Signup and view all the answers

    Which value represents the standard deviation for the respondents' average daily television watching?

    <p>2.20 (A)</p> Signup and view all the answers

    What is the correct interpretation of a confidence interval?

    <p>It provides a range of values likely containing the population parameter. (D)</p> Signup and view all the answers

    What does the mean number of cigarettes smoked per day for daily smokers in Canada represent?

    <p>An estimate of cigarette consumption for daily smokers. (C)</p> Signup and view all the answers

    What is the calculated 95% confidence interval for the mean number of cigarettes smoked per day?

    <p>Between 13.76 and 16.19. (D)</p> Signup and view all the answers

    How can SPSS be used to calculate sample proportions?

    <p>By using the Frequencies command to determine valid frequencies. (C)</p> Signup and view all the answers

    What percentage of respondents reported having a seasonal flu shot in their lifetime?

    <p>60.5% (D)</p> Signup and view all the answers

    What is necessary to compute the confidence interval for a sample proportion?

    <p>Sample statistics and sample proportions. (D)</p> Signup and view all the answers

    Which command in SPSS is NOT relevant for calculating sample proportions?

    <p>Correlation (B)</p> Signup and view all the answers

    What proportion corresponds to a percentage of 39.5%?

    <p>0.3950 (A), 0.395 (C)</p> Signup and view all the answers

    What does Pu in the confidence interval formula represent?

    <p>The sample proportion for the studied variable. (B)</p> Signup and view all the answers

    What key methodological information is required in published election period poll results?

    <p>The date on which the poll was conducted (C)</p> Signup and view all the answers

    What is one significant benefit of the growth in opinion polling for social sciences?

    <p>Greater availability of nationally representative databases (D)</p> Signup and view all the answers

    How does the General Social Survey (GSS) enhance research credibility?

    <p>By offering high-quality data for testing theories (D)</p> Signup and view all the answers

    Since when has Statistics Canada conducted the General Social Survey (GSS)?

    <p>1985 (A)</p> Signup and view all the answers

    What type of design is used to select the GSS sample?

    <p>Probability design based on EPSEM (C)</p> Signup and view all the answers

    What does the GSS enable researchers to do regarding public opinion?

    <p>Assess trends in public opinion over time (D)</p> Signup and view all the answers

    Which type of record does the GSS provide due to its longitudinal nature?

    <p>Longitudinal record of sentiment and opinion (A)</p> Signup and view all the answers

    What is a characteristic of the sample size in the GSS?

    <p>It is in the thousands providing high precision (A)</p> Signup and view all the answers

    What percentage of the sample agreed that marijuana should be legalized?

    <p>375 (D)</p> Signup and view all the answers

    How many respondents attended a religious service at least once in the past month?

    <p>1023 (B)</p> Signup and view all the answers

    What is the sample size used to construct confidence intervals for the population mean with a sample mean of 100 and standard deviation of 100?

    <p>500 (C)</p> Signup and view all the answers

    What effect does increasing the confidence level have on the width of the confidence interval?

    <p>It increases the width. (D)</p> Signup and view all the answers

    What was the sample proportion used throughout for the three sample sizes in constructing the confidence interval?

    <p>0.40 (A)</p> Signup and view all the answers

    At what confidence level is the prediction about candidate A's margin of victory being assessed?

    <p>99% (A)</p> Signup and view all the answers

    What is the required percentage of the vote for a candidate to be considered a winner in a two-candidate race?

    <p>51% (B)</p> Signup and view all the answers

    What was the sample size used in the survey that found 51% of respondents preferred candidate A for mayor?

    <p>578 (C)</p> Signup and view all the answers

    Flashcards

    Efficiency of an estimator

    How clustered the sampling distribution is around its mean.

    Higher Efficiency

    Smaller standard deviation of the sampling distribution means higher efficiency.

    Standard Error of the Mean

    Standard deviation of the sampling distribution of sample means.

    Relationship of Standard Error of the Mean and Sample Size

    Standard error of the mean is inversely proportional to the square root of the sample size.

    Signup and view all the flashcards

    Increasing Sample Size

    Increases estimator efficiency by decreasing the standard deviation of the sampling distribution.

    Signup and view all the flashcards

    Unbiased Estimator

    Expected value of the estimator equals the population parameter.

    Signup and view all the flashcards

    Example of Efficiency

    Larger sample size (1000) is more efficient than smaller sample size (100) even if sample means are the same, because it has a smaller standard deviation of sampling distribution.

    Signup and view all the flashcards

    Sampling Distribution

    Distribution of all possible values of a statistic that one might get if you were to acquire many samples from a particular population.

    Signup and view all the flashcards

    Sample Size Formula

    A formula used to calculate the required sample size for a desired level of precision in a simple random sample.

    Signup and view all the flashcards

    Margin of Error (ME)

    The maximum allowable difference between the sample mean and the population mean.

    Signup and view all the flashcards

    Z-Score & Confidence Level

    A Z-score represents the number of standard deviations a sample mean is from the population mean. It's used to determine the confidence level (probability) of the estimate.

    Signup and view all the flashcards

    Population Standard Deviation (σ)

    A measure of the spread (variation) of data in the entire population.

    Signup and view all the flashcards

    How does sample size affect precision?

    Larger sample sizes lead to higher precision (smaller margin of error) because the sample mean is more likely to be closer to the population mean.

    Signup and view all the flashcards

    Public Opinion Surveys

    Systematic studies that measure public attitudes, beliefs, and behaviors on various topics.

    Signup and view all the flashcards

    Nationally Representative Databases

    Datasets that accurately reflect the characteristics of a nation's population, allowing researchers to study trends and patterns.

    Signup and view all the flashcards

    General Social Survey (GSS)

    An annual survey conducted by Statistics Canada that collects data on various social and demographic aspects of Canadians.

    Signup and view all the flashcards

    Probability Design

    A sampling method that ensures every member of the population has a known chance of being selected for the survey.

    Signup and view all the flashcards

    EPSEM (Equal Probability of Selection Method)

    A sampling technique where every individual in the population has an equal chance of being included in the sample.

    Signup and view all the flashcards

    Tracking National Trends

    Analyzing data collected over time to identify changes and patterns in public opinion, behaviors, or social phenomena.

    Signup and view all the flashcards

    Longitudinal Record

    A dataset that tracks changes in the same variables over time, providing insights into how things evolve.

    Signup and view all the flashcards

    Assessing Trends in Criminal Victimization

    Analyzing survey data to understand how rates of victimization change over time, helping to identify patterns and potential solutions.

    Signup and view all the flashcards

    Confidence Level

    The probability that a confidence interval will contain the true population parameter.

    Signup and view all the flashcards

    Confidence Interval (CI)

    A range of values that is likely to contain the true population parameter.

    Signup and view all the flashcards

    How does Sample Size affect Confidence Interval?

    Larger sample sizes lead to narrower confidence intervals, indicating more precise estimates.

    Signup and view all the flashcards

    Estimating Population Proportion

    Calculating a range of values that is likely to contain the true population proportion based on sample data.

    Signup and view all the flashcards

    Construct a Confidence Interval

    The process of creating a range of values that is likely to contain the true population parameter.

    Signup and view all the flashcards

    Interpreting Confidence Intervals

    Determining the probability that the true population parameter lies within the calculated range.

    Signup and view all the flashcards

    Sample Proportion (Ps)

    The proportion of successes in a sample.

    Signup and view all the flashcards

    Confidence Interval

    A range of values that is likely to contain the true population parameter with a certain level of confidence.

    Signup and view all the flashcards

    Population Proportion (π)

    The proportion of a specific characteristic in the entire population.

    Signup and view all the flashcards

    Margin of Error

    The maximum allowable difference between the sample proportion and the population proportion.

    Signup and view all the flashcards

    Formula for Confidence Interval

    The formula used to calculate the confidence interval for a sample proportion.

    Signup and view all the flashcards

    Calculating Sample Proportion

    To calculate the sample proportion, divide the number of observations with the characteristic by the total number of observations in the sample.

    Signup and view all the flashcards

    Sample Proportion

    The proportion of a sample that possesses a certain characteristic, expressed as a decimal.

    Signup and view all the flashcards

    How to Calculate Sample Proportion

    Divide the number of individuals with the characteristic by the total sample size.

    Signup and view all the flashcards

    How to Interpret Confidence Interval

    The confidence interval provides a range of values within which the population parameter is likely to fall.

    Signup and view all the flashcards

    How Sample Size Affects Confidence Interval

    Larger sample sizes lead to narrower confidence intervals, providing more precise estimates.

    Signup and view all the flashcards

    What is Margin of Error?

    The maximum allowable difference between the sample statistic and the true population parameter.

    Signup and view all the flashcards

    Study Notes

    Estimation Procedures

    • Estimation procedures in inferential statistics aim to estimate population values from sample statistics.
    • Point estimates use a single sample statistic to estimate a population value.
    • Confidence intervals give a range of values (an interval) instead of a single point, providing a more comprehensive estimate.

    Bias and Efficiency

    • Estimators are selected based on bias and efficiency.
    • An unbiased estimator has a sampling distribution mean equal to the population value.
    • Sample means and proportions are typically unbiased.
    • Efficiency refers to clustering of the sampling distribution around its mean; a more clustered distribution indicates higher efficiency.
    • Smaller standard deviations of sampling distributions correspond to higher efficiency.
    • Larger sample sizes lead to more efficient estimates.

    Estimation Procedures: Introduction

    • Constructing a point estimate involves drawing a sample, calculating either a proportion or mean, and using that statistic to estimate the population parameter.
    • Larger samples produce more accurate point estimates.
    • Interval estimates, unlike point estimates, provide a range of values, rather than a single value.

    Interval Estimation Procedures for Sample Means (σ Known)

    • A confidence interval based on sample means utilizes a formula that accounts for the known population standard deviation.
    • The formula accounts for the sample mean and a relevant Z-score.

    Interval Estimation Procedures for Sample Means (σ Unknown)

    • Sample standard deviation is used as a substitute for the population standard deviation when it is unknown.
    • The formula adapted to the student's t distribution.
    • Sample size, greater than 100, can be assumed for a large sample.

    Interval Estimation Procedures for Sample Proportions (Large Samples)

    • Estimation procedures for sample proportions are similar to those for sample means.
    • The major difference is the use of a different sampling distribution due to the different statistic.
    • The Central Limit Theorem allows for the assumption of a normal distribution when nP and n(1-P) are 15 or larger.

    Graphing a Confidence Interval of a Sample Mean

    • Confidence intervals for sample means are graphically depicted using error bars, where the error bar spans the confidence interval.

    Determining Sample Size

    • Sample size needed to attain a desired confidence interval is determined before conducting a study.
    • Rearranging the formulas can be used to determine the sample size needed for various confidence interval estimates.

    Interpreting Statistics: Predicting the Election of the Government of Canada

    • Statistical methods for estimating population parameters are used in many ways.
    • Statistical techniques are applied to predict elections and estimate political sentiment.
    • Confidence intervals are used to estimate population values which provide a range of possible values, often expressed as percentages.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Description

    Test your knowledge on sample size calculations for a 99% confidence interval. This quiz covers key concepts such as the Z value, margin of error, and the significance of σ in sample size formulas. Perfect for students studying statistics or research methodology.

    More Like This

    Power & Sample Size PREP
    8 questions

    Power & Sample Size PREP

    WorldFamousZombie1045 avatar
    WorldFamousZombie1045
    Use Quizgecko on...
    Browser
    Browser