/*! 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 16 Lying online Many teens have pos... [FREE SOLUTION] | 91影视

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Lying online Many teens have posted profiles on sites such as Facebook and MySpace. A sample survey asked random samples of teens with online profiles if they included false information in their profiles. Of 170 younger teens (ages 12 to 14) polled, 117 said 鈥淵es.鈥 Of 317 older teens (ages 15 to 17) polled, 152 said 鈥淵es.鈥6 A 95% confidence interval for the difference in the population proportions (younger teens 鈥 older teens) is 0.120 to 0.297. Interpret the confidence interval and the confidence level.

Short Answer

Expert verified
The difference in proportions suggests younger teens lie more, with 95% confidence, by about 12% to 29.7% compared to older teens.

Step by step solution

01

Identify Parameters

Define the parameters for the two groups. Let p_1 denote the proportion of younger teens (ages 12 to 14) who included false information in their profiles. Let p_2 denote the proportion of older teens (ages 15 to 17) who included false information.
02

State the Difference

The problem asks for the confidence interval for the difference between the two proportions, p_1 - p_2, which is given as 0.120 to 0.297.
03

Confidence Interval Interpretation

The confidence interval of 0.120 to 0.297 implies that we are 95% confident that the proportion of younger teens who included false information is between 12% and 29.7% higher than the proportion of older teens who did the same.
04

Confidence Level Explanation

A 95% confidence level means that if we were to take many samples and create confidence intervals from each of them, about 95% of these intervals would contain the true difference in population proportions between younger and older teens.

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Key Concepts

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

Confidence Interval
A confidence interval is a range of values we use to estimate a population parameter. In our case, it is used to estimate the difference in proportions of teens providing false information online. The confidence interval provides a range likely to contain the true value of this difference. For example, a 95% confidence interval from 0.120 to 0.297 suggests that we are 95% sure the true difference in online misinformation between the two teen groups lies somewhere between 12% and 29.7%.

Confidence intervals are vital in statistics, as they give an estimation of the uncertainty around a point estimate, like the difference in proportions. By calculating and interpreting them correctly, we gain insights into the variability and reliability of the data collected from surveys.
Population Proportion
In statistics, population proportion refers to the fraction of the total population that exhibits a certain characteristic. Here, it represents the teens who admit to including false information in their online profiles. For younger teens (ages 12 to 14), the population proportion (\( p_1 \)) is reported as those polled who admitted to lying online. Similarly, for older teens (ages 15 to 17), the population proportion (\( p_2 \)) is derived in the same way.

Understanding population proportions and how they vary between different groups is crucial for analyzing social behaviors, such as in our teen behavior study. By comparing these proportions between various groups, it's possible to uncover meaningful patterns and trends.
Survey Sampling
Survey sampling is a method used to draw conclusions about a population by studying a subset, or sample, of that population. In the exercise, we think about teens on social media. The researcher sampled younger and older teens separately to gather data on online behaviors.

Essentially, good sampling ensures that the data collected is representative of the entire population. If done randomly and without bias, it gives valid insights that can be extended to the population with a level of confidence. It's important to minimize biases in sampling techniques, as this strengthens the accuracy and reliability of the study's findings.
Teen Behavior Online
Teen behavior online is an interesting and relevant subject as it reflects broader social tendencies. In this context, the survey reveals the tendency of teens to present false information, a behavior that spans across both younger and older age groups. The inquiry into whether younger teens lie more often online than their older peers is particularly insightful.

Understanding teen behavior online helps parents, educators, and policymakers guide youth in responsible internet use. This includes making informed decisions about privacy and truthfulness. Surveys, like the one examined, provide valuable data that can lead to initiatives promoting safer, more honest online environments for teenagers.

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