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1. Intro to Stats and Collecting Data(0)

Intro to Stats
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Levels of Measurement
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Intro to Collecting Data
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Sampling Methods
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2. Describing Data with Tables and Graphs(0)

Visualizing Qualitative vs. Quantitative Data
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Frequency Distributions
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Histograms
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Bar Graphs and Pareto Charts
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Pie Charts
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Frequency Polygons
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Dot Plots
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Stemplots (Stem-and-Leaf Plots)
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Time-Series Graph
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3. Describing Data Numerically(0)

Mean
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Median
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Mode
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Standard Deviation
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Interpreting Standard Deviation
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Percentiles & Quartiles
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Boxplots
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4. Probability(0)

Basic Concepts of Probability
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Complements
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Addition Rule
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Multiplication Rule: Independent Events
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Introduction to Contingency Tables
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Multiplication Rule: Dependent Events
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Bayes' Theorem
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Fundamental Counting Principle
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Counting
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5. Binomial Distribution & Discrete Random Variables(0)

Discrete Random Variables
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Binomial Distribution
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Poisson Distribution
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Hypergeometric Distribution
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6. Normal Distribution and Continuous Random Variables(0)

Uniform Distribution
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Standard Normal Distribution
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Non-Standard Normal Distribution
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7. Sampling Distributions & Confidence Intervals: Mean(0)

Sampling Distribution of the Sample Mean and Central Limit Theorem
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Introduction to Confidence Intervals
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Confidence Intervals for Population Mean
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Determining the Minimum Sample Size Required
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8. Sampling Distributions & Confidence Intervals: Proportion(0)

Sampling Distribution of Sample Proportion
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Confidence Intervals for Population Proportion
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Chi Square Distribution
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Confidence Intervals for Population Variance
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9. Hypothesis Testing for One Sample(0)

Steps in Hypothesis Testing
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Performing Hypothesis Tests: Means
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Performing Hypothesis Tests: Proportions
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Performing Hypothesis Tests: Variance
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Critical Values and Rejection Regions
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Link Between Confidence Intervals and Hypothesis Testing
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Type I & Type II Errors
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10. Hypothesis Testing for Two Samples(0)

Two Proportions
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Two Means - Unknown, Unequal Variance
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Two Means - Unknown, Equal Variance
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Two Means - Known Variance
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Two Means - Matched Pairs (Dependent Samples)
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Two Variances and F Distribution
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11. Correlation(0)

Scatterplots & Intro to Correlation
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Correlation Coefficient
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12. Regression(0)

Linear Regression & Least Squares Method
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Residuals
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Coefficient of Determination
(0)

Inferences for Slope
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Prediction Intervals
(0)

Quadratic Regression
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13. Chi-Square Tests & Goodness of Fit(0)

Goodness of Fit Test
(0)

Contingency Tables
(0)

Independence Tests
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Homogeneity Tests
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14. ANOVA(0)

Introduction to ANOVA
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Multiple Comparisons: Tukey Test
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Multiple Comparisons: Tukey-Kramer Test
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Multiple Comparisons: Bonferoni Test
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Two-Way ANOVA
(0)

8. Sampling Distributions & Confidence Intervals: Proportion

Confidence Intervals for Population Proportion

8. Sampling Distributions & Confidence Intervals: Proportion

Confidence Intervals for Population Proportion: 동영상 및 연습문제

비디오 강의 실무 워크시트

130 문제점

문제 1객관식

Suppose the weights of newborn babies in a certain city are normally distributed with a mean of $3.4 kg$ and a standard deviation of $0.5 kg$ . If a sample of $16$ newborns is chosen at random and their mean weight is computed, what is the mean of all such sample means?

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문제 2객관식

A company surveyed $250$ employees and found that $85$ of them prefer to work remotely. Construct a $95 percent sign$ confidence interval for the proportion of all employees who prefer to work remotely.

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문제 3객관식

The proportion of purple jellybeans in a sample yields a confidence interval of $0.205 is less than p is less than 0.295$ . Express this confidence interval in the form $\hat{p} \pm E$ .

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문제 4객관식

In a poll of $3 comma 500$ college students, $420$ reported that they do not own a laptop. Construct a $95 percent sign$ confidence interval for the proportion of college students who do not own a laptop. Is this proportion significantly different from $25 percent sign$ , which was the value a decade ago?

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문제 5객관식

A survey was conducted among $1500$ city residents to determine if they support a new public park project. Out of the respondents, $1200$ said they support the project, while $300$ said they do not.

a. Construct a $95 percent sign$ confidence interval estimate of the proportion of residents who support the project.

b. Based on your result from part a, can you conclude that the majority of residents support the project?

문제 6객관식

A research group asked $1250$ adults if they support a proposed tax reform, and $58 percent sign$ said yes. If these data are used to construct a confidence interval, which interval is wider? The $95 percent sign$ confidence interval or the $85 percent sign$ confidence interval? Why?

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문제 7객관식

A medication is used to treat type $2$ diabetes. In a clinical study, $4400$ patients were given the medication, and $198$ reported experiencing gastrointestinal discomfort. Construct a $99 percent sign$ confidence interval for the proportion of patients who may experience this side effect.

문제 8객관식

In a poll of $1500$ registered voters, $1035$ said that they planned to vote in the upcoming election. Construct a $95 percent sign$ confidence interval for the proportion of all registered voters who plan to vote. Write a statement that correctly interprets the confidence interval.

문제 9객관식

In a survey of $950$ households, $418$ reported having at least one pet. Construct a $95 percent sign$ confidence interval estimate of the proportion of all households with at least one pet.

It is believed that the true proportion is $0.45$ . Do these results provide strong evidence against that belief?

문제 10객관식

Determine the critical value $z sub alpha over 2$ for an $88 percent sign$ confidence interval.

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문제 11객관식

Determine the critical value $z sub alpha over 2$ for a $92.5 percent sign$ confidence interval.

문제 12객관식

A local radio station conducted an online poll asking listeners whether they believe the city should ban fireworks. Out of $850$ respondents, $765$ said the city should not ban fireworks, while $85$ said it should.

(1) Construct a $95 percent sign$ confidence interval estimate for the proportion of the population that believes the city should not ban fireworks.

(2) Based on your confidence interval, can you conclude that the majority of the population does not support a fireworks ban?

(3) Identify a flaw in this survey and explain what can actually be inferred about the population.

문제 13객관식

In a recent football cup, on‐field decisions were referred to the Video Assistant Referee (VAR) system $150$ times. Of those reviews, $40$ calls were overturned. Construct a $99 percent sign$ confidence interval for the true proportion $p$ of VAR reviews that result in an overturned decision.

문제 14객관식

In a recent tennis tournament, men's singles players used challenges on $120$ line calls made by the chair umpire. Among those challenges, $36$ were found to be successful (the original call was overturned). Construct a $99 percent sign$ confidence interval for the true proportion $p$ of successful challenges by men in singles matches.

문제 15객관식

A new antihistamine, $X$ , is known to cause dry mouth. In clinical trials, $200$ subjects received $X$ , and $50$ reported dry mouth. In a separate placebo group of $60$ subjects, $6$ reported dry mouth. Construct a $95 percent sign$ confidence interval for the true proportion $p$ of placebo‐treated subjects who experience dry mouth.

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문제 16객관식

A parapsychology researcher tested whether participants could 'remote view' the color of a hidden card. On each trial, a participant guessed red or black for a face‐down playing card’s color. In over $250$ independent trials, participants were correct $110$ times. Construct a $99 percent sign$ confidence interval for the true proportion $p$ of correct guesses.

문제 17객관식

A company wants to compare the effectiveness of two training programs. In Program A, $120$ out of $200$ employees passed a certification exam. In Program B, $95$ out of $200$ employees passed. Construct a $95 percent sign$ confidence interval for the difference in population proportions $p sub 1 minus p sub 2$ .

문제 18객관식

A national survey of $650$ public library patrons found that $47.2 percent sign$ reported using the library’s digital resources at least once per week. Among the $650$ patrons surveyed, how many reported weekly use of digital resources?

문제 19객관식

In a recent survey of $250$ software developers, $200$ reported that code reviews are the most important quality‐assurance practice. Construct an $80 percent sign$ confidence interval estimate of the true proportion $p$ of all software developers who believe code reviews are the most important.

문제 20객관식

A study compares the average number of hours students sleep before and after implementing a new bedtime routine. The $95 percent sign$ confidence interval for the mean difference in sleep hours is given as $- 3.2 < μ_{d} < - 0.4$ . Based on this interval, what can you conclude about the claim that the new routine has no effect on sleep duration, that is, $mu sub d equals 0$ ?

문제 21객관식

In a Gallup poll of $450$ employed adults, $82 percent sign$ said they prefer working remotely at least part of the time. Among the $450$ respondents, how many said they prefer working remotely?

문제 22객관식

A factory produces LED light bulbs in batches of $200$ . The number of defective bulbs found in each of $12$ consecutive batches is as follows: $2 comma 3 comma 2 comma 4 comma 5 comma 7 comma 8 comma 10 comma 13 comma 15 comma 18 comma 22$ . Based on this data, should the production process be adjusted?

문제 23객관식

A snack food company inspects the number of stale chips in each of $12$ consecutive batches (each batch contains $300$ bags). The number of stale chips found in each batch is: $1 comma 2 comma 2 comma 3 comma 4 comma 6 comma 7 comma 9 comma 11 comma 13 comma 16 comma 19$ . Should the quality control process be reviewed for potential issues?

문제 24객관식

In a poll of $950$ college students, $55 percent sign$ reported that they prefer online classes to in-person classes. Construct a $95 percent sign$ confidence interval for the proportion of all college students who prefer online classes. Does the interval suggest that more than half of all college students prefer online classes?

문제 25객관식

Given the population $3 comma 8 comma 10 comma$ suppose samples of size $n$ equals $2$ are selected at random with replacement. Let $Y$ be the sample proportion of numbers greater than $5$ in each sample. What is the mean of the sampling distribution of the sample proportion of numbers greater than $5$ ?

문제 26객관식

A nutritionist conducts a study to determine whether a dietary intervention can increase the probability of conceiving a girl. Among $600$ babies born to mothers following the dietary intervention, $510$ were girls. In a separate study, $350$ babies were born to mothers following a different diet aimed at increasing the probability of a boy, with $210$ boys born. Construct the $95 percent sign$ confidence interval estimates of the percentages of girls and boys born for each diet. Compare the results and provide a conclusion.

문제 27객관식

In a study of smoking cessation, $250$ patients were given a nicotine replacement therapy (NRT) treatment. After six months, $18.4 percent sign$ of the patients were confirmed by biochemical tests to have quit smoking, and $35.2 percent sign$ reported quitting. Construct two $95 percent sign$ confidence intervals for the percentage of patients who quit smoking (one based on biochemical confirmation and one based on self-reporting). Compare the results and draw conclusions.

문제 28객관식

A study on corporate leadership compares the heights of CEO candidates and their opponents in $100$ board elections. In the study, it was found that in $60$ of the elections, the CEO candidate was taller than their opponent. The remaining $40$ elections had the opponent taller than the CEO candidate. Construct a $95 percent sign$ confidence interval for the true proportion of CEO candidates who are taller than their opponents. Based on the results, does it appear that greater height is an advantage for CEO candidates? Why or why not?

문제 29객관식

A researcher wants to estimate the percentage of adults who can roll their tongue. The researcher assumes that $35 percent sign$ of adults have this ability (based on prior studies). To estimate the true proportion with a margin of error of $4$ percentage points and a $99 percent sign$ confidence level, what sample size is needed?

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문제 30객관식

A researcher wants to estimate the percentage of adults who can cross their eyes. A previous study shows that $8 percent sign$ of adults have this ability. The researcher wants a $90 percent sign$ confidence level and a margin of error of $3$ percentage points. What sample size is needed to estimate the true proportion of adults who can cross their eyes with the given margin of error?