Homework day 1 pg 568-70 9.1 9.2 9.4(for turn-in day

Info iconThis preview shows pages 3–6. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Homework: Day 1: pg 568-70: 9.1, 9.2, 9.4 (for turn-in) Day 2: pg 578-80: 9.9-13, 9-16 (16d for turn-in) Chapter 9: Sampling Distributions Section 9.2: Sample Proportions Knowledge Objectives: Students will: Identify the “rule of thumb” that justifies the use of the recipe for the standard deviation of . Identify the conditions necessary to use a Normal approximation to the sampling distribution of . Construction Objectives: Students will be able to: Describe the sampling distribution of a sample proportion . (Remember: “describe” means tell about shape, center, and spread.) Compute the mean and standard deviation for the sampling distribution of . Use a Normal approximation to the sampling distribution of to solve probability problems involving . Vocabulary: Sample proportion – p-hat is x / n ; where x is the number of individuals in the sample with the specified characteristic (x can be thought of as the number of successes in n trials of a binomial experiment). The sample proportion is a statistic that estimates the population portion, p. Key Concepts: Conclusions regarding the distribution of the sample proportion: Shape: as the size of the sample, n, increases, the shape of the distribution of the sample proportion becomes approximately normal Center: the mean of the distribution of the sample proportion equals the population proportion, p. Spread: standard deviation of the distribution of the sample proportion decreases as the sample size, n, increases Sampling Distribution of p-hat For a simple random sample of size n such that n ≤ 0.10N (sample size is ≤ 10% of the population size) The shape of the sampling distribution of p-hat is approximately normal provided np ≥ 10 and n(1 – p) ≥ 10 The mean of the sampling distribution of p-hat is μ p-hat = p The standard deviation of the sampling distribution of p-hat is σ = √(p(1 – p)/n) Sample Proportions, p ̂ • Remember to draw our normal curve and place the mean, p- hat and make note of the standard deviation • Use normal cdf for less than values • Use complement rule [1 – P(x<)] for greater than values Chapter 9: Sampling Distributions Example 1: Assume that 80% of the people taking aerobics classes are female and a simple random sample of n = 100 students is taken. What is the probability that at most 75% of the sample students are female? Example 2: Assume that 80% of the people taking aerobics classes are female and a simple random sample of n = 100 students is taken. If the sample had exactly 90 female students, would that be unusual? Example 3: According to the National Center for Health Statistics, 15% of all Americans have hearing trouble. In a random sample of 120 Americans, what is the probability at least 18% have hearing trouble? Example 4: According to the National Center for Health Statistics, 15% of all Americans have hearing trouble. Would it be unusual if the sample above had exactly 10 having hearing trouble?...
View Full Document

{[ snackBarMessage ]}

Page3 / 11

Homework Day 1 pg 568-70 9.1 9.2 9.4(for turn-in Day 2 pg...

This preview shows document pages 3 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online