# Population Standard Deviation Essay

823 Words Aug 30th, 2011 4 Pages
REVIEW EXERCISES
CHAPTER 8 AND 9
PROFESSOR JONAS
WIU-RES
BY DEBRA JAMES

CHAPTER 8 1. High temperature in the United States a meteorologist claims that the average of the highest temperatures in the united states in 98. A random sample of 50 cities is selected, and the highest temperatures are recorded. The data are shown. At a=0.05 can the claim be rejected? a=7.7
97, 101, 99, 99, 100, 94, 87, 99, 108, 93, 96, 88, 98, 97,88, 105, 97, 96, 98, 102, 99, 94, 96, 114, 99, 96, 98, 97, 91, 98, 80, 95, 98, 96, 80, 95, 88, 99, 102, 95, 101, 94, 92, 99, 101, 97, 94, 97, 102, 61.
The claim can be rejected; correct answer may be either above 98 or below it.

2. Salaries for Actuaries nationwide graduates entering the actuarial
There is not sufficient evidence to conclude.

2. Communication times - according to the bureau of labor statistics American time use survey married persons spend an average of 8 minutes per day on phones calls, mail and email, while single persons spend an average of 14 minutes per day on these same tasks. Based on the following information is there sufficient evidence to conclude that single persons spend, on average a greater time each day communicating? Use the 0.05 level of significance.

There is not enough information to ... actual average salary. In each of the following ... At the 0.05 level, does this show sufficient evidence to conclude

3. Teachers’ Salaries - a sample of 15 teachers from Rhode Island has an average salary of \$35,270, with a standard deviation of \$3256. A sample of 30 teachers from New York has an average salary of \$29,512, with a standard deviation of \$ 1431. Is there a significant difference in teachers’ salaries between the two states? Use a = 0.02. Find the 98% confidence interval for the difference of the two means. H0: μ1 - μ2 = 3000 H1: μ1 - μ2 ≠ 3000 where, H0 is the null hypothesis, d = 3000
For hypothesis testing on two means with known variances:
Δ = [(X1 - X2) - d] / {√[ (σ1² / n1) + (σ2² / n2) ] } where, X1 and X2 are the two sample means σ1 and σ2 are the two sample standard deviations n1 and n2 are the two sample sizes
In this case,
X1 = 35,270

## Related Documents

• ###### Gdp and Living Standard Essay

Relationship of GNP and Living Standard Phuong Le SUNY Morrisville State College Project 2- Part 2 Part I: Description of the data set: I collected data from Journal of Statistics Education (JSE). Its original data set which is named “The Statistics of Poverty and Inequality” includes birth rates, death rates, infant death rates, life expectancies for males and females, and Gross National Product for 97 countries in the world divided into 6 groups (97 observations, 8 variables total…

Words: 1791 - Pages: 8
• ###### Essay Sample Standard Deviation Of The Sample Wins

1. Find the mean and standard deviation of the sample WINS: [4 POINTS] Sample Mean: 80.05 Sample Standard deviation: 11.9405 2. Assume that the population is normally distributed, but the population standard deviation is not known. [8 POINTS] (a) Use your sample data to find a 95% confidence interval for the true mean number of wins for all Major League teams: -Next Page (b) State the margin of error of the confidence interval: 5.5883 (c) How can you increase the precision…

Words: 1604 - Pages: 7
• ###### Essay The Standard Deviation Of 16.4

standard deviation of 16.4. This latter, the standard deviation is an indication of the dispersion, or how widely the reported scores spread out around the mean value of 85.1. Here, although the mean and the median are almost identical, the former is preferable because it provides a better representation across the spectrum of data, and therefore a better measure of central tendency (Thorndike & Thorndike-Christ, 2009). But with a mode of 66.0, it shows that some data are far off the mean, however…

Words: 1208 - Pages: 5
• ###### Essay Standard Deviation Of The Second Water

water had 42 ppm of CaCO3 present in all three trials conducted. The standard deviation from these tests was 0. Kroger water had a 46.2 ppm of CaCO3 in the first trial, 50 ppm in the second trial, and 43.2 ppm in the third trial. The standard deviation of the second water sample was 3.41. Crystal Geyser water had a 16.42 ppm of CaCO3 in the first trial, 21 ppm in the second trial, and 22 ppm in the third trial. The standard deviation of the third sample was 2.97. According to the table provided…

Words: 1230 - Pages: 5
• ###### Essay The Units Of Population Of A County Is Measured

and objects are not only named but compared. The following are the types of units of analysis and interpretation a) Rate : For example death rate per thousand are used for analysis of population. b) Ratio : The relative values of two homogeneous facts are represented in ratio, for example men women ratio of population of a county is measured as 9:10. c) Coefficient : When the rate is expressed as per unit instead of per thousand or per hundred then it is called coefficient. Coefficient is computed…

Words: 1544 - Pages:
• ###### Analyzing The Limited Data Of The Standard Deviation Of Demand

to us. More specifically, we looked at the mean and standard deviation of demand for the first 50 days of the simulation. We did this by exporting the data from Littlefield into an Excel document and utilizing the AVG and STDEV functions within it. These functions gave us an average demand of 14.52 jobs per day, and a standard deviation of 4.17 jobs per day for the first 50 days. By comparing these numbers we realized that the standard deviation was nearly 30% of the average daily demand. This told…

Words: 1064 - Pages:
• ###### Essay A Brief Note On The Population Of Town

3500 per year. Result Town A Analysis data in town A shows that the average age of respondent in town A is 41- 50 years and a standard deviation of age is 21 years old. The values within one standard deviation mean that 68% of people in town A between 20-29 and 62-71 age of years. Therefore, based on the mean of age, it can be assumed an older population in town A. Meanwhile, the average of the productive land and production in town A is not significantly different, productive land is 9…

Words: 1052 - Pages:
• ###### Essay Mechanical Deviation Of The Overall Measured Data

The preeminent design of the paper helicopter experiment would comprise of the best mean and standard deviation of the overall measured data. An in depth comparison of the mean value and the standard deviation of each variable will be discussed in relation to a measure suitable for a longer flight time and a more accurate landing. These variables will be discussed relevant to the data and information gathered from our experiment during testing. The ratio of each helicopter will be discussed in order…

Words: 1045 - Pages: 5
• ###### Essay Standard Deviation and Percentage

Steakhouse. The average Remington’s patron statistics are listed in Table 1. Table 1: Demographic Description of the Average Remington’s Patrons ------------------------------------------------- Variable Mean Central Tendency Variance Standard Deviation Age 42 2.09 1.45 Gender Male 0.24 0.49 ------------------------------------------------- Number of Children 1 – 2 0.76 0.87 Income \$50,001 - \$75,000 2.09 1.45 The average Remington’s patron is…

Words: 6617 - Pages: 27
• ###### Standard deviation abstract Essays

Standard Deviation Abstract QRB/501 Standard Deviation Abstract Standard Deviations Are Not Perverse Purpose: The purpose of this article is to illustrate how using statistical data, such as standard deviation, can help a cattleman choose the best lot of calf’s at auction. The statistical data used in these decision making processes can also help the cattleman with future analysis of the lots purchased and existing stock. Research Question: How can understanding the standard deviation…

Words: 1478 - Pages: 6