# Statistics

### QNT 275 Final Exam Section 2 – Item Most Influenced by Outliers

Which of the following is most influenced by outliers?  Mean Explanation: The mean will be the most affected from a single ore small number of outliers. For this reason, the mean is usually not the best measure of central tendency when the distribution is skewed or not [...]Read more

### QNT 275 Final Exam Section 3 – Continuous Random Variable

Which of the following can be represented by a continuous random variable? The average temperature in Tampa, Florida, during the month of July Explanation: A continuous random variable can take an infinitely large range of values. The average temperature can accept any value [...]Read more

### QNT 275 Final Exam Section 4 – Stratified Random Sample

Which of the following meets the requirements of a stratified random sample? A population contains 10 members under the age of 25 and 20 members over the age of 25. The sample will include two people chosen at random under the age of 25 and four people chosen at random over 25. [...]Read more

### QNT 275 Final Exam Section 5 – Regression Analysis

Which of the following violates the assumptions of regression analysis? The error term does not have the normal distribution. Explanation: There are a number of assumptions that must be made in a regression analysis. One of the keys is that the error term has a normal [...]Read more

### QNT 275 Final Exam Section 6 – Frequency Distributions

Frequency distributions may be used to describe which of the following types of data?  Nominal, ordinal, interval, and ratio data Explanation: Frequency distributions simply collect the number of times a value appears in a set. This is used commonly with qualitative data, but [...]Read more

### Cold and Flu Study Statistical Analysis

Which is the Better Medication for both a Sore Throat and a Fever? Medication Study Details Sore throat – Medication A:  Success rate – 90%101 out of 112 trials were successful) Sore throat – Medication B:  Success rate – 83%(252 out of 305 trials were [...]Read more

### Why a Statistician Wanted to Reinforce Airplane Engines during WWII

Abraham Wald, Airplane Engines, and Statistics The statistician who worked with the U.S. Military in this scenario is Abraham Wald. He is well-known for making the correlation between bullet hole location the unexpected results that they produce for aircraft reinforcement. Wald [...]Read more

### Random Sample Confidence Interval – QNT/561 Week 2 Lab

QNT/561 Week 2 Lab – Random Sample A random sample of 90 observations produced a mean x = 25.7 and a standard deviation s = 2.6. a . Find a 95% confidence interval for μ b. Find a 90% confidence inteml for μ c. Find a 99% confidence interval for μ Solution Use the [...]Read more

### Newspaper Reported that Coffee Shops are Overpriced – QNT/561 Week 2 Lab

QNT/561 Week 2 Lab – Coffee Shops are Overpriced A newspaper reported that 50% of people say that some coffee shops are overpriced. The source of this information was a telephone survey of 40 adults . a. Identify the population of interest in this study b. Identify the [...]Read more

### Reading program to improve students’ Japanese reading comprehension – QNT/561 Week 2 Lab

QNT/561 Week 2 Lab – Japanese Language Program In one university, language professors incorporated a 10-week extensive reading program to improve students’ Japanese reading comprehension. The professors collected 277 books originally written for Japanese children and [...]Read more