(1.2)
School letter grades like A, B, C, D are what type of data?
Ordinal
To select a sample of 100 employees of Company X, You assign a number to every employee in the company database from 1 to 1000, and use a random number generator to select 100 numbers. This is what type of sample?
Simple Random Sample
Calculate the IQR from the following list of values:
10, 25, 30, 8, 27, 17, 25
IQR = 17
The mean height of a woman is 65 inches and standard deviation is 3.5inches. Ms. Salinas has a height of 70 inches. What is her z-score?
Z=1.42
The mean of sampling distribution is 13.2. What is the mean of the population?
13.2
True or false: We can represent categorical data using a histogram.
False, we can only represent quantitative data in a histogram.
All employees of the company are listed in alphabetical order. From the first 10 numbers, you randomly select a starting point: number 6. From number 6 onwards, every 10th person on the list is selected (6, 16, 26, 36, and so on), and you end up with a sample of 100 people. What type of sample is this?
Systematic Sample
Calculate the standard deviation for the following data: 2, 3, 4
1
The mean score on the Chapter 3 quiz was a 37.29 with a standard deviation of 12.07. What is the probability of getting at least a 50 on the quiz?
Z=1.05
probability: 0.1469
If you want to reduce the spread of your sampling distribution, what should you do?
Increase the sample size
The number of decayed teeth a dentist finds in your mouth is what type of variable?
Discrete
A scientist found that more that ice cream is eaten, the more people drown. At the beach, he slaps the ice cream out of his best friends hand and yells, "don't eat that or you will drown in the water!!!!!!" What type of variable would he be failing to account for?
Confounding variable (summer months)
When comparing Graph A to Graph C, which measures of center and Spread would you use?
Median and IQR
The empirical rule says that roughly 95% of the data should be how close to the mean?
Within two standard deviations (higher and lower).
A sample of 25 has a distribution that is skewed right with a mean of 11 and standard deviation of of 5. What is the mean and standard error of the sampling distribution?
mean = 11
standard error = 1
How many nominal variables are in the data below?
1
The company has 800 female employees and 200 male employees. You sort the population into two groups based on gender. Then you use random sampling on each group, selecting 80 women and 20 men, which gives you a representative sample of 100 people. What type of Sampling is this?
Stratified Random Sample
In Which graph is this definitely true: mean > median
Graph II
10 and 14
A sampling distribution of size 100 has a standard error of 2. What was the standard deviation of the sample?
standard deviation = 20
Which of the following are continuous variables?
a.) Amount of fat in sausage
b.) Weight of a 17 yr old student
c.) Number of Trout in a Lake
d.) Volume of water in a cup of tea
a, b, and c
Researchers want to learn about alcohol consumption rates at a certain college. They decide to set up a booth on campus where students can stop and take a questionnaire that is not anonymous in regards to how much and how often they consume alcohol. What type of bias does this have?
Non Response Bias
Order the Standard Deviation for smallest to largest
Brand A, Brand C, Brand B
A set of data has a mean of 5 and standard deviation of 1. What is the value of the 80th percentile in terms of the data?
5.84
A sampling distribution has a standard error of 4. The sample had a standard deviation of 20. What was the sample size?
Sample size = 25