数据分析习题1(1)

Your Answer Score

Incorrect 0.00

Total 0.00 / 1.00

Question ExplanationThis question refers to the following learning objective(s):

Question confounding variables and sources of bias in a given study.

Question 5

As part of a statistics project, Andrea would like to collect data on household size in her city. To do so, she asks each person in her statistics class for the size of their household, and reports that her sample is a simple random sample. However, this is not a simple random sample. Which of the following is the best reasoning for why this is not a random sample that is appropriate for this research question?

Your Answer

Andrea did not use any randomization; she took a convenience sample.

Andrea did not use a stratified sample.

Andrea did not use a random number table to randomize the order in which she collected thstudents’ responses, so the sample cannot be random.

Andrea asked everybody in her class instead of asking her classmates to volunteer.

Total

Question ExplanationThis question refers to the following learning objective(s):

Distinguish between simple random, stratified, and cluster sampling, and recognize the benefits and drawbacks of choosing one sampling scheme over another.

Question 6

Which of the following is one of the four principles of experimental design?

Your Answer Score Explanation

stratify

cluster

block Correct 1.00 The four principles of experimental design are contro

non-response

Total 1.00 / 1.00

Question ExplanationThis question refers to the following learning objective(s):

Identify the four principles of experimental design and recognize their purposes:

? control any possible confounders,

? randomize into treatment and control groups,

? replicate by using a sufficiently large sample or repeating the experiment, ? block any variables that might influence the response.

Question 7

Which of the below data sets has the highest standard deviation? You do not need to calculate the exact standard deviations to answer this question.

Your Answer Score Explanation

0, 25, 25, 25, 25, 25, 25

0,1,2,3,4,5,6

0, 100, 200, 300, 400, Correct 1.00 500, 600

The dataset with the least repeated observations tha

most variability, hence the highest standard deviation

0,1,1,1,1,1,2

Total 1.00 / 1.00

Question ExplanationThis question refers to the following learning objective(s):

Note that there are three commonly used measures of center and spread:

? center: mean (the arithmetic average), median (the midpoint), mode (the most frequent observation)

? spread: standard deviation (variability around the mean), range (max-min), interquartile range (middle 50% of the distribution)

Question 8

The distribution of housing prices in a country where 25% of the houses cost below $350,000, 50% of the houses cost below $450,000, 75% of the houses cost below $1,000,000 and there are a meaningful number of houses that cost more than $6,000,000 is most likely

Your Answer Score Explanation

left skewed

right skewed Correct 1.00 There is a long tail on the right side of the di

uniform

symmetric

Total 1.00 / 1.00

Question ExplanationThis question refers to the following learning objective(s):