Data-Based and Statistical Reasoning

Question 1

a symmetrical distribution in which the mean, median, and mode are all the same; 68% of data points occur within one standard deviation of the mean, 95% within two, and 99% within three

Answer 1

normal distribution

Question 2

a normal distribution with a mean of 0 and a standard deviation of 1

Answer 2

standard distribution

Question 3

distributions with differences between their mean, median, and mode; the ____ direction is the direction of the tail of the distribution

Answer 3

skewed distributions (skew)

Question 4

distributions with multiple peaks (but not always multiple modes); data analysis may be performed on the two groups separately

Answer 4

bimodal distributions

Question 5

the difference between the value of the third quartile and first quartile; can be used to determine outliers

Answer 5

interquartile range

Question 6

measurement of variability about the mean; can also be used to determine outliers

Answer 6

standard deviation

Question 7

data that may be a result of true population variability, measurement error, or a non normal distribution

Answer 7

outliers

Question 8

outcomes that cannot occur simultaneously

Answer 8

mutually exclusive outcomes

Question 9

set of outcomes that leaves out no other possible outcomes

Answer 9

exhaustive

Question 10

use a known distribution to determine whether a hypotheses of no difference (the null hypothesis) can be rejected

Answer 10

hypothesis tests

Question 11

is used to determine whether a finding is statistically significant; a ____ of 0.05 is commonly used

Answer 11

comparison of p-value and a selected significance level (α)

Question 12

are a range of values about a sample mean that are used to estimate the population mean; a wider interval is associated with a higher ____ (95% is common)

Answer 12

confidence interval

Question 13

refers to a connection between data (direct, inverse, or otherwise)

Answer 13

correlation

Question 14

refers to one thing causing another thing to happen, cause and effect

Answer 14

causation

Question 15

links the separate concepts of correlation and causation

Answer 15

Hill’s criteria