A meteorologist preparing a talk about global warming compiled a list of weekly low temperatures (in degree s Fahrenheit) he observed at his southern Florida home last year. The coldest temperature for any week was 36°F, but he inadvertently recorded the Celsius value of 2°. Assuming that he correctly listed all the other temperatures, explain how this error will affect these summary statistics: a) measures of center: mean and median. b) measures of spread: range, IQR, and standard deviation.

Question
Binomial probability
asked 2020-11-27
A meteorologist preparing a talk about global warming compiled a list of weekly low temperatures (in degree s Fahrenheit) he observed at his southern Florida home last year. The coldest temperature for any week was 36°F, but he inadvertently recorded the Celsius value of 2°. Assuming that he correctly listed all the other temperatures, explain how this error will affect these summary statistics:
a) measures of center: mean and median. b) measures of spread: range, IQR, and standard deviation.

Answers (1)

2020-11-28
a) The median will remain unchanged, while the mean will decrease. Because the lowest value decreased and the median is not influenced by one outlier while the mean is influenced by it.
b) The range and standard deviation will increase, while the IQR remains unchanged. Because the IQR is unaffected by an outlier, while the range and standard deviation are influenced by it.
Result: a) Median unchanged, mean decreases
b) Range and standard deviation increase, IQR unchanged
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Relevant Questions

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Suspect was Armed:
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White - 1176
Hispanic - 378
Total - 2097
Suspect was unarmed:
Black - 60
White - 67
Hispanic - 38
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This just means that the percentage of times that both things happen equals the individual percentages multiplied together (Only if they are Independent of each other).
Therefore, if a person's race is independent of whether they were killed being unarmed then the percentage of black people that are killed while being unarmed should equal the percentage of blacks times the percentage of Unarmed. Let's check this. Multiply your answer to part a (percentage of blacks) by your answer to part b (percentage of unarmed).
Remember, the previous answer is only correct if the variables are Independent.
d) Now let's get the real percent that are Black and Unarmed by using the table?
If answer c is "significantly different" than answer d, then that means that there could be a different percentage of unarmed people being shot based on race. We will check this out later in the course.
Let's compare the percentage of unarmed shot for each race.
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Think of it this way. If you went to a college that was 90% female and 10% male, then females would most likely have the highest percentage of A grades. They would also most likely have the highest percentage of B, C, D and F grades
The correct way to compare is "conditional probability". Conditional probability is getting the probability of something happening, given we are dealing with just the people in a particular group.
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