Characteristics of Data
______________ data is non-numeric in its original state, while ___________ data is numeric.
Qualitative, Quantitative
This measure is sensitive to outliers - and this measure is a remedy for that
Mean, Median
Another term for scaling down raw data to a universal scale of numbers
We can say the sampling distribution of sample means is normal if what is normal?
The population distribution that the samples come from
On May 15th 2001, the wife of Lou Pai filed for divorce after finding out her husband was having an extra-marital affair.
An executive, Lou Pai was forced by a Houston court to liquidate all his assets. He liquated $270M of his stock holdings in this company.
4 months later after liquidating his assets, this company filed for bankruptcy after collapsing under the largest corporate fraud in U.S. history.
Enron
False. Discrete is countable. Continuous has an infinite number of possible data points in an interval.
This is the 50th percentile
Median
The denominator (n-1) in the calculation of sample variance is called what?
degrees of freedom
This would be considered an example of the underestimation or overestimation of mu, a parameter.
Bias
Teaming up with The Weekend and Travis Scott, this artist has the #54 and #66 ranked songs on the Billboard 100 this week.
He is also performing in Phoenix this weekend
Playboi Carti
Date of Birth.
N, O, I, R?
Interval. "Zero" has meaning as somebody could have been born in Year "0".
In finding the value for a respective percentile, this is the 1st step to perform.
Order the values - ascending
Why are the error terms squared before summing them vs. after?
If you summed the error terms before summing them they would approximate zero. Zero would mean no dispersion.
This is a measurement taken on sample
Statistic (examples: x-bar, s, p-bar, median)
A man dies of old age on his 25 birthday. How is this possible?
His birthday was on February 29th.
Amount of data left on your monthly plan if you don't have an unlimited data package.
Discrete or Continuous?
Continuous.
Even though it may say you have 0.75 GB of data remaining, you really have an amount between 0.74 and 0.76. True amount of data left could be an infinite amount of possibilities between 0.74 and 0.76. Which makes it continuous.
This is another term for the 75th percentile
Q3
What is the z-score of a data point with a value of 3, given the below?
x-bar = 6
s^2 = 9
z = -1
z =
(3 - 6) / 9^.5
The sampling distribution of sample means that is selected from a skewed distribution can only be assumed normal if, at least, this number of samples are taken
30
The U.S. military rented out their F-18 at this approximate cost each - for last summer's blockbuster movie.
Name the cost and movie.
$11,000/hr.
Top Gun: Maverick
This type of visualization comes about by filling bins/buckets with observations/data
Histogram
Q1: 12
Q2: 18
Q3: 22
IQR: ?
10
IQR = Q3 - Q1 = 22 - 12
= 10
Using the empirical rule, what is the probability between z-scores of -2 and 0?
47.5% from 34 + 16 - 2.5
between -1 and 0 is 34%
less than -1 is 16%
less than -2 is 2.5%
Is the roll of a dice an example of a continuous or discrete uniform distribution?
Discrete. Cannot have an infinite number of values rolled between then interval 1 and 2, 2 and 3, 3 and 4, etc.
This company lost over $250B of its value on February 2, 2022. It was the single largest one-day loss for a company in U.S. history.
What company was this?
More importantly, what caused such a destruction in value?
Facebook.
Apple's Privacy Notice (ATT) in summer 2022 meant that Facebook and other social media companies (SNAP, etc) could no longer track the cookies (digital drooling) of iPhone users. As a result Facebook revenues fell almost $10B dollars from the previous year.