Straighterline Introduction to Statistics exam questions and answers
22 views 1 purchase
Course
StraighterLine
Institution
StraighterLine
Straighterline Introduction to Statistics exam questions and answers
used to find events of the type events of the type "A or B"
General Multiplication Rule - Answer-P(A and B) = P(A) * P(B | A)
Used for events of the type "A and B"
or when A and B are independent:
P(A and B) = P(A) * P...
straighterline introduction to statistics exam que
finding an outlier using iqr answer an observati
simpsons paradox answer when a lurking variable
Written for
StraighterLine
StraighterLine
All documents for this subject (481)
Seller
Follow
Rusenna
Reviews received
Content preview
Straighterline Introduction to Statistics exam questions and answers
Four steps in the process of statistics - Answer-1. Producing Data
2. Exploratory Data Analysis
3. Probability
4. Inference
Categorical variable - Answer-places individuals into one of several groups
Two types: nominal and ordinal
Quantitative Variable - Answer-represents a measurement or a count
Two types: Interval and ratio
Nominal Variable - Answer-categorical variables where there is no natural order among the categories
Ordinal variable - Answer-categorical variables where there is natural order among the categories
Interval Variable - Answer-a measurement or count for which it makes sense to talk about the difference between values, but it does not make sense to talk about the ratio between values; 0 does not represent the absence of quanitity
Ratio Variable - Answer-quantitative variables for which it makes sense to talk about the
difference between values AND the ratio between values; 0 represents the absence of quantity
What type of variable?:
eye color - Answer-nominal
What type of variable?:
socioeconomic status with categories low, med, high - Answer-Ordinal
What type of variable?:
Temperature - Answer-Interval
What type of variable?:
Income - Answer-Ratio
Visual display and numerical summary for a single categorical variable - Answer-pie chart or bar chart
and category percentages Visual display and numerical summary for a single quantitative variable - Answer-
histogram or stemplot and descriptive statistics
Visual display and numerical summary for C->C - Answer-Two way table and conditional percentages
Visual display and numerical summary for C->Q - Answer-Side by side box plots and descriptive statistics
Visual display and numerical summary for Q->Q - Answer-Scatterplot and correlation coefficient (r)
Standard Deviation Rule - Answer-Approximately 68% of observations fall within 1 sd of the mean, 95% within 2 sd, 99.7% (or virtually all) within 3 sds
Interquartile Range (IQR) - Answer-Middle 50% of the data
IQR= Q3-Q1
Finding an outlier using IQR - Answer-An observation is considered a suspected outlier if it is:
less than Q1 - 1.5(IQR), or
more than Q3 + 1.5(IQR).
Interpreting scatterplots:
1. positive relationship displays as
2. negative relationship displays as - Answer-1. upward slope
2. downward slope
Interpreting Scatterplots:
How to tell if a linear relationship is strong or weak - Answer-closer to -1 is a strong negative linear relationship
closer to +1 is a strong positive linear relationship
close to 0 is a weak linear relationship
Interpreting Scatterplots:
Linear regression - Answer-Finding the line that best fits the pattern of the linear relationship (the line that describes how the response variable linearly depends on the explanatory variable
Interpreting Scatterplots:
Least Squares Regression Line - Answer-Has the smallest sum of squared vertical deviations of the data points from the line.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Rusenna. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R190,70. You're not tied to anything after your purchase.
