Statistics Flashcards
What are statistical measures?
Measure of frequency - Histogram and Frequency Distribution
Measure of central tendency - Mean, Median and Mode
Measure of spread - Standard deviation, Variance and Range
Mean formula
μ = ∑N / Nsum
Median formula
μ = N / Nsum or μ = N+1 / Nsum
Mode formula
Max count of data point
Standard deviation formula
√ ∑(μ -xi)2 / N
Normal distrbution curve what is the % of values distributed?
68.2% = -1sd to +1sd
13.6% = -1sd to -2sd and +1sd to 2sd
1.7% = -2sd to -3sd and +2sd to 3 sd
Formula for Linear Regression
y=b0(intercept) + b1x1(coefficientvariable) + E(error)
Output of logistic regression is binary, true or false?
True
What is log transformation?
Process of transforming a Non linear curve to a linear curve
Sigmoid Curve
Its a non linear curve that is part of Logistic regression
Which Python lib is used for data wrangling?
Pandas
Which Python lib is used for machine learning?
Ski-kit learn
Which Python lib is used for statistical functions?
NumPy
What is the difference between List and Tuple?
List is defined by [] and Tuple by (). List can be modified and Tuple cannot
What is array in Python?
Its a list which is understable by NumPy lib
arr[1:2]. What index value is inclusive and what is not?
1 is inclusive and 2 is noy
How to create arithmatic progression in NumPy array?
Using arrange function
How to convert a 1dim array to 2 dim array in NumPy?
Using reShape
