1). The following table displays the weights for computing the principal components and the data for two Observations. The mean and standard deviation for x₁ are 4.2 and 1.4, respectively. The mean and standard deviation for x₂ are 6.8 and 4.8, respectively. Compute the first principal component score for Observation

Weights	PC1
x1	−0.72
x2	−0.85
	x1	x2
Observation 1	4.45	12.08
Observation 2	4.56	8.62
Variance	3.36
Variance Percentage	78.323221

a). −0.293

• b). −0.742

• c). 0.949

• d). 0.612

  2). When a predictive model is made overly complex to fit in the quirks of given sample data, it is called ______.

• a). oversampling

• b). over fitting

• c).partitioning

• d). distribution

  3). The process of dividing a data set into a training, a validation, and an optimal test data set is called ________.

  a). overfitting

• b). oversampling

• c). optional testing

• d). data partitioning

  4). Consider the partial data set in the table represents online hours spent shopping by age and income. Using the min-max transformation to normalize Income, what is the average standard deviation of Income for the chart provided? Use the min-max transformation to normalize the observations for Income spent online.

• ID	Income	Age	Online Hours
  2201	62,000	48	2
  2202	58,000	52	4
  2203	53,000	44	5
  2204	22,000	28	7
  2205	43,000	33	4
  2206	48,000	35	3

•  
a). 1

b). 6417

c). 0

d). 0.6997