or

### Statistics

Continues for 1 more pages »

# Statistics

By | March 2013
Page 1 of 2
(Ch. 1-3)

True/False section.

F1.Any time there is a statistical association between events, we can assume there is causation.

T2.A binary variable is categorical data that can take only two values; for example: college grad = 1, not college grad = 0.

T3.Likert scales measure ordinal data with coding; the more scale points used, the coarser the scale.

T4.Characteristics of a population are called parameters; characteristics of a sample are called statistics.

T5.Of the seven sampling methods, only cluster sampling uses geographical areas as strata.

Problem section. Show all your work and uses only your own words (not words from the textbook)

A. Using the data below, create a scatter plot with EXCEL. Describe the relationship between the two variables (Unit Price and Units Sold) using the Figures on pp. 84-85. Unit Price: 5, 4, 6, 5.5, 6.25, 7

Units sold: 17, 16, 13, 17, 12, 10

• It’s fast and quick
• It costs less because the samples can be used from anywhere that is accessible to the person conducting the research.

• Results are biased since there is a lack of representative people in the study. • Results may not be replicable when repeated

C. What is “skewness”? Will a right-skewed distribution have most of the values clustered on the right? Explain your answer!

In a histogram skewness is characterized by the direction of its longer tail, and if both tails are the same, it is considered symmetric. No, a right-skewed distribution has most of its values clustered on the left, hence why it is positively skewed. As our text book illustrates, right-skewed histograms are used by business data where it is often bounded by zero on the left but unbounded on the right.

D. What is a histogram and how do you decide how many bins...

#### Rate this document

What do you think about the quality of this document?