Week 1 Discussion

Week 1 Discussion

Based on the definitions in Section 1.3 and Section 1.4 from the textbook, is a convenience sample obtained by using simple random sampling?  Why or why not? Clearly state your reasoning.

Week 2 Discussion

Is the shape of the distribution shown in the frequency histogram below uniform, bell shaped, skewed right or skewed left?  Clearly indicate your reasoning.

Week 3 Discussion

In Section 3.1 Measures of Central Tendency, there is a discussion of what it means for a statistic to be resistant.  Is the mean resistant? Why or why not?  Is the median resistant? Why or Why not?

Week 4 Discussion

In Section 3.5, The Five-Number Summary is defined.  What is The Five-Number Summary and how is it used to construct a boxplot?

Week 5 Discussion

What is a lurking variable?  When a lurking variable is introduced or included in the analysis, where the association changes (or causes us to rethink the direction of an association) (inverts), or goes away, is an instance of (or situation called) what?

Week 6 Discussion

In the game of Craps, a pair of fair dice are rolled and the number facing upward of each die are added.  These outcomes are displayed in Section 5.1, Figure 3, on page 257 of the textbook.  A field bet is a single roll, where the person wins by rolling a 2, 3, 4, 9, 10, 11 or 12.  The person loses by rolling a 5, 6, 7 or 8.  Using the Complement Rule, defined in Section 5.2, page 271 of the textbook, to compute the probability a person wins a field bet on a single roll.  Write the answer as as a simplified fraction.

Week 7 Discussion

1) Once certain conditions are met, the number of arrangements of r objects from n spacedistinct objects, where repetition is not allowed, can be determined using combinations or permutations.  Which condition needs to be determined before deciding to use combinations or permutations to calculate the number of arrangements of r spaceobjects from n spacedistinct objects, where repetition is not allowed?

2) When using combinations or permutations, is it possible that r greater than n space?  Why or why not?

Week 8 Discussion

Over a period of time it has been observed that a given archer can hit a target on a single trial with a probability equal to 0.8.  Suppose the archer fires four arrows at the target.

Using a TI-84 calculator the following probabilities are calculated.  Interpret what these calculations mean (referencing the above information).

1) binompdf(4,0.8,2) = 0.1536

2) 1-binomcdf(4,0.8,1) = 0.9728

These are functions in the calculator for a binomial distribution.  To locate on a TI-84 calculator, press the 2nd button, then CATALOG (the zero button), then press APPS button and select either binompdf( or binomcdf(.

Week 10 Discussion

In Section 8.1, The Central Limit Theorem is discussed.  What is The Central Limit Theorem?

Week 11 Discussion  – no entry

Week 12 Discussion

In Section 10.2 a P-value is discussed.  Describe what a P-value is and how is it used in Hypothesis Testing.