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Before deciding whether or not to approve a merger among rivals in an industry, the Federal Trade Commission calculates a measure of industry concentration using the market shares of all competitors.  It is called the

You digress from your career in medicine and become interested in venomous snakes. You want to determine if the LD50 for the Black Mamba, Dendroaspis polylepis, (a very dangerous venomous snake from Africa) is different depending on which fang (right or left) delivers the venom. You carefully(!) take 8 snakes and measure the LD50 from the right and left fangs. You get the following results (in mg/kg):   (Biology comment (not useful for answering the question!): LD50 is the dosage at which the venom kills 50% of the mice it’s tested on (a bit gross, I admit))   Snake # 1 2 3 4 5 6 7 8 s right fang 0.973 1.070 0.719 1.289 0.642 0.889 1.039 0.944 0.946 0.203 left fang 0.235 1.286 1.714 0.054 1.299 0.478 0.920 0.157 0.768 0.623 difference 0.738 -0.216 -0.995 1.235 -0.657 0.411 0.119 0.787 0.178 0.764   You may assume that everything is normally distributed.   What test do you decide to use?    

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Here are some data for blood sugar levels in 12 people before and after fasting.  You want to know if there is a difference in blood sugar levels before and after fasting.  Calculate the correct test statistic to use with these data:     Volunteer 1 2 3 4 5 6 7 8 9 10 11 12 Before 109.2 153.9 193.7 140.6 133.3 146.1 156.4 109.8 170.5 162.1 197.8 114.2 After 75.5 125.0 162.3 105.8 105.7 117.8 126.3 77.4 140.9 129.9 171.9 88.2 Difference 33.7 28.9 31.4 34.8 27.6 28.3 30.1 32.4 29.6 32.2 25.9 26.0   All the data are normally distributed.   And some summary statistics you might find helpful:   s Before 148.97 29.77 After 118.89 30.58 Difference 30.075 2.893    

Imagine a market in which firms are identical in size, produce the same products, and earn no economic profits.  This is called

You conduct a classic (= equal variance) t-test and find df = 29, and n1 = 13.  What is n2?  

A competitive environment where there is weak to moderate rivalry among sellers, high entry barriers, weak competition from substitute products, and little bargaining leverage on the part of both suppliers and customers

The advantage of common-sized financial statements is that they

The challenge in defining an industry is that

A strategy map can help identify industry opportunities because it