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I'm having problems with one of the problems on my statistics homework. I don't necessarily need the answer from you, but I really need help understanding what I need to do! Please and thank you :)

Problem: It has been reported that, during the prime mating season, female crickets are more attracted to males that have high chirp rates. Generally, the average cricket chirps at a rate around 60 per second. Use this value as the benchmark test value. Chirp rates are thought to be related to overall condition and the higher the better. Eight mature male crickets were placed on a high protein diet. After eight days several attributes of the calling behaviour of these crickets was assessed. One of the attributes was the chirp rate (chirps/sec). The raw data for this attribute appear below in Table one. Does this data support the investigators’ claim that a high protein diet is associated with higher call rates? Let alpha = 0.025 and assume that the chirp rate data come from a normally distributed population. Table 1: chirp rates (chirps/sec) of 8 mature crickets on a high protein diet: 68 80 60 53 75 72 66 71


  1. The appropriate null/alternative hypothesis pair tested by the study investigators is: a. Ho: μd = 60; Ha: ≠ < 60 b. Ho: μ < 60; Ha: μ ≥ 60 c. Ho: μd ≥ 60; Ha: μ < 60 d. Ho: μ ≥ 60; Ha: μ < 60 e. Ho: μd < 60; Ha: μ ≥ 60 f. Ho: μ = 60; Ha: ≠ < 60, g. Ho: μ ≤ 60; Ha: μ > 60

  2. t-test =

  3. The P-value is between... Low: _ and High: _

  4. The statistical decision is: reject Ho, fail to reject Ho, fail to reject Ha, or reject Ha?

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What have you done until now? –  Raskolnikov Sep 18 '12 at 7:31
What are $\mu$ and $\mu d$? What does "≠ < 60" mean? –  joriki Sep 18 '12 at 8:19
Hello! I've actually managed to do most of the problem now. I got answer g for #1, and t-test=2.69. But calculating p-values has still got me a bit. –  Becky Sep 18 '12 at 19:47
Ignoring comments is one of the most reliable ways of deterring people from spending time on your question. –  joriki Sep 19 '12 at 8:45
I apologize times a ton! I was so very new to this website back when I asked this question and I didn't know how to tell when someone had commented back. Once again, I'm very sorry! –  Becky Mar 4 '13 at 17:20
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