Question

In: Statistics and Probability

A.) Suppose that we run the exact same experiment 100 times and find a statistically significant...

A.) Suppose that we run the exact same experiment 100 times and find a statistically significant difference 30 times out of 100 using an alpha level of .05. What is the best estimate of our statistical power?

a) a difference between means is very likely to be detected

b) the significance level set by the researcher must be high

c) the probability of type I error is very high

d) Your study will likely be inconclusive

B) A researcher believes that dogs can smell fear, so he conducts an experiment with blindfolded dogs next to a person who is watching either a scary or a funny movie. What is the null hypothesis (Ho)?

a) dogs can smell fear

b) dogs cannot smell fear

c) that the probability value will be below 0.05

d) that there will be a statistically significant result

Solutions

Expert Solution

A.) Suppose that we run the exact same experiment 100 times and find a statistically significant difference 30 times out of 100 using an alpha level of .05. What is the best estimate of our statistical power?

So 30 time out of 100 we find statistically significant difference.

Statistical power, or the power of a hypothesis test is the probability that the test correctly rejects the null hypothesis. i.e the probability of accepting the alternative hypothesis if it is true.

So we have rejected null hypothesis 30 time out of 100 times.

Now Power = P ( Reject H0 | H1 is true )

Since using an alpha level of .05 , runing the same experiment , we find a statistically significant difference 30 times out of 100 ( which implies reject H0 30 times ) whereas it should be 5 times or less out of 100.

Hence correct option is

a) a difference between means is very likely to be detected

B) A researcher believes that dogs can smell fear, so he conducts an experiment with blindfolded dogs next to a person who is watching either a scary or a funny movie. What is the null hypothesis (Ho)?

Here null and alternative hypothesis will be

H0 : dogs can smell fear

H1 : dogs can not smell fear

Hence correct option is

a) dogs can smell fear


Related Solutions

A.) Suppose that we run the exact same experiment 100 times and find a statistically significant...
A.) Suppose that we run the exact same experiment 100 times and find a statistically significant difference 30 times out of 100 using an alpha level of .05. What is the best estimate of our statistical power? a) a difference between means is very likely to be detected b) the significance level set by the researcher must be high c) the probability of type I error is very high d) Your study will likely be inconclusive B) A researcher believes...
1 In a research report from an experiment, the term a statistically significant difference is used...
1 In a research report from an experiment, the term a statistically significant difference is used to indicate ____________ . A. that the there is a very low probability (i.e., 5% or less) the difference obtained in the study could happen by chance B. that the there is a high probability (i.e., 95% or more) the difference obtained in the study could happen by chance C. that the difference is large D. b & c 2 determining a person’s height...
Looking to find what area needs to be focused on that is statistically significant Dine In...
Looking to find what area needs to be focused on that is statistically significant Dine In (1)/Take Out (2) Satisfaction with Service Satisfaction with Food Driving Distance to Restaurant Total Bill Overall Satisfaction 1 4 4 5 10 4 1 2 3 5 15 3 1 3 3 10 10 3 1 5 5 12 15 5 2 3 4 10 25 3 2 2 4 15 25 3 2 3 4 10 26 3 1 4 3 16 27...
How do we check if the independent variables are statistically significant and contribute to the multiple...
How do we check if the independent variables are statistically significant and contribute to the multiple regression models?
2. A researcher posted that based on a random sample they did not find statistically significant...
2. A researcher posted that based on a random sample they did not find statistically significant evidence that the proportion of people following appropriate distancing and mask guidelines was different than 0.50. a. State the null and alternative hypotheses. b. How many sides does this test have? c. Briefly explain what the researcher meant by “they did not find statistically significant evidence”. 3. To test the claim that the percentage of voters that voted in the last presidential election is...
We claim that the body mass index (BMI) for men is statistically the same as the...
We claim that the body mass index (BMI) for men is statistically the same as the BMI for women. Data from a random sample of 40 men and 40 women is presented below: BMI-M BMI-F Mean 25.9975 Mean 25.74 Standard Error 0.542448 Standard Error 0.974862 Median 26.2 Median 23.9 Mode 23.8 Mode 19.6 Standard Deviation 3.430742 Standard Deviation 6.16557 Sample Variance 11.76999 Sample Variance 38.01426 Kurtosis -0.13645 Kurtosis 1.517743 Skewness 0.356785 Skewness 1.189501 Range 13.6 Range 27.2 Minimum 19.6 Minimum...
Suppose a coin is tossed 100 times and the number of heads are recorded. We want...
Suppose a coin is tossed 100 times and the number of heads are recorded. We want to test whether the coin is fair. Again, a coin is called fair if there is a fifty-fifty chance that the outcome is a head or a tail. We reject the null hypothesis if the number of heads is larger than 55 or smaller than 45. Write your H_0 and H_A in terms of the probability of heads, say p. Find the Type I...
We want to assess whether there is a statistically significant association between two variables. Below are...
We want to assess whether there is a statistically significant association between two variables. Below are pairs of variables, along with their method of measurement. Indicate, justifying it in two lines, for each pair, which statistical test you would use. a) Total Cholesterol (mmol/l) and Sex (Male/Female). b) Red blood cells (millions/microlitre of blood) and Body Mass Index (kg/m2). c) Foot Pain (Severe/Levere) and Obesity (Yes/No). d) Marital status (Single/Married/Divorced) and Educational level (Primary/Secondary/University studies). e) Type 2 diabetes (Yes/No)...
Suppose we perform a binomial experiment 50 times where the probability of success on any given...
Suppose we perform a binomial experiment 50 times where the probability of success on any given trial is 0.20. Which of the following is correct? μ = 10 and σ = 3.16 μ = 8 and σ = 3.16 μ = 10 and σ = 2.83 μ = 8 and σ = 2.83 Suppose the average number of Funko Pops owned by a Statistics instructor is 7 with a standard deviation of 2.3 Pops. What would be the z-score of...
If we could draw many random samples from the same population, and each time we ran the exact same regression
  If we could draw many random samples from the same population, and each time we ran the exact same regression, then we would get the same regression coefficients but different standard errors.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT