In a study, researchers wanted to measure the effect of alcohol on the hippocampal region, the portion of the brain responsible for long-term memory storage, in adolescents. The researchers randomly selected 11 adolescents with alcohol use disorders to determine whether the hippocampal volumes in the alcoholic adolescents were less than the normal volume of 9.02 cm. An analysis of the sample data revealed that the hippocampal volume is approximately normal with no outliers and x= 8.04 cm and s =0.7 cm. Conduct the appropriate test at the a = 0,01 level of significance State the null and alternative hypotheses. Ho: (Type integers or decimals. Do not round.) Identify the t-statistic. to = (Round to two decimal places as needed.) Identify the P-value. P-value = (Round to three decimal places as needed.) Make a conclusion regarding the hypothesis. V the null hypothesis. There sufficient evidence to claim that the mean hippocampal volume is

Neurologists have found that the hippocampus, a structure located in the brain, plays an important role in short-term memory. Data was collected on 21 Vietnam veterans with combat related post-traumatic stress disorder. Magnetic resonance imaging was used to measure the volume of the right hippocampus (in cubic millimeters) of each subject, while the verbal memory retention of each subject was measured by the percent retention subscale of the Wechsler Memory Scale. The least squares line relating verbal memory (y) with right hippocampal volume (x) was found to be 4 + 3x. The slope of the regression line can be interpreted in the following way: ŷ = When right hippocampal volume decreases by one cubic millimeter, the verbal memory score increases by 3%. When right hippocampal volume decreases by one cubic millimeter, the verbal memory score increases by 4%. When right hippocampal volume increases by one cubic millime decreases by 3%. the verbal memory score When right hippocampal volume…

The toco toucan, the largest member of the toucan family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, such as being a refined adaptation for feeding. However, the large surface area may also be an important mechanism for radiating heat (and hence cooling the bird) as outdoor temperature increases. Here are data for beak heat loss, as a percent of total body heat loss from all sources, at various temperatures in degrees Celsius. [Note: The numerical values in this problem have been modified for testing purposes.]   Temperature (oC)(oC) 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Percent heat loss from beak 33 32 33 32 39 43 56 48 44 49 44 56 58 60 60 63 The equation of the least-squares regression line for predicting beak heat loss, as a percent of total body heat loss from all sources, from temperature is: (Use decimal notation. Enter the values of the intercept and slope rounded to two…

What is a skewed distribution?

In a study, researchers wanted to measure the effect of alcohol on the hippocampal region, the portion of the brain responsible for long-term memory storage, in adolescents. The researchers randomly selected 13 adolescents with alcohol use disorders to determine whether the hippocampal volumes in the alcoholic adolescents were less than the normal volume of 9.02 cm. An analysis of the sample data revealed that the hippocampal volume is approximately normal with no outliers and x = 8.16 cm3 and s = 0.7 cm3. Conduct the appropriate test at the a = 0.01 level of significance. State the null and alternative hypotheses. Ho: H H1: H (Type integers or decimals. Do not round.)

In order to ensure that there is not a large disparity in the quality of education at various schools in a school district, the school board wants to make sure that the variance of the mean standardized-test scores for all students at each school in the district is less than 2. To test this claim, they looked at the mean student scores for the standardized test from a random sample of 27 schools in the district. The results from the survey found that the overall mean was a score of 209.740 with a standard deviation of 1.210. With α=0.05, perform a hypothesis test to determine if the variance is less than 2. Assume that the district standardized-test scores are normally distributed.   Step 2 of 3: Compute the value of the test statistic. Round your answer to three decimal places.

The toco toucan, the largest member of the toucan family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, such as being a refined adaptation for feeding. However, the large surface area may also be an important mechanism for radiating heat (and hence cooling the bird) as outdoor temperature increases. The table contains data for beak heat loss, as a percentage of total body heat loss from all sources, at various temperatures in degrees Celsius. The data show that beak heat loss is higher at higher temperatures and that the relationship is roughly linear. [Note: The numerical values in this problem have been modified for testing purposes.] Temperature (°C) 15 16 17 18 19 20 21 22 23 24 25 26 27 Percent heat loss from beak 33 33 33 31 37 44 56 52 45 54 46 55 57

In a​ study, researchers wanted to measure the effect of alcohol on the hippocampal​ region, the portion of the brain responsible for​ long-term memory​ storage, in adolescents. The researchers randomly selected 24 adolescents with alcohol use disorders to determine whether the hippocampal volumes in the alcoholic adolescents were less than the normal volume of 9.02 cm3. An analysis of the sample data revealed that the hippocampal volume is approximately normal with no outliers and x=8.04 cm3 and s=0.7 cm3. Conduct the appropriate test at the α=0.01 level of significance.                                                                                                                                                            State the null and alternative hypotheses.…

Snow avalanches can be a real problem for travelers in the western United States and Canada. A very common type of avalanche is called the slab avalanche. These have been studied extensively by David McClung, a professor of civil engineering at the University of British Columbia. Suppose slab avalanches studied in a region of Canada had an average thickness of u = 67 cm. The ski patrol at Vail, Colorado, is studying slab avalanches in its region. A random sample of avalanches in spring gave the following thicknesses (in cm). 59 51 76 38 65 54 49 62 68 55 64 67 63 74 65 79 (i) Use a calculator with sample mean and standard deviation keys to find x and s. (Round your answers to two decimal places.) X= cm S= cm (ii) Assume the slab thickness has an approximately normal distribution. Use a 1% level of significance to test the claim that the mean slab thickness in the Vail region is different from that in the region of Canada. (a) What is the level of significance? State the null and…

In a study, researchers wanted to measure the effect of alcohol on the hippocampal region, the portion of the brain responsible for long-term memory storage, in adolescents. The researchers randomly selected 17 adolescents with alcohol use disorders to determine whether the hippocampal volumes in the alcoholic adolescents were less than the normal of 9.02 cm3. An analysis of the sample data revealed that the hippocampal volume is approximately normal with no outliers and x = 8.17 cm3 and s = 0.7 cm3. Conduct the appropriate test at the a = 0.01 level of significance. to = -5.01 P-value = 0 Make a conclusion regarding the hypothesis.  Reject the null hypothesis. There is sufficient evidence to claim that the mean hippocampal volume is less than _____ cm3.