To evaluate the effect of a treatment, a sample is obtained from a population with a...

To evaluate the effect of a treatment, a sample is obtained from a population with a mean of μ = 20 and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M = 21.3 with a variance of s2 = 9. a. Assuming that the sample consists of n = 16 individuals, use a two-tailed test with α =0.05 to determine whether the treatment effect is significant and compute both Cohen's d and r2 to measure effect size. are the data sufficient to conclude that the treatment has a significant effect ? b. Assuming that the sample consists of n = 36 individuals, repeat the test and compute both measures of effect size? c. Comparing your answers for parts a and b, how does the size of the sample influence the outcome of a hypothesis test and the measurement of effect size?

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milcah answered 1 year ago

To evaluate the effect of a treatment, a sample is obtained from a population with an...

To evaluate the effect of a treatment, a sample is obtained from a population with an estimated mean of μ = 30, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be 32.5, with a standard deviation of s = 3. (5 points) Which statistical test is appropriate for this problem: one-sample t-test, repeated measures t-test, or independent samples t-test? If the sample consists of n = 16 individuals, are...

To evaluate the effect of a treatment, a sample of n = 6 is obtained from...

To evaluate the effect of a treatment, a sample of n = 6 is obtained from a population with a mean of μ = 80 and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M = 72. a. If the sample variance is s2 = 54, are the data sufficient to conclude that the treatment has a significant effect using a two-tailed test with α =0.05? b. If the...

1. To evaluate the effect of a treatment, a sample (n = 16) is obtained from...

1. To evaluate the effect of a treatment, a sample (n = 16) is obtained from a population with a mean of µ = 30 and a treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M = 31.3 with a sample standard deviation of s = 3. Are the data sufficient to conclude that the treatment has a significant effect using a two-tailed test with α = .05? Provide the...

Assume that the sample is a simple random sample obtained from a normally distributed population of...

Assume that the sample is a simple random sample obtained from a normally distributed population of IQ scores of statistics professors. Use the table below to find the minimum sample size needed to be 99% confident that the sample standard deviation s is within 1% of sigma. Is this sample size practical? sigma To be 95% confident that s is within 1% 5% 10% 20% 30% 40% 50% of the value of sigma, the sample size n should be at...

Assume that each sample is a simple random sample obtained from a population with a normal...

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A sample of n = 16 scores is obtained from a population with µ = 50...

A sample of n = 16 scores is obtained from a population with µ = 50 and σ = 16. If the sample mean is M = 58, then what is the z-score for the sample mean? z = - 2.00 z = +0.50 z = +2.00 z = +8.00 A researcher selects a random score from a normally distributed population. What is the probability that the score will be greater than z = +1.5 and less than z =...

A sample of n = 9 patients is obtained from a population with μ = 29,...

A sample of n = 9 patients is obtained from a population with μ = 29, and a treatment is administered to the individuals in the sample. After treatment, the sample mean X= 27. SS = 72. Compute one-sample t-value.

A sample of 16 individuals is selected from a population with μ = 75. A treatment...

A sample of 16 individuals is selected from a population with μ = 75. A treatment is administered to the sample. After treatment, M = 82 and s2 = 64. 1. Find the 90% confidence interval. 2. Find the 95% confidence interval. 3. What happens to the width of the interval when you increase the level of confidence (the percent confidence)? 4. Does the confidence interval always include the population mean, sample mean, or both?

A sample is selected from a population with µ= 50. After a treatment is administered to...

A sample is selected from a population with µ= 50. After a treatment is administered to the individuals in the sample, the mean is found to be M= 55 and the variance is s2= 64. For a sample of n = 16 scores, conduct a single sample t-test to evaluate the significance of the treatment effect and calculate Cohen’s d to measure the size of the treatment effect. Use a two-tailed test with α = .05. Show the sampling distribution....

a sample is selected from a population with u=50. after a treatment is administered to the...

a sample is selected from a population with u=50. after a treatment is administered to the individuals in the sample, the mean is found to be M=55 and the variance is s2 . equal 64. If the sample has n=4 scores , then conduct a hypothesis test to evaluate the significance of the treatment effect and calculate Cohen's d to measure the size of the treatment effect. Use a two-tailed test with alpha = .05 If the sample has n=16...

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