In a condition of an experiment (based on a sample), a researcher obtains the following creativity scores:
3 2 1 0 7 4 8 6 6 4
In terms of creativity, interpret the variability of these data using the standard deviation.
Assume that the sample has an N of 1000. By making use of the method of standardization, about how many people would you expect to score below 1.59?
In a condition of an experiment (based on a sample), a researcher obtains the following creativity...
1. A researcher conducts an experiment comparing two treatment conditions and obtains data from 15 people for each treatment condition a. If the researcher used an independent-measures design, how many subjects altogether participated in the experiment? b. If the researcher used a repeated-measures design, how many subjects altogether participated in the experiment? c. If the researcher used a matched-subjects design, how many subjects altogether participated in the experiment?
In a cognitive psychology experiment, the researcher is interested in whether encoding condition has a significant effect on memory for a list of words. She recruits 32 subjects to participate in the experiment. Each recruited subject is randomly assigned to either encoding condition A or encoding condition B. The researcher would like to leave the hypothesis non-directional without predicting which encoding condition would lead to better memory, and she sets the significance level at α = .05 for a two-tailed...
A researcher in the field of educational psychology obtains a random sample of 49 fourth grade children and administers a conceptual problem-solving test to them. It is known that fourth graders have an average score of 82 on the test nationally. The children in this study score an average of 86, with a standard deviation of 5. Is the difference significant? What is the critical value (α = 0.05)? Select one: a. ±2.021 b. ±2.000 c. ±1.684 d. ±1.671 b....
The following 14 Questions (Q18- Q31) are based on the following example: A researcher want to determine whether high school students who attend an SAT prepared course score significantly different on an SAT than students who did not attend. For those who do not attend the course the population mean is 1050. The 16 students who attend the prep course average an 1200 on the SAT, with a sample standard deviation of 100. On the basis of this data, can...
1. A student was asked to compute the mean and standard deviation for the following sample of n= 5 scores: 81, 87, 89, 86, and 87. To simplify the arithmetic, the student first subtracted 80 points from each score to obtain a new sample consisting of 1,7,9,6, and 7. The mean and standard deviation for the new sample are then calculated to be M=6 and s = 3. What are the values of the mean and standard deviation for the...
1: Suppose that you take a random sample of 300 people and find that 102 of them say they prefer to buy organic food whenever possible, even if it’s more expensive. What is the sample proportion of people who prefer to buy organic? What is the standard deviation of the sample proportion? Calculate a 95% confidence interval for the population proportion. Do you reject the null hypothesis: p = 40%? Do you reject the null hypothesis p = 30%? 2:...
PLEASE help ??
A researcher conducted a single sample t-test on results of an experiment with n = 18 participants and the computed t = -2.28. What is the correct conclusion from this experiment if p < 0.05, 2-tails test is used for hypothesis testing? O A. The researcher failed to reject the null hypothesis and concluded that there is a significant treatment effect. O B. The researcher rejected the null hypothesis and concluded that there is a significant treatment...
6. "A researcher analyzed the results of an experiment and found that the obtained t-value (on a t-test of independent means) was 1.29, with a total of 25 children in group 1 and 30 children in group 2. Use a table of critical values and discuss whether the null hypothesis can or cannot be rejected. (Hint: Use Table 8.6 and 30 as the degree of freedom to support your decision.)" 14. For the following set of 10 scores, compute the...
A researcher wishes to determine if the use of iPads improves memory. Subjects will use the iPad regularly during a 10-week period of time. After this ten-week period, each subject has their memory tested using a standard memory test. Suppose the scores on this test of memory for all potential subjects using iPads follow a Normal distribution with mean μ and standard deviation σ = 6. Suppose also, that in the general population of all people, scores on the memory...
To evaluate the effect of a treatment, a sample of n-8 is obtained from a population with a mean of ?-50, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M 55. a) If the sample variance is s-32, use a two-tailed test with ?-0.05 to determine whether the treatment effect is significant and compute Cohen's d b) If the sample variance is s- 72, repeat the test and...