Research Scenario #1
A researcher hypothesizes that zylex, a new antidepressant, will affect concentration. It is known that scores on a standardized concentration test is normally distributed with a µ= 50 and a σ= 12. A random sample of n=16 participants, aged 19-35, are chosen from the State of New Jersey. The sample is put on a six month dosage plan of zylex. After six months, all the participants are given a standardized concentration test. The researcher records the data and calculates a sample mean of M=56. Are the data sufficient to conclude that the drug, zylex, does have an effect on concentration?
Based on the above research scenario, please answer the following questions:
I did step 1 but need step 2-4
Step 2:
Step 3:
Step 4: _______________________________
Write the statistical statement for your results: __________________________________
Interpret your results (relating back to the hypothesis): _______________________________________________________________________________________________________________________________________________________________________________________________________________________________________
If yes, what is the probability of a Type I error? ________
Is yes, how could you have decreased that probability? __________________________________
Is there a probability of Type II error? Yes_____ No______
If it is appropriate, please calculate effect size: Answer:_____________
Research Scenario #1 A researcher hypothesizes that zylex, a new antidepressant, will affect concentration. It is...
Research Scenario #2: A researcher wanted to study the effect of alcohol on reaction time. She hypothesized that alcohol will INCREASE reaction time (participants will take longer to react). She selected a sample of n= 36 participants from Rutgers University. The 36 participants each consumed a 6-ounce glass of wine. Thirty minutes later, the researcher measured each participant’s reaction time, using a standardized driving simulation task for which the regular population has a µ = 400 msec reaction time with...
A sleep researcher hypothesizes that sleep is related to
feelings of tiredness. Below are partial SPSS
results with α = 0.01 of the analysis for a sample of participants
at a sleep center.
a) Compute the appropriate test statistic(s) to
make a decision about H0.
(Hint: Make sure to write down the null and alternative hypotheses
to help solve the problem.)
Critical value = ; Test statistic =
Decision: ---Select--- Reject H0 Fail to reject H0
b) Compute the corresponding effect size(s)...
A sleep researcher hypothesizes that more sleep is related
feeling less tired. Below are partial SPSS results
with α = 0.01 of the analysis for a sample of participants at a
sleep center.
a) Compute the appropriate test statistic(s) to
make a decision about H0.
(Hint: Make sure to write down the null and alternative hypotheses
to help solve the problem.)
Critical value = ; Test statistic =
Decision: ---Select--- Reject H0 Fail to reject H0
b) Compute the corresponding effect size(s)...
A researcher administers a treatment to a sample of participants selected from a population with µ = 62. If the sample mean after the treatment is M = 70, which value of standard error,σM will result in the rejection of null hypothesis (assume p < 0.05, 2-tails test)? A. σM = 4 B. σM = 8 C. σM = 10 D. σM = 6 Please explain each step in detail, thank you!
Scenario 4. A researcher is interested in studying whether a new mobile app can help to reduce depression. She gives 14 participants the new app and measures their depression levels before using the app, and after using the app to see if depression levels change. Null hypothesis- H0: uposttest = upretest Alternative hypothesis- H1: uposttest ≠ upretest Independent variable- the phones the participants use Dependent variable- depression levels Using a dependent sample t-test 1) Imagine that you actually did the study...
A sleep researcher hypothesizes that more sleep is related feeling less tired. Below are partial SPSS results with α = 0.10 of the analysis for a sample of participants at a sleep center. Sleep Tired Sleep Pearson Correlation Sig. (2-tailed) N 1 13 0.804 −−− 13 Tired Pearson Correlation Sig. (2-tailed) N 0.804 −−− 13 1 13 a) Compute the appropriate test statistic(s) to make a decision about H0. (Hint: Make sure to write down the null and alternative hypotheses...
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...
give reason please
12. A research study uses a single sample of participants to evaluate the effect of a treatment. The results of the hypothesis test are reported as follows: (14)=2.73.p<.05." Based on this report, what was the statistical decision? (a) The null hypothesis was rejected and the probability of a Type I error is less than .05. b. The null hypothesis was not rejected and the probability of a Type I error is less than .05. e. The null...
A sleep researcher hypothesizes that sleep is related to feelings of tiredness. Below are partial SPSSresults with an α of 0.05 of the analysis for a sample of participants at a sleep center.SleepTiredSleepPearson Correlation Sig. (2-tailed) N1 130.804 −−− 13TiredPearson Correlation Sig. (2-tailed) N0.804 −−− 131 13a) Compute the appropriate test statistic(s) to make a decision about H0.(Hint: Make sure to write down the null and alternative hypotheses to help solve the problem.)Critical value = ; Test statistic = Decision: ---Select--- Reject H0 Fail to reject H0 b) Compute the corresponding effect size(s) and indicate magnitude(s).If not appropriate, input and/or select "na"...
, A researcher hypothesizes that arousal levels will be affected by meditation. The sample participates in formal meditation classes for 3 weeks, before and after which arousal is measured. Subject BEFORE MEDITATION AFTER MEDITATION 1 72 91 2 162 155 3 145 152 4 183 190 5 123 134 6 167 157 7 76 99 8 112 104 9 124 143 10 137 156 l. What is the researcher’s hypothesis? ________________________________________________________________________ 2. What is the null hypothesis? ________________________________________________________________________ 3. What...