T-Tests and Data Collection
What sort of data must you collect to conduct a t-test? Why?
What sort of data must you collect to conduct a t-test? Why?
An experiment was conducted to compare mean reaction time to 2 types of traffic signs, prohibitive (No Left Turn) and permissive (Left Turn Only). Ten subjects were included in the experiment. Each subject was presented with 40traffice signs: 10 prohibitive and 10 permissive in random order. The mean time to reaction and the num
Please see attached file and and answer the questions and include an explanation. State insured uninsured unknown total Nebraska 800,000 12,000 100 812,100 Arizona 2,000,000 800,000 1,000,000 3,800,000 Oregon 2,000,000 50,000 100,000 2,150,000 New York 8,000,000 2,000,000 5,000,000 15,000,000 total 12,800,000 2,862,000 6
Complete a T-test for the following data: Use Excel. Do people, regardless of individual issues, in general make more money as they get older? Below is a data list. The random error for this test comes from the fact that salary can have a variety of ranges based on type of occupation, personal ability, plus many other items.
Time (minutes per day) spent in 3 different postures by lean and obese subjects: Group Subject Stand/walk Sit Lie _____________________________________________________________ Lean 1 511.100 370.300 555.500 Lean 2
Coaching compaines claim that their courses can raise the SAT scores of high school students. Of course, students who retake the SAT without paying for coaching generally raise their scores. A random sample of students who took the SAT twice found 427 who were coached and 2733 who were uncoached. Starting with their verbal sc
Suppose a new weight loss program was sponsored by the local health and fitness club in a small town. The program claims to make people lose more than five pounds in a month. Twelve participants were selected and their weights were recorded. After a month of the program their weights were recorded again. It was found that many
Markowitz and Felson (1998) examined how attitudes toward violence may differ between the general population and ex-offenders. This question is based on their paper. The authors asked both samples to indicate whether they strongly agreed (-2), agreed (-1), were not sure (0), disagreed (+1), or strongly disagreed (+2) with the fo
Community policing strategies have been useful in some jurisdictions to reduce crime. As Police Captain, you wish to run an experiment to see whether it will work in your city. In each of 10 neighborhoods you record the number of arrests for violent offenses for 90 days prior to implementing a community policing strategy and for
In this activity, we will start with the data file used in Part A ('Activity 5a.sav'). Suppose, however, you [the researcher] encountered a small problem during data collection: after the post-tests were collected, you realized that the post-test form did not ask for the students' identification number. As such, it will be impos
An average computer mouse inspector can inspect 50 mice per hour. The 48 computer mice inspectors at a particular factory can only inspect 46 mice per hour with a standard deviation of 10. At = 0.025, does the company have reason to believe that these inspectors are slower than average? A doctor believes that the standard d
Use these parameters to solve and compare. Team A vs B Total of 10 A and 10 B Results of Team A: 7, 8, 5, 2, 3, 9, 6, 6, 7, 9 Team B: 2, 4, 4, 1, 2, 9, 3, 3, 5, 2 (better team) - Show formula used and walk through the steps. - State the hypotheses and identify the claim - Find the critical values - Compute the
Using Activity_7.sav, (a) perform exploratory data analysis on CreativityPre and CreativityPost. Using SPSS, calculate the mean and standard deviation of these two variables. (b) perform a dependent (paired-samples) t-test with CreativityPre and CreativityPost. (c) Construct an appropriate chart/graph that displays the rele
AU Cellular believes their sales are more consistent than their rival Softbank Cellular. Below is the number lost calls a day over the last seven days. Do you agree with AU? Use the .01 significance level. Softbank, 78, 98, 54, 57, 68, 64, 70 AU, 75, 81, 81, 40, 82, 75, 35 - Show formua used and walk through the steps. -
Group Statistics   Group N Mean Std. Deviation Std. Error Mean Annual Income Control Group 42 20813.7143 10578.81613 1632.34677 Experiment Group 42 22258.7619 8896.90632 1372.82245 Independent Samples Test   Levene's Test for Equality of Variances t-test for Equality of Means F Sig. t df Sig. (2-tailed) Mean Diff
Twenty students randomly assigned to an experimental group receive an instructional program; 30 in a control group do not. After 6 months, both groups are tested on their knowledge. The experimental group has a mean of 38 on the test (with an estimated population standard deviation of 3); the control group has a mean of 35 (
A maintenance manager must test a new repair method that should increase the expected time between repairs. For each machine used in the study, she recorded the last time between failures prior to using the new method, which she called "Current," and the first time between failures after using the new, which she called "New." Th
See attached file. Interpret analysis using Tukey test on Question #5 Test Message cell D and Question # 8 Internet cell 0 with Question #8 E- mail cell P What is the correct decision process using relative to the null
Why is a t-statistic, as opposed to a z-statistic, used to test small populations? When does the t-statistic approximate the z-statistic?
Consider the filling operation for 20-oz bottles of a popular soft drink. Historically, this operation averages 20.2 oz. A recent random sample of 12 bottles yielded these volumes: 20.0 20.1 20.0 19.9 20.5 20.9 20.1 20.4 20.2 19.1 20.1 20.0 a. Find the sample mean for these data. b. Assume that the historical av
Q-5a. One of the important features of a camera is the battery life as measured by the number of shots taken until the battery needs to be recharged. The data below contain the battery life of 31 subcompact cameras and 15 compact cameras. Assuming that the population variances from both types of digital cameras are equal, is
If a researcher were studying the effects of a teaching method on patient learning outcomes, how must he or she word the research question to use a t-test to test for statistical differences? What type of data must he or she collect? Why?
1. Union Membership Nationwide 13.7% of employed wage and salary workers are union members (down from 20.1% in 1983). A random sample of 300 local wage and salary workers showed that 50 belonged to a union. At ?=0.05, is there sufficient evidence to conclude that the proportion of union membership differs from 13.7%? 2. F
In a paragraph explain the differences between the Independent Samples and Paired Samples T-Test. When do you use each? Purport a research question that could be addressed using each test
See attached file. Using AIU's survey responses from the AIU data set,complete the following requirements in the form of a report: 1. Perform a two-tailed hypothesis test on both the intrinsic and the extrinsic variable's data, using a .05 significance level. 2. Begin by creating a null and an alternate statement. 3. Us
A United Nations report shows the mean family income for Mexican migrants to the United States is $27,150 per year. A FLOC (Farm Labor Organizing Committee) evaluation of 30 Mexican family units reveals a mean to be $29,500 with a sample standard deviation of $11,150. Does this information disagree with the United Nations report
Question 6 Consider a t distribution with 26 degrees of freedom. Compute P (-1.2 < t < 1.2). Round your answer to at least three decimal places. Consider a t distribution with 19 degrees of freedom. Find the value of c such that P (t <=c) = 0.05. Round your answer to at least three decimal places. Below is a graph of a
I have provided an independent T-test analysis for you on the difference between mathematics standardized scores for a small sample of students in Veracruz, Mexico given their vision as either blurry or ok. Are the average scores different? At what level of significance? Is it what you would expect? What could account for this
t-tests On the attached excel file are data on cancer rates by region for the whole of Scotland. The data were collected in 2000 and are expressed as rates per 100,000. If you were to compare the statistical likelihood of a man or a woman contracting lung cancer using a t-test Excel would produce the following output. t-Te
13. To evaluate the effect of a treatment, a sample of n = 9 is obtained from a population with a mean of µ = 40, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to be M = 33. a. If the sample has a standard deviation of s = 9, are the data sufficient to conclude