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Student's t-Test

Research Methods: Z test & One sample t-test questions

See attached file for proper format. WEB CALCULATOR EXERCISE 2 Z test & One sample t-test 1. A researcher is interested in whether students who attend private high schools have higher average SAT Scores than students in the general population. A random sample of 90 students at a private high school is tested and and a mea

Statistics: Calculate T value for salary levels for female and males HR managers

Using the raw measurement data presented below, calculate the t value for independent groups to determine whether or not there exists a statistically significant difference between the salaries of female and male human resource managers. Develop a research question, testable hypothesis, confidence level (i.e. set your alpha leve

Statistics psychological research question: z test, t test

Need help with one psychological research question that could be answered by each of the following types of statistical tests: a) Z test and T test for independent samples b) T test for dependent samples c) Rationale for both selections so I might be able to understand better

Important information about Two Sample T test

n = 17 M = 34.4 s = 4.0 n = 19 M = 31.9 s = 3.5 Use a single sample t test to determine whether sample 1 is significantly above the average of 30/kg/m2. One tailed test with a = .01 Also, What does this mean in words: t(18) = 4.00, p = .001, d = 1.79 When you have s (M1 - M2), does that mean the s

Experiment conducted to compare mean reaction time to two types of traffic signs.

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

T test for whether people make more money as they get older.

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.

Coaching company claims for raising SAT scores

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

Test claims at reasonable levels of significance for a new weight loss program

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

Hypothesis Test to determine difference in mean response

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

Paire t-test example

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

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?

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

Independent sample t test: Team A vs. B

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

AU Cellular: Create a hypothesis Test to compare to Softbank Cellular

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. -

T-Test for differences in groups investing in high interest savings accounts

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

Statistics: Hypothesis test for maintenance manager of new repair method

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

ANOVA & Tukey T- test

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

t-statistics with interpretation and assumptions

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

Test difference in mean battery life of two types of digital cameras

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

Statistics: Union membership, Free school lunches, Automobile parts production

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

Hypothesis Test

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

T Distribution, normal distribution, standard normal density curve

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

Independent Samples T-Test

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-Test for Hypothesis in EXCEL

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

Quality Motors: test hypothesis for consumer group's purpose, mean average MPG

See attached Excel file. Quality Motors is an automobile dealership that regularly advertises in its local market area. It claims that a certain make and model of car averages 30 miles to a gallon of gas and mentions that this figure may vary with driving conditions. A local consumer group wishes to verify the advertising cla