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OpenStax-CNX module: m47494 1 Single Mean, Single Proportion Hypothesis Testing: Using Spreadsheets for Calculations and Display ∗ Irene Mary Duranczyk Suzanne Loch Janet Stottlemyer This work is produced by OpenStax-CNX and licensed under the † Creative Commons Attribution License 3.0 Abstract Basic directions on how to use Google Spreadsheet and Excel to calculate test results and display density curves. 1 Hypothesis Testing: Single Mean, Single Proportion using Spreadsheets In this section we will discuss techniques using spreadsheet for conducting an hypothesis test for one sample mean, population standard deviation known; a one sample mean, population standard deviation unknown: and for a one sample proportion, 1.1 Hypothesis Testing Formulas You can set up a worksheet in Excel to compute the one sample tests by using one of the following formulas in Excel or Google Spreadsheet ∗ Version 1.1: Aug 21, 2013 4:56 pm -0500 † http://creativecommons.org/licenses/by/3.0/ http://cnx.org/content/m47494/1.1/ OpenStax-CNX module: m47494 2 Function z-test: for population one Excel Formula Google Spreadsheet formula mean =z.test(array,x,sigma) where ar- =ztest(array,x,sigma) where ar- deviation ray is the sample data identify- ray is the sample data identify- ing the rst cell address and the ing the rst cell address and the last cell address in the data set, last cell address in the data set, x is the value you want to test, x is the value you want to test, and sigma is populations known and sigma is populations known standard deviation. standard deviation. sample standard known t-test: for a one sample mean population standard deviation =condence.t(alpha, standard No built in formula deviation, number in sample) unknown. z-test: one sample proportion There is no built in formula. . . we will calculate using model There is no built in formula. . . we will calculate using model below = p-hat±(critical value z- below = p-hat±(critical value z- score*sqrt((p-hat*(1-p-hat)/n) score*sqrt((p-hat*(1-p-hat)/n) Table 1 In an Excel or Google Spreadsheet you would arrange your data as demonstrated in the following columns. The following is labeled as though it was an Excel or Google Spreadsheet. Figure 1 http://cnx.org/content/m47494/1.1/ OpenStax-CNX module: m47494 3 Quantitative Data in Column A Figure 2 http://cnx.org/content/m47494/1.1/ OpenStax-CNX module: m47494 4 Figure 3 1.2 Displaying Condence Intervals: To graph T-test and Z-test use the Statistics Online Computational Resources (SOCR)(just as in the previous chapter)at http://socr.ucla.edu/htmls/SOCR_Distributions.html 1 has in the dropdown menu for SOCR distribution the normal distribution and for a Student's t-distribution. For a normal distribution, you will need to have your mean and standard deviation and again your right and left cut o values (which in this case will be your critical values). For a Student's t-distribution, you will need to have degrees of freedom and again your right and left cut o values (which in this case will be your critical values). Below is a graph of the Student's t-distribution. We have used the example from 8.6 Two column Model step by step example for this demonstration. The degrees of freedom were 14 and a 95% condence interval. We used the t-table to determine the left and right cut o values. In this instance two tailed condence interval of 95% with 14 degrees for freedom is minus and plus 2.145. 1 http://socr.ucla.edu/htmls/SOCR_Distributions.html http://cnx.org/content/m47494/1.1/ OpenStax-CNX module: m47494 5 Figure 4 This next example is using the normal distribution for determining the condence interval for a population proportion. The normal density curve here has the population proportion as the mean (p or p-hat) and the standard deviation (the square root of (p(1-p)/n). We have demonstrated the example 8.8 to show you how this looks in SOCR. For this problem the mean proportion was .842 and the critical z-value for a 95% condence interval was ± 0.032 or (0.81, 0.874). http://cnx.org/content/m47494/1.1/ OpenStax-CNX module: m47494 6 Figure 5 1.3 Optional Classroom Exercise: At your computer, try to use some of these tools to work out your homework problems or check homework that you have completed to see if the results are the same or similar. http://cnx.org/content/m47494/1.1/