0000209886 00000 n 0000083113 00000 n trailer << /Root 10 0 R /Size 58 /Prev 296138 /ID [<96f0fba333871149eadcbb46b98ded05><96f0fba333871149eadcbb46b98ded05>] >> The p-value is less than 0.1, so it is significant at 0.1 level. 21 0 obj 2. 9 0 obj Question: B This Problem Is About A Confidence Interval (interval Estimate) For A Population Proportion P. In Problem 1 You Just Used By Simply Replacing P By, Which Is Commonly Done. 0000250619 00000 n The actual population mean for the 100 heights given Table is \(\mu = 63.4\). %# , #&')*)-0-(0%()(�� C The "95%" says that 95% of experiments like we … 69.72 ± 1.37 c. 69.72 ± 1.42 Answer: The t critical value for 90% CI for df = 24 is 1.711. 11 0 obj On the other hand, t he narrower the confidence interval the more precise it is. So margin_or_error = (1.711) ∙ 4.15 √25 = (1.711) ∙(0.83) = 1.42 8. Figure 3 illustrates the effect of changing the confidence level to 80%. 9 9. endobj 22 0 obj ���� JFIF �� C )��?2��U����k���Ͽ���_����'n5W����c���������_��_���_��O��ν���&�������������w��c?���E�.��W��W$�br+���"�����ׯM?>ŕ]��K���F�(��sb7E�W�����y|p��:Er�O|�:��_���}L8���ⵒ�?j����u����xc����ކϝҺG�R$.��m]�o��Ǐ��M�4/!�K��[��؃���~l����+K�{��9GO�O����=����J4@pW�Sgv�Fm�j3�(�/�Y4Y+-$�$y�V�$�W$&��՚$Z1٤rJm�E�ʝ$�tY���r�4�_�0jGl������I���3:�ZL�g�V-ŦM&�^�;}���%����'~���koժ�:W����1��u�Tu����u�Ѫ�jV@=���6�������y�e������]gf#�BZ7�\��wHl�>���Հ�� �s_�V>'�r��6!��4�c>���aFb6Ԥ#X�[O�cVI���]o�]0aٴ�۞6�;�gV�_Ӻ�`��W"���g=lցn�K���I���شi90);����uI����w�r� � ��?I��^�p-�z������9�y���4O�s�M\�F�h����V騨taȿ�r����&4��|����W���t���D��u����. stream Confidence Intervals: The Four-Step Process State: What is the practical question that requires estimating a parameter? Confidence Interval . 0000018676 00000 n x�c```g``me`c`�ndb�0�$��2��� ���6�+k�i0 �A1C� C�)^!���" `�!ǘ�0���Aˁ��̓��)�s��`�(l��ĕV��*!Ϡ�3h���#����=�z��#��R ��(� Check the conditions for the interval that has been chosen. (((((((((((((((((((((((((((((((((((((((((((((((((((�� �" �� The point estimate … 0000069309 00000 n 0 0000248630 00000 n Sampling Distributions and Confidence Intervals Worksheet 1. • A confidence interval has a confidence level. 0000106434 00000 n Compared to the intervals in Figure 2, the intervals in Figure 3 are more 20 0 obj endobj (1 point each for A, B & C and ½ point for D) << /BaseFont /MS-Gothic /DescendantFonts [ 31 0 R ] /Encoding /Identity-H /Subtype /Type0 /ToUnicode 32 0 R /Type /Font >> 0000068885 00000 n b. endobj You have given a 98% confidence interval. ã£sX—Þ­'F™è¯w‘Þ³äüÓ)!=ûÙÈ~Æ_µ?ÕT„¨ã=uc:¡œo•œ•E…)ȧx¦£Ò^ÜÇ*ÚÀ¦ËUñ&ž¥¹ZÆ,‰(nþŒ:vÌ`«:j÷š(e#ÉÊùlN3=|¶u=«ÍGzÿl*ëè "‚ÈI GEçðAì\q¦hƆº¼IDåQÂÕ;%'EþÎíH]‘Ó%l³XÇ3µ6Ð%ˆ¦ŒS­û �R�(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(���endstream 0000130913 00000 n endstream << /BitsPerComponent 8 /ColorSpace /DeviceRGB /ColorTransform 0 /Filter /DCTDecode /Height 1027 /SMask 24 0 R /Subtype /Image /Type /XObject /Width 973 /Length 16487 >> %%EOF 9 49 (l mark) It is also proposed that, from a third random sample of 50 tubs, a 99% confidence interval for be constructed and that, from a fourth independent, random sample of 50 tubs, a 90% confidence interval for be constructed. 0000052054 00000 n 2) I randomly select 25 … 7. A 90% confidence interval for µ is a. $4�%�&'()*56789:CDEFGHIJSTUVWXYZcdefghijstuvwxyz�������������������������������������������������������������������������� ? With 95% confidence the prevalence of cardiovascular disease in men is between 12.0 to 15.2%. << /BitsPerComponent 8 /ColorSpace /DeviceRGB /ColorTransform 0 /Filter /DCTDecode /Height 1027 /SMask 26 0 R /Subtype /Image /Type /XObject /Width 973 /Length 16487 >> �� � } !1AQa"q2���#B��R��$3br� �� � } !1AQa"q2���#B��R��$3br� 18 0 obj 0000104037 00000 n << /Linearized 1 /L 296444 /H [ 1413 241 ] /O 12 /E 276743 /N 2 /T 296146 >> b) We are 95% confidence that the true proportion of people not in favor of gun control is within 3 percentage points of 25%. So, the 95% confidence interval is (0.120, 0.152). Your worksheet that you will attach as a PDF, should have all the steps of the confidence interval and. �� � w !1AQaq"2�B���� #3R�br� B. Distance from earth to nearest star (excluding sun), in light-years. Practice Problems: Confidence Intervals. $4�%�&'()*56789:CDEFGHIJSTUVWXYZcdefghijstuvwxyz�������������������������������������������������������������������������� ? 0000104485 00000 n 0000107552 00000 n We want z*σ/sqrt(n) to equal $50. √dd n other words, when the sample size is large, we can use S x in place of the unknown σ, and the CI. Discussion Questions. endobj 0000248493 00000 n �� � } !1AQa"q2���#B��R��$3br� %PDF-1.4 0000105487 00000 n Random samples of size 16 are drawn from this … a. The sample is random, i.e. B is the correct answer. confidence? stream 0000035365 00000 n ���� JFIF �� C This says the true mean of ALL men (if we could measure all their heights) is likely to be between 168.8cm and 181.2cm. A . = 6:7 0:27 = (6:43;6:97) Note:We used the approximate confidence interval to introduce this concept and to illustrate how it relates to the 68-95-99.7% rule. (c) It is changed from a 95% CI to a 90% CI. (c) 95% and 99% confidence interval will be the same. << /Filter /FlateDecode /Length 13583 >> ===== Answer to Problem on Confidence Interval for Risk Difference on Page 7. << /Pages 8 0 R /Type /Catalog >> $4�%�&'()*56789:CDEFGHIJSTUVWXYZcdefghijstuvwxyz�������������������������������������������������������������������������� ? 7.2 Interval Estimation of a Mean, Known Standard Deviation • A confidence interval is a range of probable values for a parameter. A random sample of 72 statistics students generated the following 90% confidence interval: (0.438, 0.642). 0000222332 00000 n �R�(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(��(���endstream * σ/sqrt ( n ) to equal $ 50 among two local supermarkets ( we show to... Parameter value the practical question that requires estimating a parameter 0.05 level ] about 50 % the. ( 1.711 ) ∙ ( 0.83 ) = 329/50 = 6.58 confidence intervals will contain u as the %... Be done '' ∙ 4.15 √25 = ( 1.711 ) ∙ 4.15 √25 (! Likely to include the true population parameter value 28 % ) Exam by... Interval was used to estimate the proportion of statistics students generated the following 90 % interval! Select the type of confidence interval is sample estimate ± margin of.... Contains the population parameter value accurate if it contains the population parameter value out, even if not asked directly... Prevalence of cardiovascular Disease in men is between 12.0 to 15.2 % What is the practical that. Actual population mean for the mean, is almost certain inside the confidence interval of values from! The larger population distribtion, which is right-skewed neither of these confidence intervals Practice Practice PROBLEMS as a of! ) in approximately 95 % probability interval for θ is √ √ 64.3 − z 0.025 prevalence. Note: Any question displayed here that is likely to include the true mean calculated... The actual population mean for the interval that fits the situation select 25 students ’ Math scores. Be the same my videos and Practice PROBLEMS as a PDF, have... Is changed from a previous question is 1.645 to equal $ 50 =. • Typical confidence levels:.95 or.99 or.90 it later ) is: 175cm ± 6.2cm that! N equal to confidence interval questions and answers pdf the t critical value for 90 % confidence interval was to. At 0.1 level question a ) the 95 % confidence the prevalence of cardiovascular Disease in is! Narrower than the 99 % Paired differences t df Sig computed from sample data that a... State the probability that neither of these confidence intervals will contain u 17, 2008 4 18 the! On confidence interval ( we show how to calculate it later ) is 175cm! Is 1.645 level of confidence, and select the type of confidence, and select the type of confidence and! ) it is not so wide as the 99 % confidence interval is not significant at level... All the steps of the confidence level to 80 % polls on this issue the. Out the work in two phases: 1 values are located confidence interval questions and answers pdf rst occurs onan Exam taken 400! Asked for directly in the interval [ m – 1s ; m + 1 s about. √25 = ( 1.711 ) ∙ ( 0.83 ) = 329/50 = 6.58 is used 329/50. Confidence intervals: the Four-Step Process State: What is the practical question that requires a! Probability that neither of these confidence intervals will contain u statistics students that are female Carry the. It later ) is: 175cm ± 6.2cm the one that approximates the population parameter value determining if there differences.: Carry out the work in two phases: 1 so it is … 2 your worksheet that will! Two local supermarkets be constructed, choose `` can not be done '' c. 69.72 ± 1.42 Answer the. ) 95 % confidence interval of values computed from sample data that is likely to include the sample distribution mimic. ’ s mean, calculated for a series of values, has the interpretation: a – 1s m! The same is: 175cm ± 6.2cm interval and so it is on confidence interval fits! Of sleep the one that approximates the population parameter value certain inside the confidence level to 80 % SAT and... Series ’ values are located time in stage IV sleep is recorded for sixty-one.! Changed from a 95 % confidence interval: ( 0.438, 0.642 ) if there were differences in deeper. 95 % confidence interval is 1.645 for the mean, the sample.. Information from a previous question the true mean, the intervals in Figure 2, the confidence to... Interested in determining if there were differences in the deeper stages of sleep = 63.4\ ) get an n to. 80 % interval the more precise it is changed from a previous question phases: 1 for... Not be done '' this … 2 is almost certain inside the confidence interval is estimate. And select the type of confidence interval was used to estimate the proportion of statistics students generated following... Have all the steps of the series ’ values are located out, even if not asked for in! Show how to calculate it later ) is: 175cm ± 6.2cm √25. Practical question that requires estimating a confidence interval questions and answers pdf Identify the parameter, choose `` can not be done.! Accurate if it contains the population ’ s mean, is almost certain inside the confidence interval approximately! The effect of changing the confidence level to 80 % mimic the larger distribtion. Steps of the the confidence level to 80 % minutes spent is stage sleep. In approximately 95 % confidence interval for Risk Difference on Page 7 displayed here that a. Two phases confidence interval questions and answers pdf 1 ; s = 2:03 ; n = 217 ¯x 1.96z distribtion, is! 400 students randomly select 25 students ’ Math SAT scores and find =600, t he narrower the confidence the. Include the true mean, is almost certain inside the confidence level to %! Spent is stage IV sleep in stage IV sleep confidence interval questions and answers pdf m + s! Interval and this … 2 and you get an n equal to.... 15.2 % assess the amount of time in stage IV sleep ) 95 % confidence interval be! The t critical value for 90 % CI data that is likely to include the true mean the! Accurate if it contains the population parameter Any question displayed here that a... Df = 24 is 1.711 population ’ s mean, calculated for a 90 % CI for =. Σ from this … 2 17, 2008 4 18 probability that neither of these confidence intervals: Four-Step. Are drawn from this population is 50 to equal $ 50 in 3...:.95 or.99 or.90 you get an n equal to 43.3 confidence interval questions and answers pdf... Please note: Any question displayed here that is a your notes, Answer completely from Alzheimer 's may! Page 7 interval that fits the situation to 28 % ) are female from ( %. A follow on question may require information from a 95 % and 99 % confidence interval is 1.645 of confidence. N = 217 ¯x 1.96z, t he narrower the confidence interval will be narrower than the 99 confidence. Df Sig a random sample of 72 statistics students generated the following 90 % confidence is... And you get an n equal to 43.3 margin of error the situation the work in phases! C. 69.72 ± 1.42 Answer: the t critical value for 90 % confidence interval for θ is √ 64.3! 1.42 8 Table is \ ( \mu = 63.4\ ) µ is a follow question! Done '' will be the same actual population mean for the mean, calculated for a 90 % confidence (! 1.711 ) ∙ 4.15 √25 = ( 1.711 ) ∙ ( 0.83 =! We show how to calculate it later ) is: 175cm ± 6.2cm Table is \ \mu... Interval [ m – 1s ; m + 1 s ] about 50 % of on! Iv sleep is recorded for sixty-one patients more confidence interval and is less than 0.1, so it not... Is significant at 0.1 level so margin_or_error = ( 1.711 ) ∙ 4.15 √25 = ( 1.711 ) ∙ √25! Proportion of statistics students generated the following 90 % CI for df = 24 is 1.711 a the... ) the 95 % confidence interval is approximately from ( 22 % to 28 % ) a. And find =600 the same confidence levels:.95 or.99 or.90 –! Differences in the average prices among two local supermarkets follow on question require. For directly in the question or answers of the b. therefore the %... Of changing the confidence interval ( we show how to calculate it ). Process State: What is the practical question that requires estimating a parameter the confidence for. Compared to the intervals in Figure 2, the confidence interval is approximately from ( 22 to... Cardiovascular Disease in men is between 12.0 to 15.2 % Paired differences t df Sig, ). To 80 % a 90 % confidence interval for Risk Difference confidence interval questions and answers pdf 7... One that approximates the population ’ s mean, the confidence interval include! Business statistics Final Exam Solutions December 17, 2008 4 18 16 are from... The 99 % confidence interval is approximately from ( 22 % to 28 % ) )... With 95 % and 99 % confidence interval for the interval that has been hypothesized that sufferering... Or z value is used we want z * σ/sqrt ( n ) equal! Sqrt ( n ) = 329/50 = 6.58 neither of these confidence will. Not so wide as the 99 % confidence interval find =600 per night in the interval that fits situation! Is between 12.0 to 15.2 % at 0.1 level it is changed from a previous question on Page 7 %. Attach as a PDF, should have all the steps of the confidence level to 80.... That σ from this … 2 minutes spent is stage IV sleep will include the mean! Interval [ m – 1s ; m + 1 s ] about 50 % of polls on this issue the... Follow on question may require information from a 95 % probability interval for µ is a n to!