Chapter 2

Psychological Research

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2.3 Analyzing Findings

Learning Objectives

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CORRELATIONAL RESEARCHCorrelation JB>KP QE>Q QEBOB FP > OBI>QFLKPEFM ?BQTBBK QTL LO JLOB S>OF>?IBP PR@E >P F@B @OB>J@LKPRJMQFLK >KA @OFJB ?RQ QEFP OBI>QFLKPEFM ALBP KLQ KB@BPP>OFIV FJMIV @>RPB >KA BCCB@Q� 7EBK QTLS>OF>?IBP >OB @LOOBI>QBA FQ PFJMIV JB>KP QE>Q >P LKB S>OF>?IB @E>KDBP PL ALBP QEB LQEBO� 7B @>K JB>PROB@LOOBI>QFLK ?V @>I@RI>QFKD > PQ>QFPQF@ HKLTK >P > @LOOBI>QFLK @LBCCF@FBKQ� ! correlation coefficient FP >KRJ?BO COLJ �� QL �� QE>Q FKAF@>QBP QEB PQOBKDQE >KA AFOB@QFLK LC QEB OBI>QFLKPEFM ?BQTBBK S>OF>?IBP� 4EB@LOOBI>QFLK�@LBCCF@FBKQ�FP�RPR>IIV�OBMOBPBKQBA�?V�QEB�IBQQBO r�

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LINK TO LEARNING

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archival research

attrition

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clinical or case study

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confounding variable

control group

correlation

correlation coefficient

cross-sectional research

debriefing

deception

deductive reasoning

dependent variable

double-blind study

empirical

experimental group

experimenter bias

fact

falsifiable

Key Terms

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generalize

hypothesis

illusory correlation

independent variable

inductive reasoning

informed consent

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Institutional Review Board (IRB)

inter-rater reliability

longitudinal research

naturalistic observation

negative correlation

observer bias

operational definition

opinion

participants

peer-reviewed journal article

placebo effect

population

positive correlation

random assignment

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4EFP�@LKQBKQ�FP�>S>FI>?IB�CLO�COBB�>Q�

random sample

reliability

replicate

sample

single-blind study

statistical analysis

survey

theory

validity

PR?PBQ�LC�>�I>ODBO�MLMRI>QFLK�FK�TEF@E�BSBOV�JBJ?BO�LC�QEB�MLMRI>QFLK�E>P�>K�BNR>I@E>K@B�LC�?BFKD�PBIB@QBA

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PR?PBQ�LC�FKAFSFAR>IP�PBIB@QBA�COLJ�QEB�I>ODBO�MLMRI>QFLK

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Summary

2.1 Why Is Research Important?3@FBKQFPQP >OB BKD>DBA FK BUMI>FKFKD >KA RKABOPQ>KAFKD ELT QEB TLOIA >OLRKA QEBJ TLOHP >KA QEBV >OB>?IB QL AL PL ?V @LJFKD RM TFQE QEBLOFBP QE>Q DBKBO>QB EVMLQEBPBP QE>Q >OB QBPQ>?IB >KA C>IPFCF>?IB� 4EBLOFBPQE>Q PQ>KA RM QL QEBFO QBPQP >OB OBQ>FKBA >KA OBCFKBA TEFIB QELPB QE>Q AL KLQ >OB AFP@>OABA LO JLAFCFBA�)K QEFP T>V OBPB>O@E BK>?IBP P@FBKQFPQP QL PBM>O>QB C>@Q COLJ PFJMIB LMFKFLK� (>SFKD DLLA FKCLOJ>QFLKDBKBO>QBA�COLJ�OBPB>O@E�>FAP�FK�J>HFKD�TFPB�AB@FPFLKP�?LQE�FK�MR?IF@�MLIF@V�>KA�FK�LRO�MBOPLK>I�IFSBP�

2.2 Approaches to Research4EB @IFKF@>I LO @>PB PQRAV FKSLISBP PQRAVFKD GRPQ > CBT FKAFSFAR>IP CLO >K BUQBKABA MBOFLA LC QFJB� 7EFIBQEFP >MMOL>@E MOLSFABP >K FK@OBAF?IB ABMQE LC FKCLOJ>QFLK QEB >?FIFQV QL DBKBO>IFWB QEBPB L?PBOS>QFLKP QLQEB I>ODBO MLMRI>QFLK FP MOL?IBJ>QF@� .>QRO>IFPQF@ L?PBOS>QFLK FKSLISBP L?PBOSFKD ?BE>SFLO FK > K>QRO>IPBQQFKD >KA >IILTP CLO QEB @LIIB@QFLK LC S>IFA QORB�QL�IFCB FKCLOJ>QFLK COLJ OB>IFPQF@ PFQR>QFLKP� (LTBSBO K>QRO>IFPQF@ L?PBOS>QFLK ALBP KLQ >IILT CLO JR@E @LKQOLI >KA LCQBK OBNRFOBP NRFQB > ?FQ LC QFJB >KA JLKBVQL MBOCLOJ� 2BPB>O@EBOP PQOFSB QL BKPROB QE>Q QEBFO QLLIP CLO @LIIB@QFKD A>Q> >OB ?LQE OBIF>?IB @LKPFPQBKQ >KAOBMIF@>?IB�>KA�S>IFA�>@@RO>QB�

3ROSBVP @>K ?B >AJFKFPQBOBA FK > KRJ?BO LC T>VP >KA J>HB FQ MLPPF?IB QL @LIIB@Q I>ODB >JLRKQP LC A>Q>NRF@HIV� (LTBSBO QEB ABMQE LC FKCLOJ>QFLK QE>Q @>K ?B @LIIB@QBA QEOLRDE PROSBVP FP PLJBTE>Q IFJFQBA@LJM>OBA�QL�>�@IFKF@>I�LO�@>PB�PQRAV�

!O@EFS>I�OBPB>O@E�FKSLISBP�PQRAVFKD�BUFPQFKD�A>Q>�PBQP�QL�>KPTBO�OBPB>O@E�NRBPQFLKP�

,LKDFQRAFK>I OBPB>O@E E>P ?BBK FK@OBAF?IV EBIMCRI QL OBPB>O@EBOP TEL KBBA QL @LIIB@Q A>Q> LK ELT MBLMIB@E>KDB�LSBO�QFJB��#OLPP�PB@QFLK>I�OBPB>O@E�@LJM>OBP�JRIQFMIB�PBDJBKQP�LC�>�MLMRI>QFLK�>Q�>�PFKDIB�QFJB�

2.3 Analyzing Findings! @LOOBI>QFLK FP ABP@OF?BA TFQE > @LOOBI>QFLK @LBCCF@FBKQ r TEF@E O>KDBP COLJ �� QL �� 4EB @LOOBI>QFLK@LBCCF@FBKQ QBIIP RP >?LRQ QEB K>QROB MLPFQFSB LO KBD>QFSB >KA QEB PQOBKDQE LC QEB OBI>QFLKPEFM ?BQTBBKQTL LO JLOB S>OF>?IBP� #LOOBI>QFLKP AL KLQ QBII RP >KVQEFKD >?LRQ @>RP>QFLKoOBD>OAIBPP LC ELT PQOLKDQEB OBI>QFLKPEFM FP ?BQTBBK S>OF>?IBP� )K C>@Q QEB LKIV T>V QL ABJLKPQO>QB @>RP>QFLK FP ?V @LKAR@QFKD >KBUMBOFJBKQ��0BLMIB�LCQBK�J>HB�QEB�JFPQ>HB�LC�@I>FJFKD�QE>Q�@LOOBI>QFLKP�BUFPQ�TEBK�QEBV�OB>IIV�AL�KLQ�

#E>MQBO���0PV@ELILDF@>I�2BPB>O@E ��

2BPB>O@EBOP @>K QBPQ @>RPB�>KA�BCCB@Q EVMLQEBPBP ?V @LKAR@QFKD BUMBOFJBKQP� )AB>IIV BUMBOFJBKQ>IM>OQF@FM>KQP >OB O>KALJIV PBIB@QBA COLJ QEB MLMRI>QFLK LC FKQBOBPQ� 4EBK QEB M>OQF@FM>KQP >OB O>KALJIV>PPFDKBA QL QEBFO OBPMB@QFSB DOLRMP� 3LJBQFJBP QEB OBPB>O@EBO >KA QEB M>OQF@FM>KQP >OB ?IFKA QL DOLRMJBJ?BOPEFM�QL�MOBSBKQ�QEBFO�BUMB@Q>QFLKP�COLJ�FKCIRBK@FKD�QEB�OBPRIQP�

)K FAB>I BUMBOFJBKQ>I ABPFDK QEB LKIV AFCCBOBK@B ?BQTBBK QEB BUMBOFJBKQ>I >KA @LKQOLI DOLRMP FP TEBQEBOM>OQF@FM>KQP >OB BUMLPBA QL QEB BUMBOFJBKQ>I J>KFMRI>QFLK� %>@E DOLRM DLBP QEOLRDE >II ME>PBP LC QEBBUMBOFJBKQ ?RQ B>@E DOLRM TFII BUMBOFBK@B > AFCCBOBKQ IBSBI LC QEB FKABMBKABKQ S>OF>?IB� QEB BUMBOFJBKQ>IDOLRM FP BUMLPBA QL QEB BUMBOFJBKQ>I J>KFMRI>QFLK >KA QEB @LKQOLI DOLRM FP KLQ BUMLPBA QL QEBBUMBOFJBKQ>I J>KFMRI>QFLK� 4EB OBPB>O@EBO QEBK JB>PROBP QEB @E>KDBP QE>Q >OB MOLAR@BA FK QEB ABMBKABKQS>OF>?IB FK B>@E DOLRM� /K@B A>Q> FP @LIIB@QBA COLJ ?LQE DOLRMP FQ FP >K>IVWBA PQ>QFPQF@>IIV QL ABQBOJFKB FCQEBOB�>OB�JB>KFKDCRI�AFCCBOBK@BP�?BQTBBK�QEB�DOLRMP�

0PV@ELILDFPQP OBMLOQ QEBFO OBPB>O@E CFKAFKDP FK MBBO�OBSFBTBA GLROK>I >OQF@IBP� 2BPB>O@E MR?IFPEBA FK QEFPCLOJ>Q FP @EB@HBA ?V PBSBO>I LQEBO MPV@ELILDFPQP TEL PBOSB >P > CFIQBO PBM>O>QFKD FAB>P QE>Q >OB PRMMLOQBA?V BSFABK@B COLJ FAB>P QE>Q >OB KLQ� 2BMIF@>QFLK E>P >K FJMLOQ>KQ OLIB FK BKPROFKD QEB IBDFQFJ>@V LCMR?IFPEBA OBPB>O@E� )K QEB ILKD ORK LKIV QELPB CFKAFKDP QE>Q >OB @>M>?IB LC ?BFKD OBMIF@>QBA @LKPFPQBKQIVTFII�>@EFBSB�@LKPBKPRP�FK�QEB�P@FBKQFCF@�@LJJRKFQV�

2.4 Ethics%QEF@P FK OBPB>O@E FP >K BSLISFKD CFBIA >KA PLJB MO>@QF@BP QE>Q TBOB >@@BMQBA LO QLIBO>QBA FK QEB M>PQTLRIA ?B @LKPFABOBA RKBQEF@>I QLA>V� 2BPB>O@EBOP >OB BUMB@QBA QL >AEBOB QL ?>PF@ BQEF@>I DRFABIFKBP TEBK@LKAR@QFKD BUMBOFJBKQP QE>Q FKSLISB ERJ>K M>OQF@FM>KQP� !KV BUMBOFJBKQ FKSLISFKD ERJ>K M>OQF@FM>KQPJRPQ ?B >MMOLSBA ?V >K )2"� 0>OQF@FM>QFLK FK BUMBOFJBKQP FP SLIRKQ>OV >KA OBNRFOBP FKCLOJBA @LKPBKQ LCQEB M>OQF@FM>KQP� )C >KV AB@BMQFLK FP FKSLISBA FK QEB BUMBOFJBKQ B>@E M>OQF@FM>KQ JRPQ ?B CRIIV AB?OFBCBARMLK�QEB�@LK@IRPFLK�LC�QEB�PQRAV�

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Review Questions

1. 3@FBKQFCF@�EVMLQEBPBP�>OB�========�>KAC>IPFCF>?IB�

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15. 7EF@E�PQ>QBJBKQ�?BPQ�FIIRPQO>QBP�>�KBD>QFSB@LOOBI>QFLK�?BQTBBK�QEB�KRJ?BO�LC�ELROP�PMBKQT>Q@EFKD�46�QEB�TBBH�?BCLOB�>K�BU>J�>KA�QEBDO>AB�LK�QE>Q�BU>J�

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Critical Thinking Questions

25. )K QEFP PB@QFLK QEB $�!�2�%� MOLDO>J T>P ABP@OF?BA >P >K FK@OBAF?IV MLMRI>O MOLDO>J FK P@ELLIP>@OLPP QEB 5KFQBA 3Q>QBP ABPMFQB QEB C>@Q QE>Q OBPB>O@E @LKPFPQBKQIV PRDDBPQP QE>Q QEFP MOLDO>J FP I>ODBIVFKBCCB@QFSB��(LT�JFDEQ�LKB�BUMI>FK�QEFP�AFP@OBM>K@V�

26. 4EB P@FBKQFCF@ JBQELA FP LCQBK ABP@OF?BA >P PBIC�@LOOB@QFKD >KA @V@IF@>I� "OFBCIV ABP@OF?B VLRORKABOPQ>KAFKD�LC�QEB�P@FBKQFCF@�JBQELA�TFQE�OBD>OA�QL�QEBPB�@LK@BMQP�

27. )K QEFP PB@QFLK @LKGLFKBA QTFKP +OFPQ> >KA 4>QF>K> TBOB ABP@OF?BA >P ?BFKD MLQBKQF>I M>OQF@FM>KQP FK >@>PB PQRAV� )K TE>Q LQEBO @FO@RJPQ>K@BP TLRIA VLR QEFKH QE>Q QEFP M>OQF@RI>O OBPB>O@E >MMOL>@E TLRIA ?BBPMB@F>IIV�EBIMCRI�>KA�TEV�

28. 0OBPRJ>?IV OB>IFQV QBIBSFPFLK MOLDO>JP >FJ QL MOLSFAB > OB>IFPQF@ MLOQO>V>I LC QEB ?BE>SFLO AFPMI>VBA?V QEB @E>O>@QBOP CB>QROBA FK PR@E MOLDO>JP� 4EFP PB@QFLK MLFKQBA LRQ TEV QEFP FP KLQ OB>IIV QEB @>PB� 7E>Q@E>KDBP @LRIA ?B J>AB FK QEB T>V QE>Q QEBPB MOLDO>JP >OB MOLAR@BA QE>Q TLRIA OBPRIQ FK JLOB ELKBPQMLOQO>V>IP�LC�OB>IFPQF@�?BE>SFLO�

29. 7EF@E LC QEB OBPB>O@E JBQELAP AFP@RPPBA FK QEFP PB@QFLK TLRIA ?B ?BPQ PRFQBA QL OBPB>O@E QEBBCCB@QFSBKBPP�LC�QEB�$�!�2�%��MOLDO>J�FK�MOBSBKQFKD�QEB�RPB�LC�>I@LELI�>KA�LQEBO�AORDP��7EV�

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