L & B Practical 2023
Descriptive Statistics
summary(LandBpracdata2023Nomissing)
ID Gender Age InstructionCond
Min. : 1.0 Male :159 Min. :13.00 Naturalistic:169
1st Qu.: 79.5 Female:151 1st Qu.:21.00 Analytic :142
Median :164.0 NA's : 1 Median :24.00
Mean :163.4 Mean :32.75
3rd Qu.:245.5 3rd Qu.:49.00
Max. :325.0 Max. :76.00
Presses Taskrating Controlrating
Min. : 1.556 Min. : 0.00 Min. : 0.00
1st Qu.: 93.500 1st Qu.: 0.00 1st Qu.: 0.00
Median : 265.000 Median : 20.00 Median : 15.00
Mean : 427.700 Mean : 26.79 Mean : 24.66
3rd Qu.: 541.500 3rd Qu.: 50.00 3rd Qu.: 50.00
Max. :2864.000 Max. :100.00 Max. :100.00
Strategy Drake EverydayIllusions
Yes, strategy:171 Min. :11.00 Min. :17.00
No strategy :139 1st Qu.:21.00 1st Qu.:32.00
NA's : 1 Median :31.00 Median :36.00
Mean :30.93 Mean :35.61
3rd Qu.:39.00 3rd Qu.:40.00
Max. :55.00 Max. :56.00
hist(LandBpracdata2023Nomissing$Age)
describe(LandBpracdata2023Nomissing)
describeBy(LandBpracdata2023Nomissing, group = LandBpracdata2023Nomissing$InstructionCond)
Descriptive statistics by group
group: Naturalistic
------------------------------------------------------
group: Analytic
Hypothesis 1a & 1b:Subjective rating of task: 1: Participants in the naturalistic condition should rate the task as more controllable and that they personally exerted more control compared to the ones in the analytical condition.
t.test(Taskrating ~ InstructionCond, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Taskrating by InstructionCond
t = 2.0639, df = 303.06, p-value = 0.03988
alternative hypothesis: true difference in means between group Naturalistic and group Analytic is not equal to 0
95 percent confidence interval:
0.304916 12.792425
sample estimates:
mean in group Naturalistic mean in group Analytic
29.78107 23.23239
cohensD(Taskrating ~ InstructionCond, LandBpracdata2023Nomissing)
[1] 0.2342429
t.test(Controlrating ~ InstructionCond, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Controlrating by InstructionCond
t = 2.8669, df = 307.18, p-value = 0.004431
alternative hypothesis: true difference in means between group Naturalistic and group Analytic is not equal to 0
95 percent confidence interval:
2.715474 14.599802
sample estimates:
mean in group Naturalistic mean in group Analytic
28.61538 19.95775
cohensD(Controlrating ~ InstructionCond, LandBpracdata2023Nomissing)
[1] 0.3236142
Behavioural effects: Hypothesis 2 Participants who receive the naturalistic instructions should press the buttons more than those who receive the analytical instructions.
t.test(Presses ~ InstructionCond, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Presses by InstructionCond
t = -0.2854, df = 279.04, p-value = 0.7755
alternative hypothesis: true difference in means between group Naturalistic and group Analytic is not equal to 0
95 percent confidence interval:
-125.95195 94.05454
sample estimates:
mean in group Naturalistic mean in group Analytic
420.4175 436.3662
cohensD(Presses ~ InstructionCond, LandBpracdata2023Nomissing)
[1] 0.03293285
Hypotheses 3: Perception of Strategy: People who are allocated to the naturalistic condition will be more likely to report a strategy than those in the analytical condition.
Confusion_Matrix <- table(LandBpracdata2023Nomissing$InstructionCond, LandBpracdata2023Nomissing$Strategy)
prop.table(Confusion_Matrix, margin=2)
Yes, strategy No strategy
Naturalistic 0.6081871 0.4604317
Analytic 0.3918129 0.5395683
chisq.test(Confusion_Matrix,correct=FALSE)
Pearson's Chi-squared test
data: Confusion_Matrix
X-squared = 6.7431, df = 1, p-value = 0.009411
table(LandBpracdata2023Nomissing$InstructionCond, LandBpracdata2023Nomissing$Strategy)
Yes, strategy No strategy
Naturalistic 104 64
Analytic 67 75
Hypotheses 4: The relationship between individual difference and experimental measures: 4a: Scores on the Drake beliefs and the Everyday illusions scales will be positively associated with a greater experimental illusion of control (taskrating and controlrating).
4b: Scores on the Drake beliefs and the Everyday Illusions scale will be positively associated with a greater number of presses.
cor.test(LandBpracdata2023Nomissing$Controlrating, LandBpracdata2023Nomissing$Drake)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Controlrating and LandBpracdata2023Nomissing$Drake
t = 0.82057, df = 309, p-value = 0.4125
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.0649244 0.1570326
sample estimates:
cor
0.04662962
cor.test(LandBpracdata2023Nomissing$Taskrating, LandBpracdata2023Nomissing$Drake)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Taskrating and LandBpracdata2023Nomissing$Drake
t = 0.59589, df = 309, p-value = 0.5517
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.07763032 0.14455216
sample estimates:
cor
0.03387951
cor.test(LandBpracdata2023Nomissing$Presses, LandBpracdata2023Nomissing$Drake)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Presses and LandBpracdata2023Nomissing$Drake
t = 2.2999, df = 309, p-value = 0.02212
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.01878618 0.23752267
sample estimates:
cor
0.1297324
cor.test(LandBpracdata2023Nomissing$Controlrating, LandBpracdata2023Nomissing$EverydayIllusions)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Controlrating and LandBpracdata2023Nomissing$EverydayIllusions
t = 3.9296, df = 309, p-value = 0.000105
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.1096043 0.3215770
sample estimates:
cor
0.2181622
cor.test(LandBpracdata2023Nomissing$Taskrating, LandBpracdata2023Nomissing$EverydayIllusions)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Taskrating and LandBpracdata2023Nomissing$EverydayIllusions
t = 2.5366, df = 309, p-value = 0.01169
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.03211299 0.25006548
sample estimates:
cor
0.1428202
cor.test(LandBpracdata2023Nomissing$Presses, LandBpracdata2023Nomissing$EverydayIllusions)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Presses and LandBpracdata2023Nomissing$EverydayIllusions
t = 3.2795, df = 309, p-value = 0.001159
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.07368587 0.28872825
sample estimates:
cor
0.1834002
Hypotheses 5: Association between experimental measures 5a: The number of button presses will be higher for those who report having found a strategy.
describeBy(LandBpracdata2023Nomissing, group=LandBpracdata2023Nomissing$Strategy)
Descriptive statistics by group
group: Yes, strategy
----------------------------------------------------
group: No strategy
t.test(Presses ~ Strategy, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Presses by Strategy
t = 1.349, df = 282.77, p-value = 0.1784
alternative hypothesis: true difference in means between group Yes, strategy and group No strategy is not equal to 0
95 percent confidence interval:
-34.52567 184.93337
sample estimates:
mean in group Yes, strategy mean in group No strategy
462.1319 386.9281
cohensD(Presses ~ Strategy, LandBpracdata2023Nomissing)
[1] 0.1555362
5b:The two experimental measures of control (Is it controllable AND did the person’s rating of control) should be higher for those who reported finding a strategy.
t.test(Controlrating ~ Strategy, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Controlrating by Strategy
t = 7.7525, df = 303.09, p-value = 1.376e-13
alternative hypothesis: true difference in means between group Yes, strategy and group No strategy is not equal to 0
95 percent confidence interval:
15.92227 26.75517
sample estimates:
mean in group Yes, strategy mean in group No strategy
34.30994 12.97122
cohensD(Controlrating ~ Strategy, data=LandBpracdata2023Nomissing)
[1] 0.8559567
t.test(Taskrating~ Strategy, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Taskrating by Strategy
t = 5.5632, df = 303.93, p-value = 5.814e-08
alternative hypothesis: true difference in means between group Yes, strategy and group No strategy is not equal to 0
95 percent confidence interval:
10.92355 22.88082
sample estimates:
mean in group Yes, strategy mean in group No strategy
34.45614 17.55396
cohensD(Taskrating ~ Strategy, data=LandBpracdata2023Nomissing)
[1] 0.6292935
Hypothesis 6:Measure validity: Scores on the two illusion of control measures (i.e., Drake and Everyday Illusions) will be positively correlated.
cor.test(LandBpracdata2023Nomissing$Drake, LandBpracdata2023Nomissing$EverydayIllusions)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Drake and LandBpracdata2023Nomissing$EverydayIllusions
t = 2.1074, df = 309, p-value = 0.03589
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.00792127 0.22724266
sample estimates:
cor
0.1190337
Exploratory Analysis
Gender differences
Females will score higher in drakes and Everyday illusions than males
t.test(Drake ~ Gender, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Drake by Gender
t = -1.0202, df = 304.99, p-value = 0.3085
alternative hypothesis: true difference in means between group Male and group Female is not equal to 0
95 percent confidence interval:
-3.999860 1.268551
sample estimates:
mean in group Male mean in group Female
30.27673 31.64238
cohensD(Drake ~ Gender, data=LandBpracdata2023Nomissing)
[1] 0.1154691
t.test(EverydayIllusions ~ Gender, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: EverydayIllusions by Gender
t = 0.044391, df = 307.62, p-value = 0.9646
alternative hypothesis: true difference in means between group Male and group Female is not equal to 0
95 percent confidence interval:
-1.339023 1.400833
sample estimates:
mean in group Male mean in group Female
35.66667 35.63576
cohensD(EverydayIllusions ~ Gender, data=LandBpracdata2023Nomissing)
[1] 0.005032788
Females will press more times than males
t.test(Presses ~ Gender, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Presses by Gender
t = 0.072192, df = 307.81, p-value = 0.9425
alternative hypothesis: true difference in means between group Male and group Female is not equal to 0
95 percent confidence interval:
-104.4161 112.3696
sample estimates:
mean in group Male mean in group Female
429.7582 425.7815
cohensD(Presses ~ Gender, data=LandBpracdata2023Nomissing)
[1] 0.008197438
Females will score higher on taskrating than males
t.test(Taskrating~ Gender, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Taskrating by Gender
t = -1.3672, df = 302.72, p-value = 0.1726
alternative hypothesis: true difference in means between group Male and group Female is not equal to 0
95 percent confidence interval:
-10.633130 1.914899
sample estimates:
mean in group Male mean in group Female
24.52830 28.88742
cohensD(Taskrating~ Gender, data=LandBpracdata2023Nomissing)
[1] 0.1556825
Females will score higher on controlrating than males
t.test(Controlrating~ Gender, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Controlrating by Gender
t = -0.77365, df = 307.47, p-value = 0.4397
alternative hypothesis: true difference in means between group Male and group Female is not equal to 0
95 percent confidence interval:
-8.433123 3.673241
sample estimates:
mean in group Male mean in group Female
23.42138 25.80132
cohensD(Controlrating~ Gender, data=LandBpracdata2023Nomissing)
[1] 0.08788667
Gender and strategy
Confusion_Matrix2 <- table(LandBpracdata2023Nomissing$Gender, LandBpracdata2023Nomissing$Strategy)
prop.table(Confusion_Matrix2, margin=2)
Yes, strategy No strategy
Male 0.5294118 0.4964029
Female 0.4705882 0.5035971
chisq.test(Confusion_Matrix2,correct=FALSE)
Pearson's Chi-squared test
data: Confusion_Matrix2
X-squared = 0.33358, df = 1, p-value = 0.5636
table(LandBpracdata2023Nomissing$Gender, LandBpracdata2023Nomissing$Strategy)
Yes, strategy No strategy
Male 90 69
Female 80 70
Age differences-Correlations
cor.test(LandBpracdata2023Nomissing$Controlrating, LandBpracdata2023Nomissing$Age)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Controlrating and LandBpracdata2023Nomissing$Age
t = 0.98837, df = 309, p-value = 0.3237
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.05542545 0.16631684
sample estimates:
cor
0.05613792
cor.test(LandBpracdata2023Nomissing$Taskrating, LandBpracdata2023Nomissing$Age)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Taskrating and LandBpracdata2023Nomissing$Age
t = 0.80154, df = 309, p-value = 0.4234
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.06600095 0.15597786
sample estimates:
cor
0.04555073
cor.test(LandBpracdata2023Nomissing$Presses, LandBpracdata2023Nomissing$Age)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Presses and LandBpracdata2023Nomissing$Age
t = -0.48956, df = 309, p-value = 0.6248
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.13862740 0.08363697
sample estimates:
cor
-0.0278393
cor.test(LandBpracdata2023Nomissing$Drake, LandBpracdata2023Nomissing$Age)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$Drake and LandBpracdata2023Nomissing$Age
t = -1.5133, df = 309, p-value = 0.1312
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.19512471 0.02569373
sample estimates:
cor
-0.08576868
cor.test(LandBpracdata2023Nomissing$EverydayIllusions, LandBpracdata2023Nomissing$Age)
Pearson's product-moment correlation
data: LandBpracdata2023Nomissing$EverydayIllusions and LandBpracdata2023Nomissing$Age
t = -3.0989, df = 309, p-value = 0.002121
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.27943741 -0.06362703
sample estimates:
cor
-0.1736158
t.test(Age~ Strategy, data=LandBpracdata2023Nomissing)
Welch Two Sample t-test
data: Age by Strategy
t = -1.0365, df = 297.86, p-value = 0.3008
alternative hypothesis: true difference in means between group Yes, strategy and group No strategy is not equal to 0
95 percent confidence interval:
-5.397268 1.673258
sample estimates:
mean in group Yes, strategy mean in group No strategy
31.90058 33.76259
cohensD(Age~ Strategy, data=LandBpracdata2023Nomissing)
[1] 0.118081