Publications by Jay Lasker

Correct Models Not Required

01.05.2024

Setup # Packages library(pacman); p_load(lavaan) # Fit Metrics FITM <- c("chisq", "df", "nPar", "cfi", "rmsea", "rmsea.ci.lower", "rmsea.ci.upper", "srmr", "aic", "bic") # A function to compute p-values for different steps of model-fitting stepwise_pvalues <- function(...) { models <- list(...) model_names <- as.character(substitute(list(....

3795 sym R (31280 sym/26 pcs)

The Power to Compare Qst and Fst

30.01.2024

Setup library(pacman); p_load(ggplot2) my_theme <- function(){ theme( legend.background = element_rect(colour = "black", linewidth = 0.5), legend.key.width = unit(0.5, "cm"), legend.key.height = unit(0.4, "cm"), panel.background = element_rect(fill = "white"), plot.background = element_rect(fill = "white"), panel....

957 sym R (5462 sym/5 pcs) 1 img

Wilks' Theorem About Composite Scores

29.01.2024

Setup library(pacman); p_load(MASS, coda, boot, ggplot2, reshape2, dplyr) my_theme <- function(){ theme( legend.background = element_rect(colour = "black", linewidth = 0.5), legend.key.width = unit(0.5, "cm"), legend.key.height = unit(0.4, "cm"), panel.background = element_rect(fill = "white"), plot.background = elemen...

1862 sym R (30862 sym/16 pcs) 2 img

The AC'RE Model: An Application to Mathematics Performance

22.01.2024

Setup # Renaming the SubjectTag columns in CNLSY for merging CNLSY_S1 <- CNLSY %>% rename_with(~paste0(., "_1"), -SubjectTag) CNLSY_S2 <- CNLSY %>% rename_with(~paste0(., "_2"), -SubjectTag) # Merging Links79PairExpanded with CNLSY twice: once for SubjectTag_S1 and once for SubjectTag_S2 merged_df <- Links79PairExpanded %>% left_join(CNLSY_...

433 sym

MGCFA of the Programme for the International Assessment of Adult Competencies Tests in the United States

16.01.2024

Setup library(pacman); p_load(ggplot2, lavaan, PIAAC, kirkegaard, haven) FITM <- c("chisq", "df", "nPar", "cfi", "rmsea", "rmsea.ci.lower", "rmsea.ci.upper", "aic", "bic") usa <- read_sas("PIAACRSAS.sas7bdat") usa <- usa[usa$RACETHN_5CAT %in% 1:4, ] usa$race <- '' usa$race[usa$RACETHN_5CAT == 1] <- 'Hispanic' usa$race[usa$RACETHN_5CAT == ...

2375 sym R (16545 sym/22 pcs)

The AC'RE Model

18.11.2023

Setup FITM <- c("chisq", "df", "nPar", "cfi", "rmsea", "rmsea.ci.lower", "rmsea.ci.upper", "aic", "bic") # Renaming the SubjectTag columns in CNLSY for merging CNLSY_S1 <- CNLSY %>% rename_with(~paste0(., "_1"), -SubjectTag) CNLSY_S2 <- CNLSY %>% rename_with(~paste0(., "_2"), -SubjectTag) # Merging Links79PairExpanded with CNLSY twice: once for...

13717 sym Python (1157625 sym/32 pcs) 1 img

Growth Mindset Interventions and Measurement Invariance

29.10.2023

Setup library(pacman); p_load(lavaan, psych) FITM <- c("chisq", "df", "nPar", "cfi", "rmsea", "rmsea.ci.lower", "rmsea.ci.upper") describe(GrowthMindsetData) describe(Control) describe(Treatment) Rationale Burgoyne et al. (2020) demonstrated that a brief mindset intervention altered the genetic and environmental influences on measured grow...

10205 sym R (33884 sym/65 pcs)

Gaps in LSAT Performance in Canada

18.09.2023

Function MethodOfThresholds <- function(G1, G2, #Category proportions, high to low. epsilon = .00001, #To avoid unfittable values of 0 or 1 deltaS = 0, #Starting value of \Delta for iterations, equal means, see above rhoS = 1, #Starting value of \rho for...

466 sym

Pilot Studies Are Often Unwise

02.09.2023

Setup library(pacman); p_load(metafor, ggplot2, dplyr, tidyverse, scales, rockchalk) CRITR <- function(n, alpha = .05) { df <- n - 2; CRITT <- qt(alpha/2, df, lower.tail = F) CRITR <- sqrt((CRITT^2)/((CRITT^2) + df )) return(CRITR)} my_theme <- function(){ theme( legend.background = element_rect(colour = "black", linewidth = 0....

8781 sym R (21193 sym/19 pcs) 4 img

The Flynn Effect in Spain, 1991-2022

06.08.2023

Setup library(pacman); p_load(lavaan) SDI2.UDI2 = function(p, loading1, loading2, intercept1, intercept2, stdev2, fmean2, fsd2, nodewidth = 0.01, lowerLV = -5, upperLV = 5) { LV = seq(lowerLV,upperLV,nodewidth) DiffExpItem12 = matrix(NA,length(LV),p) pdfLV2 = matrix(NA,length(LV),1) SDI2numerator = matrix(NA,length(LV),p) UDI2...

5664 sym R (69920 sym/22 pcs)